OrigamiBoats Posts Archive Feb 2000 - December 2001 This is a text file of Origami posts, designed for newcomers to Origami and those with limited internet bandwidth. To reduce the size of the file, posts have been trimmed wherever possible, and repeated posts removed. During the editing process, thread links and numbering have been lost. To pursue a specific thread or topic, you are recommended to perform a standard archive search, or examine the original post on the Origamiboats site. Colin Powell Date: Sun Feb 6, 2000 5:24 am Subject: [origamiboats] Welcome to Origami Boats Hi, Welcome to Origami Boats web forum. This is a place for discussion about all aspects of frameless steel sailboats, also known as "folded steel" yachts. Construction, performance, maintenance, cruising anecdotes, rig choices, anything at all... There are many of these fine steel boats sailing around, especially on the west coast of Canada, and it is hoped that this forum will provide an interesting meeting place for owners and potential owner-builders. A "vault" is provided with this forum so that members can upload images and documents for others to view. Please do not send photos and attachments to the list, but rather put them in the vault. From my experience on the Bolger e-group, it keeps everything neat and tidy on the list! Enjoy! your friendly moderator, Alex Christie From: ravencoast@t... Date: Thu Mar 15, 2001 8:15 am Subject: New photos upload to files Dear Origamiboats members, I've uploaded some new files to the group here, of two Swain boats located in Comox harbour. Alex Christie From: cdasilva@i... Date: Sun Apr 8, 2001 10:11 pm Subject: Nice pictures.. I always wondered how you build a boat using origami methods. That, the pictures, certainly looked fascinating. I bet it is very fast to build such a boat. Does anybody knows what are the size limits for such a boat. I imagine as the boat gets bigger the hull thickness increases and therefore it becomes harder to form (bend) the hull. cheers cid From: "Alex & Kim Christie" Date: Mon Apr 9, 2001 4:55 am Subject: Re: steel boats Nice pictures.. Hi Cid, and welcome to the group. I think the biggest boat done in this method was 50' but that was apparently not an easy task. The ideal sizes have been pretty much established with the 31' and 36' designs. With those hulls, the pieces are quite easy to move around before welding. The designer, Brent Swain could probably answer this one best, and perhaps he can speak to the group on this when I get ahold of him to let him know about the group. Stay tuned for more info! Alex From: sunyataspirit@y... Date: Tue Apr 10, 2001 12:37 am Subject: Greetings Swain Fans, It's good to see this group up and running, thanks Alex. I know there are a fair number of Swain boats on the B.C. coast and everyone I've talked to extols their virtue. While I understand it's not possible to give a pat answer, as every boat is finished to a different degree of outfitting and quality of finish, does anyone out there who has finished their own 36 footer have a figure that can be used as a rough indication of cost, in the water, with basic sails and outfitting. There is a beautiful 36 footer in Genoa Bay that has some nice stainless work and ideas on deck, that is well worth a look if anyone is in the area. I intend to 'phone the owner next time I'm up there to pick his brains. Anyone else on the island started building yet? Cheers, Richard From: "Paul Liebenberg" Date: Thu Apr 12, 2001 1:03 am Subject: Re: steel boats yachts boat yacht sailboat sailboats (unknown) Hi Rich, I know of 4 36's curruntly being built on Van Island (quite likely there are more). One in Nanaimo (gene Wunderlin), One in Heriot bay, one in Duncan and my own in Campbell River. Drop by anytime. Paul Liebenberg From: pan@b... Date: Sun Apr 15, 2001 4:31 am Subject: great group I'm very interested in the folded steel concept. I would like to see something for plywood. Anything around yet? Les From: pan@b... Date: Sun Apr 15, 2001 4:38 am Subject: questions How hard is it to clean up the weld areas? Do you have to be a good enough welder that they grind flush to the plate or do you do any filling? How is the metal finished, primers/paint etc.? Is there a website to the designer? Thanks, Les From: "Alex Christie" Date: Mon Apr 16, 2001 7:09 pm Subject: Re: questions Hi Les, I'm hoping that some of the current builders will join in, but I'll take a stab at your questions from my own perspective of someone who has noodled around looking at the boats in build. I am actually trained in wooden boat building, but have been secretly sniffing around at the concept of steel boatbuilding for quite awhile! The welding I have seen on the boats in my area has in most cases only needed grinding flush to the plate. If filling is needed, then not enough metal has been put into the joint in the joint in the first place, and it is time to re-examine the welding technique, rods used, or settings used on the welder. That is, the weld should be "right" to begine with. The slag has to be removed entirely, of course, and if some is left in a pocket it would be a target for rust. Metal finishing: what I remember from Brent telling me was to use steel that is wheel-abraded and primed already. This saves you time and expense from having to sandblast and prime. Then coal-tar epoxy is used (I don't know how many layers), followed by regular enamel. There is a lot more detailed in Brent's handbook on the technique, which unfortunately I don't have on hand as I am posting this from another location while on holidays. Brent can be reached at brentswain38@h... and the book can be ordered from him directly, I believe. The book has a wealth of information and tips for any steel boatbuilding project, even if not using the origami technique for the hull itself. I know of no website for the designer at this stage, though www.boatbuilding.ws shows boats built to his design by a company in BC. There are several other companies or designers using Brent's technique (not always with any recognition of him, I'll add quietly). One is Sailtech in Vancouver, and the other is Designer Patrick Bray, also in Vancouver, I think located at http://www.brayyachtdesign.bc.ca with the "Aisha" 42 footer being the only example. Or put those names in any search engine and they should come up. www.tanton.com also has several designs using the technique, though not much is said about the technique itself on Tanton's website. Hope that is of some help, and if you are lucky, someone else will pipe in here and fill in the (likely many) gaps I have left in my response. Alex From: "Shelley & Foster Price" Date: Tue Apr 17, 2001 11:35 am Subject: Re: steel boats yachts boat yacht sailboat sailboats Re: questions Hello Guys As I recall there was a guy Grahamme Shannon doing some of these boats too, I think he was acting as designer to Sailtech, as mentioned by Alex. See http://www.aviadesign.com/ He did have a twin keel "origami" boat pictured on his site at one time. I also read that he developed a method of computor lofting to suit the "origami" style and claimed that it could be used for many existing designs. Regards - Foster From: sunyataspirit@y... Date: Wed Apr 25, 2001 4:27 pm Subject: Hi all, Just a note that Brent has recently posted some more good advice and interesting facts re. the strength of his boats on the metal boats forum at boatbuilding.com. This is an excellent site which, combined with this origamiboats group should be a terrific resource for all. He also stated that he hopes to be involved with the group soon. Cheers Richard From: "Alex Christie" Date: Thu Apr 26, 2001 4:57 am Subject: Brent Swain to join forum shortly Greetings Origamiboats forum members, I have just been in touch with Brent and he informs me that he will be getting on board Origamiboats shortly. I'll be visiting him on his 31 footer at Comox this week hopefully, and I will attempt to get a few digital pictures to upload of some of the detailing and machinery that Brent has worked out for these boats that will be of interest to all. Brent's solutions to such problems as finding a suitable anchor winch (you just build one) are a breath of fresh air in a cruising world increasingly dominated by expensive factory manufactured toys that more than often do not stand up to the rigors of true offshore voyaging, or even around the bouys. His book provides drawings and notes for the building of just about everything you'd find on a sailboat, from winches to masts, even to propellors, and they work, according to owners I have met. I am also working on composing a photo album of the various Swain boats out there so that members can see how different ones are finished off. Concurrent with this, I hope to convince a few of the owners to give their own written testimonies of the trials (and tribulations) of building their own craft. Stay tuned! Alex Christie From: sunyataspirit@y... Date: Thu Apr 26, 2001 4:17 pm Subject: Brents book Hi Alex, Just wondering if you could get the address to order the book from Brent, price, mailing cost etc. The group seems to be growing nicely and new 'photos will be welcomed. (Any word from Gene yet?, he should be getting started again soon.) Regards, Richard From: brentswain38@h... Date: Fri Apr 27, 2001 9:20 pm Subject: Re: Brents book Richard For a copy of my book "How to Build a Better Steel Boat a Heretic's Guide" 100 pages Paperback illustrated ,please send $20 plus $3 for postage to Suite #427 1434 Island Highway Campbell River BC Canada V9W8C9 Thanks Brent Swain From: brentswain38@h... Date: Fri Apr 27, 2001 9:42 pm Subject: Re: questions Les I usually buy the plate wheelabraded and pre primed with a cold galvanizing primer ( 80 % pus zinc ) Straight from the steel supliers. The extra cost is less than the cost of sandblasting afterwards.This eliminates the need to sandblast . as I use heavier plate than most framed boats, I don't worry about a bit of undercut on the welds. The smoke from the welding does stop paint from sticking and thus has to be washed off with vinegar before you put any epoxy on. My book covers the painting process in greater detail. I don't have a website yet. Brent Swain From: brentswain38@h... Date: Fri Apr 27, 2001 10:01 pm Subject: Re: Nice pictures.. The biggest origami built boat I've seen was a 60 footer built of 1/4 inch p[late by Roy Chambers ,in the eighties . Ken Splett built a couple of 53 footers in 3/8th inch aluminium ,with no problems. As the boat gets bigger , the plate gets thicker, but the distances and thus the leverage you get with a comealong also increases. Theoretically there is no uppersize limit , but the plates for the decks and cabin get large and heavy enough to make heavy equipment like overhead cranes neccessary. I once pulled together a 47 footer , and ended up visiting the physio therapist for several months after . This inspired me to refuse to do anything over 36 feet myself, but others can do the 40 footer if they are masochistic enough. I have pulled together 36 foot hulls in two days from the time the steel arrived , and pulled together hull, deck, cabin,cockpit ,wheelhouse, keel, skeg and rudder in 6 days, without the keel attached. Attaching the keel takes another 4 hours. Brent Swain From: "Alex Christie" Date: Sat Apr 28, 2001 9:35 am Subject: A visit with the designer Dear group, Well, I've had my visit and chat with Brent Swain in Comox today, and enjoyed picking his brain for ideas about his boats. I'll try and relate some of what we talked about, later in the body of this posting. Later on in the afternoon I had a chance to walk out at low tide on the mudflat in Comox harbour and I took some digital photos of the outside of his 31' twin keeler as it sat high and dry. These are now available to see in the files section. The photos Brent showed me of his trip to the South Pacific from which he returned not long ago were inspiring, to say the least! Romantic locations like Samoa, Raratonga and others even more exotic sounding, were the destinations of his voyage. One of the snapshots showed the rare 40 footer, his latest design, and it is very nice looking with an aft cabin and ample pilot house. It happened to be moored to a partly sunken barge at one of the atolls he visited in his journeys. After seeing a photo of this boat, I knew it would be just right as a liveaboard cruiser for my four person family, and now I want to get building such a craft right away! In the back of my mind, I realized what an overwhelming undertaking boat construction can be, having 1 year ago completed a shipwright's course where the building of even small boats was time consuming and a challenge to the mind and spirit. The 40 footer is a VERY big boat compared to the more modest 31 and 36 footers, so I know this project has to be taken on in a serious manner lest it get bogged down by the size and complexity of the process. Bearing this in mind, I chatted with Brent about the challenges of building a boat to his design, and what strategies one could employ for success in building. Having built many boats hulls, and subsequently seen how the owners fare as they detail and complete their vessels, he had some excellent suggestions to make. One is to first get your materials list together and begin to prowl scrapyards, alleys and wherever else you find the various materials that go into the making of a boat. Reading his book, I realized that he has provided drawings for building a sturdy alternative to just about every off-the-shelf marine part you can imagine that goes into a boat. Stainless steel, which finds itself used extensively for detailing, can be found in many places other than expensive marine suppliers. The industrial world has gifted us with a universe of wondrous things made to withstand extremes of use, and many of these things (valves, pipes,galvanized cable for rigging, etc) are available cheaply by weight or by unit. The savings to be gained by finding necessary items at your own liesure and price threshold can be quite high. Money saved early on can be money invested later in other more needy areas of your building project (like a shiny new engine). Brent also suggested that one can build many parts of the boat well before starting the actual hull. Parts like the anchor winch (drawings for which are in the book), the aluminum dinghy, bow rollers, the rudder, aluminum hatches and much more can all be pre- fabricated beforehand, gaining what Brent estimates to be at least a third of the work involved in the overall building scheme. Besides speeding up the overall completion of the boat, it's something to do while searching for a building site, it's possibly fun, and it can be done practically anywhere. Regards, Alex Christie From: burr.halpern@a... Date: Sat Apr 28, 2001 9:16 pm Subject: Interesting Boat Building concept..... I find the idea of carrying over the principles behind Plywood's "Stitch and Glue" or "Instant boat" building concepts to metal, very appealing for one-off boats. At this point this process is clearly in its infancy when applied to yachts, as clearly evidenced by the photo galleries. I would be very interested in seeing these principles applied to hull forms intended to have better sailing performance and more comfortable motions. The hulls shown in the photos certainly appear to be very robust but totally ignore all that is currently known about designing for speed or comfort in a seaway. To some extent, Yves Tanton has been working on developing boats using similar construction techniques but which certainly pay attention to the sailing characteristics of the finished vessel. (See his 'Steel Star' design at http://www.tantonyachts.com/ for a contrast with the boats shown here) I also question the idea of frameless constuction. I think this would tend to produce a much heavier boat than a framed vessel for the same strength, or else a much weaker boat at the same weight. Weight in and of itself does nothing good for a boat. It does not make it strong, or fast, or stable, or safe, or seaworthy, or comfortable. It just makes it heavier, meaning higher stresses on all of the parts and harder to sail in all conditions. Today with the ability to use computer driven cutters, building the internal framework for a steel boat is wildly easier that it had been. Steel yards are able to stack the frames in the computer to minimize waste steel, incorporate slots and tabs to insure proper alignment of parts and produce exceptionally precise cuts at low cost. In my mind the advantage of frame constuction, is a greater guarantee of a precision hull form, greater stiffness and resistance to impact damage, and the ease of building the the rest of the boat. I also wonder about the whole cost issue. This is something that comes up in plywood boats all of the time because it is bacically the same problem. When you think about the cost of building the hull, normally the hull and deck structure represent 10% to 20% of the entire boat building cost. Assuming that you can build the hull quite cheaply using this method, say 75% of the cost of an aluminum hull, or 60% of a well executed cold molded hull or perhaps 50% of a really well executed high tech glass hull, you are only saving maybe 5% to 10% of the cost of constructing the whole boat. (A lot of savings can come from the less than 'gold plater' finishes shown in the photos.) But I would guess that these boats probably have resale vales that are maybe 2/3 to 1/2 of the resale value of a similar sized glass one off with a similar level of finish. While you can easily build one of these hulls in less time than stitch and glue plywood even, I really question whether the econmics are there to support building in steel. All of the above does not touch on the problem that steel boats (especially with steel decks) have with regard to having a high center of gravity, which is very adversely affects ultimate stability and comfort at sea. So while I find this all very interesting I would love to see a discussion of these issues. Respectfully submitted, Jeff From: burr.halpern@a... Date: Sun Apr 29, 2001 6:17 pm Subject: Plywood folded skin boats The basic principles involved in this technique have been applied to plywood quite successfully. In plywood you often hear these techniques referred to as 'stitch and glue', 'tortured plywood' or 'instant boatbuiling'. Today, these techniques are generally applied to comparatively small boats but people like Dudley Dix http://dixdesign.com/ or Yves Tanton http://www.tantonyachts.com/ have produced some considerably larger designs using these techniques or these techniques combined with small amounts of cold molding. Tanton lists 10', 15', 20', 30', 40' "Origami" plywood sailboats. Plywood offers a lot of advantages over steel. It produces a lighter weight boat for a given strength or a stronger boat for a given weight. The lighter weight of the plywood hull and deck sturcture should permit a lower center of gravity which is important for seakeeping, comfort at sea, and sailing performance. If the hull is saturated with either epoxy (or vinylester) and sheathed in a fiberglass or kevlar cloth and saturated with epoxy or vinylester resin, the plywood boat will be more durable and lower maintenance. I suspect that the hull for a plywood boat would take longer to build in that there is more time spent scarfing parts together and building a jig but the jig often ends up as the interior furnishings which may even out the time spent. Plywood construction probably is more expensive than the steel boats shown on this site but if you think about the hull and deck as being 10% to 20% of the overall cost of boat constuction then the difference in cost between the two materials becomes fairly insignificant. One important issue on a plywood boat is take care to avoid delaminations. This requires good quality materials, care in sealing edges and surfaces and care in laminating materials. The good news is that simple delaminations are fairly easy to repair if detected early. Of course there is still the problem with prejudices against wood (or steel for that matter) that supresses resale prices. The real cost of owning a boat is the difference between the purchase price and the resale price. In the US there are real prejudices that force down the values of both types of boat. Some of these are supported by formal institutions. For example I have had problems getting loans for boats that were of plywood construction (except cold molded) and was involved in a deal that fell through because the buyer could not get a loan on steel boat. The plywood boats are actually easier to get loans on but the banks will often require more frequent surveys which of course adds up after a while. Jeff From: "Alex & Kim Christie" Date: Mon Apr 30, 2001 12:50 am Subject: Interesting links Here are some links to designs or boats being built using the origami techniques: Go to this site for a look at a company in the BC interior building Brent Swain hulls. They have some commentary well worth reading: www.boatbuilding.ws Naval architect Patrick Bray of Vancouver has a design using the origami technique, a 42 footer (none have been built to it, since I last spoke to him). He also has an excellent treatise on the use of twin keels. www.brayyachtdesign.bc.ca/aisha Sailtech Yachts uses the origami technique for their aluminum yachts. They started out using Brent's design for their first boats, and have since modified it for a more modern hull in aluminum, but the concept is the same. Not cheap, though likely no different than many custom alum. boatbuilders. The savings in labour by using the origami technique do not appear to be passed on to the owner, in my view, but the boats do look nice. Grahame Shannon (of Amazon 47 fame) did the new design work for them. The Fastwater 47 is basically an origami version of the Amazon. Don't bother asking if he'll sell you a set of plans: I already did and he said no! Too bad, as I believe this would have answered Jeff's concerns regarding a more modern hull form. If we are lucky, more designs using the origami technique will appear that address the need. http://www.sailtechyachts.com Alex From: "Alex & Kim Christie" Date: Mon Apr 30, 2001 5:32 am Subject: Re:Interesting Boat Building concept..... Thanks for your commentary Jeff. I am happy to get some healthy debate going here. I'll try to reply to the points I can, and hopefully Brent will address the questions further when he gets to a terminal at the local library. He does not have a computer or internet connection on his boat, so his responses will always be delayed. Cost of steel boats, resale value: Here on the British Columbia coast, steel boats are held in fairly high regard, most notably for their ability to survive impact with logging debris such as deadheads (waterlogged log which floats vertically with one end just at or sometimes slightly below the surface). The inherent dangers of coastal cruising in BC may in part explain the proliferation of Swain boats in these parts. I have found the resale values on steel boats to be quite high if they are built and finished nicely. With the advances in coating technology, as Tanton says in his description of Steelstar, there is little reason to avoid the use of steel for a boat hull. Use of plywood for hulls: I am trained in wooden boatbuilding myself, a recent graduate of a boatbuilding school on this coast (www.boatschool.com for those interested!). I used to think that plywood might be a way to go for an economically built cruiser, and still don't doubt the ability of the material to function well if properly employed in the right design (Dudley Dix seems to be doing good work in this regard). Sadly, when it comes time to sell, you will face extreme prejudice against your boat just because your ad says, "Plywood hull", even though you've poured heart, soul and much money into it. Phil Bolger has put a lot of thought to this in his books. It is too bad that as a result of this prejudice against plywood, the long term economics for the owner are so much against it, but I guess the dictates of the market are somewhat to blame. Quality: Very subjective when speaking of custom or amateur built boat. I think the ultimate quality of a boat is measured by three factors: good design, good materials, and good workmanship. If you lower your standard on any one of those elements, the end result suffers. That said, I shy away from ever making a sweeping generalisation about any hull material or design, because the world of boats is so highly subjective, and the variables that make a boat "good" are many. For example, I have seen examples of well known designs like the Endurance 35 which I'd gladly go to sea in without a moment's worry. Yet later on I'd see an example of the same type which filled me with horror at the idea of setting foot in it at the dock, because it was so poorly put together. It is not the fault of the design, in this instance, but the mistakes made by the builder which yielded the abomination. I knew of a ferrocement cruising yacht which was built in Holland to Lloyd's specs, and it was a durable thing of unquestionable beauty. Other ferro boats are anything but pretty, but the same can be said of boats of all materials. Some Swain boats are built to gold-plater finish, such as SILAS CROSBY in Comox. It has stainless rigging, roller furling, aluminum mast, and a flawless paint job. Others are more "rough and ready". Each boat represents the individual tastes and priorities of the owner, so the results vary widely. But the main thing is that these boats are being actively used locally and offshore. People are really sailing these things, not just dreaming (like me!). The minimum requirement for a Swain hull or its equivalent is that there is access to a flat surface and a plug-in for an AC welder, and not much else. This means it can be pulled together just about anywhere, because it is so low-tech. It is wonderful to contemplate the use of computer-driven cutters and other technical advances for steel boatbuilding, and I wish such things were more common and accessable. Unfortunately they are not an affordable or accessable reality for the aspiring amateur boatbuilder, so we make do with what we have in order to get on the water to produce a workable product, and again I think this is where Brent's boats come in. As a sociological aside, I have noticed that the typical Swain hull builder tends to be a bit of a "rugged individualist" who avoids expense and complication when economy and simplicity will do the job just as well. My theory is that it's an attitude partly borne of this coast's relatively recent colonial-pioneering past. Early european and asian colonists had to look to themselves to solve problems in an isolated environment, and remnants of this self-reliant attitude remain to be expressed in Swain hull owner-builders today. The origami system is definitely evolving, and could really go far in the future with viarations on the hulls (I'm counting on all of you to keep your eyes peeled for anything that pops in this regard and report back!). Certainly there is no reason in the long term for the hull forms to be limited to a few types, but I think Swain at the moment has effectively filled the demand with a set of vessels which function quite well at minimal cost. Additionally, his book offers simple home-built alternatives to just about every manufactured marine part found in a sailboat except for the engine. This means that lack of a marine chandlery next door is not a barrier to going cruising, though it is a nice luxury if the pocketbook can afford it. I think the current origami boatbuilding technique as used in Brent's boats offers a realistic chance to go from concept ("I wish I had a crusing sailboat") to reality (actually sailing a boat to Samoa) in short order without sacrificing safety or comfort. Any economizing which sacrifices safety and comfort is a dangerous proposition, since the two are inter-related on a long ocean voyage. Speed: The question of the speed of these hulls is difficult to properly address because there are two scenarios to consider: are you measuring a vessel's speed around the bouys in a race, or are you measuring distance made good in a 24 hour period during a bluewater crossing? Brent's Depending one what you want out of a boat, your requirements would be met by two very different crafts. If you want speed AND comfort, you may have to compromise, though I'll add that advances in design are certainly narrowing the gap between racer and cruiser. Weight: Brent can address the issue of weight better than I, but if I recall correctly, the reduction of transverse frames (there is actually a large web of frame-like structures in the midships area in order to take up the stresses imposed by the twin keels) allows the use of thicker (3/16th) plate to be used, vastly increasing its resistance to damage from point-loading. With the weight merely shifting from the frame to the hull plate, I can see no increase in weight over traditionally framed boats. Precision of constructed hull form: I'll quote from Brent's book on this one: "...If the plate for one side of the hull matches perfectly the plate for the other side of the hull, and they all attach to one another at the same relative points with those on the other side of the hull, it's geometrically impossible for the hull to be anything but symmetrical. Any variation in symmetry can only be attributed to variations in the size and shapes, from one side to another, or attachment points of the various parts. For this reason, the symmetry of a boat is dependent on the care the builder takes making sure the parts used for one side are identical to those used for the other side (just like any other method of boatbuilding)." 'Nuff said, Alex Christie From: Date: Mon Apr 30, 2001 5:38 am Subject: New file uploaded to origamiboats Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the origamiboats group. File : /Moonraven/moonraven2a.jpg Uploaded by : ravencoast@t... Description : Moon Raven at Comox 2 From: Date: Mon Apr 30, 2001 8:54 am Subject: New file uploaded to origamiboats Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the origamiboats group. File : /Nuthin Wong.jpg Uploaded by : ravencoast@t... Description : Nuthin Wong Junk-rigged origami boat From: burr.halpern@a... Date: Mon Apr 30, 2001 1:55 pm Subject: Re:Interesting Boat Building concept-response to Alex..... I would like to address a few of your points; Speed around the marks vs 24 hour runs in bluewater, the absense of frames allowing thicker plating and fairness. I often hear bluewater cruisers claim to have really fast days runs in the bluewater environment when compared to more modern designs. This has just not proved to be the case in the various "Atlantic Rallys". In general, heavier traditional boats have had substantially slower passages and have run their engines a significantly greater proportion of the time. In one study of a recent Atlantic rally, boats classified as heavier cruising boats were found to have run their engines more than 100% more than the engine hours of boats categorized as performance distance cruisers. This may be argued to be the results of a lot of factors such as people who buy performance cruisers are more likely to be interested in getting more performance out of their boats and perhaps have a stronger preference for sailing rather than motoring, the lighter boats were at sea for shorter periods of time and therefore even if they ran their engines the same amount each day there were fewer days at sea, and people with heavier boats may be less adverse to running the iron genoa. Surprisingly, the big gains by the 'performance cruisers' occurred during periods marked by heavy weather beating, with other large gains made near the end of the passage in broad reaching and running conditions. On the issue of heavier plating vs frames. It is very hard to make up for the absense of frames with heavier plating. When you engineer the skin of a vessel, the key determinant of plating thickness is the size of the panel. In a typical steel boat under 40 feet, you would expect panels that were less than 1'-6" by 4 foot. If you only have a single ring frame you are looking at panels that are something on the order of 5 or 6 feet in its smallest dimension. In the formulas the span of the panels are squared and cubed respectively. So the larger panel size would need plate, 11 times as strong in bending to have equal strength and 37 times as stiff to have equal stiffness. But 3/16" plate is only 2.25 times stronger in bending than 1/8" plate and only 3.4 times as stiff as the 1/8". The formula for rupture strength also uses span squared and thickness squared. On the other hand, the lack of frames might reduce the posiblity of sheering the panel if the impact was adjacent to a frame. While I have read your repeat of Brent's quote that essentially said all things being equal "it's geometrically impossible for the hull to be anything but symmetrical." That is true in a hypothetical sense but I have seen kit stitch and glue kayaks, where the panels were precision cut and the stitching holes precision drilled go together with some pretty big distortions. With care these distortions can be sorted out and a fair hull produced, but it is one thing to lossen a few wires and push a piece of 1/8" plywood around and entirely another to try to straighten a welded 3/16" steel plate. You might argue these distortions are within an acceptable tolerance and I suppose that comes down to each persons goals for their boat. I am out of time here. Jeff From: sunyataspirit@y... Date: Mon Apr 30, 2001 5:21 pm Subject: Interesting discourse Hi Alex & Jeff, (Thanks for the update on Gene Alex) I've been following with interest the points brought forward by Jeff re. weight, framelessness etc and Alex's response. The thrustand parry of all such discussion is both enlightening and stimulating and it's good to see that this group is off to a great start withrespect to informative interaction amongst members. From the perspective of someone with little technical knowledge of the engineering process involved in sailboat design I hesitate to dip my toes in the rippled waters of naval architecture and insteadwould like to attempt to show why so many people are enamoured with Brent's designs. Those of us who desire to build a sailboat do so because we arenot in a financial position to go out and purchase a finished product. Most builders and dreamers I have met here on the coast are,like myself, pretty ordinary Joe sixpack types, and, as stated by Alex, independent minded. I doubt there are many out there who would turn down the chanceat a gold plater but when all things are considered there are fewdesigns which can compare with Brent's for ease of construction,strength and proven offshore capability. One can bounce claims backand forth over the "frames versus no frames" debate but when WinstonBushnell, a well known local sailor and circumnavigator decides thathis new boat will be yet another Swain design, (his third) and thatthe design has proven itself on a journey through the NorthWestPassage then personally I need no further proof that these are damnfine boats. A comparison of boats from other designers built inmaterials such as wood, fibreglass and aluminum shows that with a w/lof 31' 9" and a displacement of 19500 lbs the Swain 36 is well placedin terms of speed and sea kindliness. With Brents philosophy of simplicity the dream of a cruisingboat is within most peoples reach and I would quote from an articleby Ian Douglas in the May '98 issue of Pacific Yachting in whichBrent's fina From: sunyataspirit@y... Date: Mon Apr 30, 2001 5:42 pm Subject: continuum For some unknown reason my last post became somewhat cramped after posting and the final comments seem to have disappeared. Ah, the mysteries of cyberspace! Brents final comment in the afore mentioned article were, I feel very appropriate. "Insofar as there is more stress, anxiety and worry (displeasure) in sailing a yacht which represents one's life work than there is in cruising in a simple,sound,seaworthy but inexpensive yacht which could be much more easily replaced; a good argument can be made for keeping a vessel as simple and inexpensive as possible" Amen! Lets keep up the interaction of ideas to keep us stimulated, not forgetting however that the ultimate goal is to get out there and cruise! Cheers, Richard From: burr.halpern@a... Date: Mon Apr 30, 2001 6:46 pm Subject: Re: Interesting discourse-reply to Sunyatspirit I too am enjoying this discussion and the courteousness of this group is refreshing and appreciated. I think that a lot of good points have been raised about the nature of the building environment in the Pacific NW. I thought the email that pointed out that these boats were often being built out in the weather in a harsh climate was one that had not really occurred to me but which certainly reflects an advantage that would certainly promote a quick and temperature tolerant building technique. I did want to address one point in sunyatspirit's post. Sunyatspirit indicated in his comments, "A comparison of boats from other designers built in materials such as wood, fibreglass and aluminum shows that with a w/L of 31' 9" and a displacement of 19500 lbs the Swain 36 is well placed in terms of speed and sea kindliness." I really disagree with that a little. Let me put that weight into in perspective. The boat that I am currently buying is an epoxy saturated cold molded hull with epoxy/Eglass sheathing. Sisterships have done multiple circum-navigations and there is one that was built in South Africa, raced in the Indian Ocean, sailed back to South Africa where she was sold. She then sailed up the Atlantic to Scotland. She cruised Europe (North Sea and Med.) and then, depending on which version you believe, sailed from Scotland to the Carribean and back to Scotland and Back to the Carribean. These boats sail out of some pretty harsh environments South Africa, and Bass Straights. While they are not exactly typical of the average distance cruiser, these boats are 38 feet long (33'4 on WL) and weight 10,500 lbs with partial tankage and something like 14,500 lbs fully loaded. In comparison, a length on WL of 31'9" and a displacement of 19500 lbs is outrageously heavy (even if that is a fully loaded weight. While the debate on seakindliness has traditionally been hard on lighter weight boats, the current thinking is that the two main factors controlling comfort at sea is weight distribution and hull shape. (Weight in and of itself has little to do with it) In terms of weight distribution the lower the center of gravity the more comfortable the motion. When you look at more modern designs that have been designed for comfort at sea the center of gravities of the boats tend to be quite far below the center of bouyancy. So in the case of the boat that I am purchasing the center of gravity when fully loaded is 2'7" below the waterline and the center of buoyancy is about 13" below the waterline. (The C of G is slightly lower when the boat is empty.) Just eyeing the 31 footer would suggest that both the C of B and the C of G are quite close the same height. This means a quicker and more rolly motion. The other issue is hull form. Today, we know that the real no-no's in terms of comfort at sea are deep canoe bodies, and hard chines. The deep canoe bodies increase roll angle while the hard chines promote faster roll rates and higher accelerations. In looking at the Swain 36 both of these are exhibited. I understand the strong endoursement implied by the Winston Bushnell example of a sailor circumnavigating successfully sailing the Northwest Passage and then building his third Swain design. That said, I don't think that really provides anything in a more global sense. For example, none of us would buy a Hunter simply because that fellow who previously sailed his Hunter 37 around the world and is now going around in a Hunter 43. I do believe in simplicity. We just suspect that we have different ideas of simplicity. Respectfully Jeff From: sunyataspirit@y... Date: Mon Apr 30, 2001 8:50 pm Subject: continuing the discussion: Hi Jeff, I agree the group seems to be developing as a pleasant forum to discuss various aspects of constructive debate. I don't believe the loaded weight of the 36 footer is outrageously high. Remember we are discussing cruising boats. W. Crealock , with many good designs sailing the world, suggests that in order for a cruising boat to carry all the food, gear, spares etc. necessary for several months of independence then a boat should have a displacement of 8000 to 10000 lbs per person. I agree that a timely passage is important, no-one wants to spend time wallowing at sea, yet frequently boats that are designed for speed, as are the big racers, tend so often to suffer major structural damage when pushed. Yes I know that most are big cats and utilize state of the art, often unproven technology and materials but for the the average person a compromise between speed, comfort and safety is paramount. Good tracking ability as well as pointing well to windward is also important. Both twin keels and a long fin keel are available on the 36 footer and both seem to provide fine results. We all know that much in life is a compromise, from marriage to the house in which we live and it's no different with boats is it? You will no doubt detect a bias on my part for this particular boat and material. There are too many variables in man, boats and the ocean to conclude that one material, design or rig is superior than another and therefore discussions such as this will provide endless hours of entertainment . I'm looking forward to other members chiming in with their point of view, in particular Brent, who's hands-on experience is invaluable. Regards Richard From: "Paul Liebenberg" Date: Tue May 1, 2001 7:13 am Subject: Re: [origamiboats] Re: Interesting discourse-reply to Sunyatspirit The boat that I am currently buying is an epoxy saturated cold molded hull with epoxy/Eglass sheathing. Which boat is this? Betcha I could poke a hole in it with my BS Heretic 36. My Brent Boat is a tough motherfucker, the other day I was inside pounding on the inside with a sledgehammer(wear earmuffs) and broke the fiberglass handle. Different strokes for different folks. Paul, building outside in BC From: burr.halpern@a... Date: Tue May 1, 2001 12:39 pm Subject: Re: Interesting discourse-reply to Sunyatspirit "Betcha I could poke a hole in it with my BS Heretic 36." Lets see here, 19,000lbs and 3/16" steel. If you tee-boned me in the topsides and missed a frame, you are right you would pierce my topsides (62,000 psi rupture resistance and +/-70,000 psi impact). Of course, even at only 10,500, with 5/8" cold molded hull and ash framing, if I tee-boned you in the topsides I could probably poke a hole in you as well(38,000 psi rupture resistance and +/-40,000 psi impact). The difference would be that the framing would constrain my hole from spreading. One purpose of framing on conventional steel (or cold molded) hulls is limit the spread of a tear in the skin. On an unframed steel hull the tear would continue to spread so a tear offshore would continue to work and become larger until you hit a frame or other edge. The good news is that we hopefully will not have to test this theory. 8^) Jeff From: brentswain38@h... Date: Tue May 1, 2001 8:19 pm Subject: Re: Interesting discourse-reply to Sunyatspirit What are the odds of hitting exactly on a frame? When the BC ferry hit the rocks in Gunboat Pass a few years ago it was only creased between the frames . It was holed at each frame .If the frames had been set away from the hull plating it would have been creased the whole way without holing. Frames create a stress raiser, which gives a fixed point against which the plate can tear. Aluminium riverboats now avoid having transverse frames touch the hull at any point as they always used to tear at the frames and nowhere else. As to comparing the strength of steel with wood and fibreglass, pound a steel nail through a piece of wood or fibreglass, then try pounding a wooden nail or fibreglass nail through steel. Beat on a piece of wood or fibreglass with a steel axe , the beat on a piece of steel with a wood or fibreglass axe.This is similar to an impact of a yacht with a container at sea, or a reef. You could never make a hole in a steel hull with a piece of wood (dead vegitation)or fibreglass. Brent Swain From: "Alex & Kim Christie" Date: Tue May 1, 2001 9:26 pm Subject: link to site for Brent Swain book A small website about Brent's boats! http://www.in2net.com/angelo/homepage.htm Alex From: brentswain38@h... Date: Tue May 1, 2001 7:21 pm Subject: Re: Interesting discourse-reply to Sunyatspirit A heavier hull material does a lot to take the snap out of a boat's motion . A light hull with deep ballast makes for a pendulum effect with a short roll, but a snappy one. Twin keels also take the roll out of a boat. They have long been used as roll dampers on all kinds of boats. The keel on a yacht is the fixed point around which a boat rolls . Twin keels give a hull two such fixed points , one dampens the rolling around the other. A wide hull with shallow deadrise tends to follow the surface of a wave giving it a quicker , snappier motion, whereas a narrower , deeper deadrise hull tends to sit steadier in the water and is less affected by the shape of the wave passing under her.When they capsize, wider,shallower hulls have a much greater tendency to stay capsized, and to lose all positive stability at around 120 degrees or less.My boats have positive stability at 175 degrees. As to speed, I recently returned from Hilo to Vancouver Island in my heavily loaded 31 foot twin keeler in 23 days dispite making no easting for the first 1,000 miles .Best run was 150 miles in 24 hours One of my 36 footers left Cabo in a strong NW wind and beat to windward 1006 miles in 6 days. 160 mile days to windward is not uncommon in my 36 footers. I sailed from Vancouver Island to Ensenada in 14 days.I may go slightly faster in a flimsier, lighter boat, but not by any significant amount , not enough to give up much peace of mind for. It may be a bit naive to assume a light displacement boat will stay that way when fully loaded for long distance offshore voyaging. very few do, and they almost always end up weighing far more than their structural scantlings were designed to handle. When at sea I don't worry much about running into floating debris.I've hit enough hard objects at night at sea to be able to say with confidence that I wouldn't be here if I hadn't been in a metal hull. I lost my first boat on Fijian coral reef . If she had been steel, the same grounding would have done no dammage. Brent Swain From: "Alex & Kim Christie" Date: Tue May 1, 2001 9:05 pm Subject: Swain hull analysis Hello All, I think Jeff has brought up some valid points on the issue of heavier displacement vessels versus light displacement. His points are in keeping with a larger ongoing debate in cruising circles everywhere and should provide an excellent touchstone for those who do not find that medium-diplacement Swain hulls fit their ideal. It sounds like Jeff is very happy and confident with his choice of vessel (what is the design name and who is the author of the design, Jeff? I am intrigued), and I am sure it will serve him well. I think it clearly demonstrates that there is lots of room for personal choices to be made in this very subjective arena. Further to this, I do believe there are many light displacement cruisers worth looking at which combine speed, comfort and safety to the best of their ability. This kind of boat is making itself known in the world, but often in forms not available to the man or woman with shallow pockets. Again, Dudley Dix's work might offer something economical to build that really works, I don't completely know. Amor Marine http://members.tripod.com/fredjamor/ has created a 39' 12,000 lb disp. cruiser that has been designed to have positive bouyancy and a liveable interior in the event of holing, It is reported to be able to attain 13 knots under sail. I have been on the boat myself, and was very impressed with it, enough to be tempted to build one! Is the Swain hull considered to be a medium-displacement hull, or is it a heavy displacement hull? Most would associate heavy displacement with the Steel Roberts Spray hulls, whereas the Swain hull would be considered more of a medium-displacement, don't you think? With its fin keel (or keels in the case of the bilge keeler) and skeg mounted rudder, the hull cannot be put in the same category of a Tahiti Ketch, or a Spray, by any stretch of the imagination. I would say that it is a moderate displament hull. At this point, theoretical analysis of the Swain hull is elusive because the only way to do so is by looking at the digital photos (with their parallax errors) or actually seeing one in person. Ideally one should have a set of lines for the average Swain hull to provide more serious analysis of its potential performance compared to other boats, but these boats are not built to lines per se, only patterns (one of the reasons they are fast to build). Of course, being humans, even if we had a set of lines to look at, we could still disagree on how those lines may translate into reality! The best analysis we have now is through the actual experiences of the people that own them, subjective as that may be. It is good enough for many potential builders of this boat type, and many for many others of other boat types. I think we've established the fact that these hulls are not light displacement by any stretch of the imagination, but neither are they extremely heavy. I do believe that for a steel boat, these boats function very well given some of the constraints imposed by the technique with which they are built. Judging by the numbers built, and their continued popularity on this coast, most owners, in return for the gift of undertaking the blue-water life, have willingly accepted any concessions to speed that the building technique imposes. I have not heard of anyone finding that the hulls rolled excessively. It may be telling that even after long cruises, the owners hang onto their boats for a long time. When a boat gives me grief, or appears to present a liability in terms of my continued existence, I get rid of it! On the issue of heavier plating vs frames: There is no area on the hull of Brent's boats that has large areas of unsupported plate, as there are many closely spaced longitudinal members (fore and aft) made of angle iron spaced about 1 foot (owners please correct me the measurements if need), or so apart. These stringers run the full length of the boat in most cases, though it is said to be unneccessary in the extreme ends of the vessel where the tighter conic shape and stressed-skin provides all the stiffness desired. Many owners run the stringers up there anyway, which is their choice. The hulls are self-fairing as they are built, by the way, and easier than you'd think to achieve symmetry. Brent would know more about explaining this than myself, and I'll leave it to him. Perhaps "frameless" is a misnomer for this type, as it gives a false impression that the plate is bare and unsupported on the inside, which it is not. The evenly spaced stringers plus the slightly thicker skin should fulfill equivalent stiffening that transverse frames would, and would not allow a tear in the hull to "work" beyond itself, and I believe this has been proven by hulls which have seen extreme service. Maybe we should start calling them "longitudinally framed steel boats" to avoid confusion! Cheers, Alex Christie ravensoars2001 Sun 2/24/2002 From: sunyataspirit@y... Date: Tue May 1, 2001 4:08 pm Subject: 36' displacement Hi Jeff, The displacement of the 36' I gave in my previous post is incorrect. I believe the correct displacement is in fact 17000 lbs. Richard From: "Alex & Kim Christie" Date: Wed May 2, 2001 7:43 am Subject: frameless boats by Dudley Dix designed to ABS standards Hello all, Browsing the Dudley Dix site, and looking at his Dix 38 radius chine design, http://www.dixdesign.com/dix38pil.htm I was surprised and pleased to find that his boat, like Brent's, also uses a steel stringer system and no transverse framing. Yet the Dix hull fulfills the ABS standards. With similarly spaced stringers and the same plate scantlings, I see no reason why the Swain hull would not also meet the ABS standards. Might I be so bold to assert that, given the acceptance of ABS standards worldwide among those who know yacht and ship design (and insurers as well), and given that a Swain hull could theoretically meet these standards, further debate over whether a Swain hull could be strong enough to go to sea is possibly moot. Far be it for me to squelch debate with talk of mootness, I'd love to know what others think of this assertion of mine! I have italicized Dix's second paragraph for emphasis. On the Dix 38, Dix writes: "Structural design is to the ABS Guide for Building and Classing Offshore Racing Yachts. Construction is of steel using a stringer system and one-off hulls are built over temporary frames. Bulkheads are structural and are bolted to tabs on the stringers. Production hulls can be built over a spaceframe to achieve rapid and economical construction. Excess weight is trimmed out by eliminating unneccesary structure. Most metal boats have transverse framing in addition to bulkheads, resulting in excessive structural weight and wasted structure. With the use of structural bulkheads and semi-bulkheads, the transverse framing has been eliminated." Alex PS Yahoo groups seems to have swallowed some of our posts possibly due to technical errors. If you have found this from your end, please let me know so that I can inform them. From: burr.halpern@a... Date: Wed May 2, 2001 2:02 pm Subject: A question about frameless boats by Dudley Dix Alex: One last question before going out the door. I have not see a structural plan for Mr. Swain's boats. My comments responded to the term "Frameless construction". As was clarified in yesterday's post, these boats are just "athrwartship frameless" as the boats have longitinal framing. In your quote (below) from Dudly Dix, a very sophisticated designer of yacht structures in my book, he mentioned his boats that achieved ABS structral approval. There are two important points here. Dix uses a series of structural bulkheads that are fairly closely spaced (3'4" or so on center on the one design of his that I had seen. These bulkheads are acting as athwartship frames. Does the Swain designs include structural bulkheads? The concern I have here is that it is way easier to build a structural bulkhead to a precisely laid out drawing to precise dimensions and to plank or plate over that bulkhead, than it is to plate a hull and then try to fit bulkheads to it. As you and I know from building boats ourselves, the time savings in building the bulkheads first on a one-off is enormous. The ABS standard in question is required for all racing yachts racing offshore. I think that achieving this standard is pretty easy and none of us would look at the scantlings for the typical offshore racing yacht to be adequate for long range cruising. Respectfully, Jeff From: burr.halpern@a... Date: Wed May 2, 2001 1:31 pm Subject: Comments on this lively discussion... This has been a most lively discussion and I especially appreciate that Mr. Swain took the time to respond. I am not sure how much time I will have before I need to get to the office but I would like to address some of the points and questions that have been raised. I will start with Mr. Swain's, "You could never make a hole in a steel hull with a piece of wood (dead vegetation)or fiberglass." I got a kick out of Mr. Swain's axe cutting wood and or his nail going through wood analogy but I don't think that they have much relevance, nor do I think his statement quoted above is particularly accurate. Analogies work both ways. For example, think of poking a toothpick through a piece of tin foil (do they still make tin foil or is everything aluminum today) or trying to drive a needle into a piece of oak. If you buy into these analogies you would conclude that a wooden boat was stronger. Of course the reality of the situation lies somewhere in between Mr. Swain's analogy and statement above, and my analogy. The skin of a boat fails in a lot of ways but when you talk about puncturing a hull the skin is a pretty thin membrane. (Just ask the crew of the 'Titanic', a notable steel vessel that was sunk by water. OK, it was frozen water.) Lets look at the science here. The formulas for calculating the likelihood of a membrane failing looks at the amount of load present, the strength of the material and the sectional properties of the hull. It's easy to think of steel as being extremely strong as a material. Its properties as a material (assuming high strength steel) per cross sectional area, make it 25% stronger than FRP (depending on laminate and resin) and nearly 10 times stronger than wood (depending on species) as a material. But it is nearly twice the weight of fiberglass and 5 times the weight of wood (depending on species). In calculating the sectional properties, the thickness of the section gets squared. That means that for a given pound of each material, the sectional properties of fiberglass are nearly 4 times the sectional properties of steel and the sectional properties of wood are nearly 25 times those of steel. In reality few wood of glass boats are built as heavy as steel hull boats but then again they don't need to be to achieve equal strength. Next to address another quote from Mr. Swain, "A heavier hull material does a lot to take the snap out of a boat's motion. A light hull with deep ballast makes for a pendulum effect with a short roll, but a snappy one." Again let's discuss the physics here. Mr. Swain's statement represents very dated thinking and the realities of the behavior of a boat at sea. After the Fastnet disaster of the late 1970's a lot of research was performed on seaworthiness and seakeeping. Beyond simple tank full sized vessels have been instrumented and actual roll rates and in recent years accelerations were measured. These studies have continued to today and presented a very different model of the way boats behave in a seaway as compared to earlier models. The actual weight of the boat is a comparatively small component in the equation when compared to weight distribution in a boat. Mr. Swain is right in using the pendulum analysis but he is a bit off on his physics. When looking at the behavior of a vessel in a seaway, the weight distribution is one of two main issues that determines roll rate. If you think of a boat as being a series of pendulums, some rigidly connected and others free to rotate at will, the amount of weight and the distance from the point of pivot establishes the roll rate (the speed at which the boat wants to roll from side to side) and the roll angle. The point of pivot on a boat is not actually a fixed point but a moving point that passes through the center of bouyancy at each angle of heel. If you think of a boat that was a cylinder in shape the point would remain constant but since the center of buoyancy moves as a boat heels the point of rotation moves as well. So, we are really looking at instantaneous center of rotation but that is a fine point in this discussion that will have significance in a later discussion. Thinking of the pendulum example, if you move a given weight further out on the pendulum, The pendulum is said to have a greater moment of inertia. In other words, it takes more energy to start the pendulum swinging through the same angle and the pendulum will swing at a slower rate as weight is moved away from the pivot. The amount of moment of inertia produced in the pendulum is directly proportional to the amount of weight but the distance from the weight to the pivot is squared. In other words a doubling of weight produces a doubling of the moment of inertia but a doubling of the distance from the pivot to the weight means an 4 times greater moment of inertia. Now then, if that weight is carried below the pivot, the larger the angle of rotation the more that gravity tries to pull the weight back toward the center, reducing the energy of the swing (referred to as dampening due to gravity). But if the weight is above the pivot, the further the pendulum swings, the more that gravity tries to cause the pendulum to swing through a wider angle (which in yacht design physics is called 'excitation'). So back to Mr. Swain's quote above, while it is true that increasing the weight of a boat of a boat increases its moment of inertia, slowing its motion, but moving that weight away from the center of buoyancy in the right direction is far more important. Obviously the heavier weight deck and hull produces a boat with a relatively high moment of inertia. This weight (hull and deck) is carried mostly above the center of buoyancy. In fact, in the Swain designs, with their deep center of buoyancy, this weight has a very long lever arm. As a result these boats would tend to have a fairly slow roll rate through a relatively large roll angle. This affect is further exacerbated by the comparatively heavy rigging being advocated. Excitation would be a serious problem in a seaway. This makes for a comparatively uncomfortable motion when compared to a more modern design that has looked at comfort at sea. Mr. Swain's physics is off when he says, "deep ballast makes for a pendulum effect with a short roll, but a snappy one". That is backwards. The large mass of a deep keel located far below the center of buoyancy results in a slower roll rate and with gravity damping a comparatively small roll angle. The large moment of inertia of a modern deep keel boat means a more comfortable motion when compared to pervious generation light weight boats with their higher center of gravity. More on the impact of hull form when I have a moment to continue this discussion later today. To answer Alex's question, Alex asked "What is the design name [of the boat that I am in the process of buying] and who is the author of the design?" I had meant to answer that question in an earlier post. The boat is a Farr 38 design number 72. Although these boats have done well on the race course, design number 72 (Farr has designed a lot of 38 footers and design 72 is the specific 38 foot design) was specifically designed by Bruce Farr in the late 1970's for fast cruising. They were designed for wood or composite construction. These boats have had a very good record of distance cruising in some pretty harsh environments. I don't advocate this as a design for everyone but its ability to perform in a wide range of conditions certainly has appealed to me. Respectfully Jeff From: sunyataspirit@y... Date: Wed May 2, 2001 5:10 pm Subject: Swallowed posts! Hi Alex and members, I find the interaction, information and debate posted by the group to be interesting and helpful. Brents hands-on experiences and knowledge are especially welcome. I have had a couple of posts disappear Alex and I wasn't sure if it was due to an error on my end; apparently I'm not alone. I have a few 'photos of the interior framing/firring of a 36 footer built in Crofton some years ago which may be of interest. I don't have a scanner or the ability to send the images but if you'd like to use them I can mail them to you Alex. Are you still on Gabriola? Regards Richard From: burr.halpern@a... Date: Wed May 2, 2001 6:51 pm Subject: Continuation of this morning's post. The next point that I would like to address is Mr. Swains comment, "Twin keels also take the roll out of a boat. They have long been used as roll dampers on all kinds of boats. The keel on a yacht is the fixed point around which a boat rolls . Twin keels give a hull two such fixed points , one dampens the rolling around the other." Again I would like to discuss the physics of this as well. While it is true that a boat pivots longitudinally around its keel, the keel on a yacht is NOT the fixed point around which a boat rolls. Boats roll around their center of buoyancy. Since the center of buoyancy moves as the heels the point of rotation moves around as well. This is a point of rotation is ideally above the keels. The keel(s) do act to dampen the roll speed and reduce roll angle. Similar to the moment of inertia of a boat due to gravity, the greater the keel area and the further from the instantaneous roll angle that the keel area is located the more roll resistance the keel exerts. So having having a keel that are half as deep but twice the surface area woud be equal to a single deeper keel with half the surface area of a deep keel. That all works with the keel operating in clear water. The problem with using the bilge keels (twin keels) is that one keel is actually operating in the disturbed water downstream of the other as they roll which some what reduces the second keels effectiveness for dampening. So we are talking about an awful amount of surface area to achieve the same dampening as a deeper fin. Surface area (wetted surface) is one of the main sources of drag on a boat and adding the extra surface area required to provide the dampening of a deeper fin certainly further reduces the performance of the boat, especially upwind. While there are wonderful practical reasons for building bilge keel boats, in terms of performance they are a disaster creating huge amounts of drag for less efficient lift. They are at their best when they have minimal surface area and have efficient high aspect ractio configurations. A quick answer to Alex's question "Is the Swain hull considered to be a medium-displacement hull, or is it a heavy displacement hull?" Using 17,000 lbs displacement for the 36 footer, (I don't know where this number comes from if there has not been a set of lines drawings prepared for these boats) the S36 comes in with a length (WL) to Displacement ratio of 247. That would fall in the moderately heavy to heavy category. These classifications are pretty arbitrary and have slowly changed over time but they run something like : Ultralight= Under 120, Very Light 120- 140, Light140-160, Moderately heavy 160 to 240, heavy 240 to 300, and very heavy over 300. Respectfully Jeff From: brentswain38@h... Date: Thu May 3, 2001 10:26 pm Subject: Re: Continuation of this morning's post. - A friend was crossing the Atlantic in a twin keeler, and found the rolling was a fraction what it was on single keelers he'd sailed on. When he got to the Carribean he ended up sailing alongside a sister ship which had a single keel. He said that in the same following sea, the single keeler rolled about twice as far as the twin keeled version of the same hull. My experienc with my current vessel ( seven trips to the Charlottes , one trip to Mexico and back, and one trip to Tonga and back) has been about the same.What's your experience sailing twin keeled boats accross oceans , Jeff? Again, when theory contradicts experience, it's probably theory that's wrong. A boat only rolls around he centre of buoyancy if it has no keels . Suggesting that the large lateral resistance of one or two keels has absolutely no effect on which point a boat rolls around is extremely naive.As it's extremely hard to get a keel to move sideways through the water ,it largely over rules any tendency for a hull to roll around her centre of buoyancy. When a boat heels, the leeward twin keel is dead upright, doubling it's efficiency in terms of lateral resistance.Thus the total area of twin keels needs to only equal the total area of a single keel to give the same lateral resistance. Each twin keel is thus half the area of the single keel .I use the same size piece of plate to build a single keel as for twin keels. Over many successful boats this has worked well. There is thus no need for a single keeled boat to have more wetted surface than a single keeled boat.It certainly has far less than a full length keel. My keels are angled out 25 degrees from the vertical. This minimises the reaction between them as well as making the upright keel twice as effective. I believe that much of the reputation for poor performance in twin keeled boats has been the result of people putting on keels the same size as single keels at right angles to the waterline . Brent Swain From: "Alex & Kim Christie" Date: Thu May 3, 2001 11:20 pm Subject: twin keels Hello all, Patrick Bray Yacht design http://www.brayyachtdesign.bc.ca has an excellent treatise on twin keels well worth looking at. Ted Brewer also wrote an interesting and positive article on twin keels some time back. I'll try and contact him for a copy of this to post to the forum. There is also some designs called "Boojum" which employ twin keels (Chuck Merrell?). I'll dig the URL up for this and post it when I find it. He talks about its roll-dampening effect. Some of the older British twin keeled boats made it to this coast in years gone by, and it seems that many conclusions about them were made based on experiences with these older designs. It would be well worth looking at recent advances in twin keel use in order to get a better picture of how they work. Alex From: "Shelley & Foster Price" Date: Fri May 4, 2001 11:40 am Subject: Twin Keels Con't Hello Guys Some thoughts on this subject from a person who has only sailed long keel boats, and knows didly-squat about most things !! There is little doubt that most twin keel boats roll less, however I doubt that any of the theories proposed here so far actually explain it fully. Rolling can be reduced in most boats through sail trim, and this I think points us to some of the answer, because you can't isolate the action of either the sails or the keels in any boat. The book "The Symetry of Sailing" by Professor Ross Garret explains many of these sorts of interactions. If anyone is interested I will post up the relevant section of the book on controlling roll. Secondly a possible explanation for the reduced speed of twin keels (which is well documented in tank tests) is the vortex drag that is caused by the disturbed water that flows off the keel(s). Again we can see this in the appendages in the air (sails) where a two masted or multiple sail rig is never quite as efficient to windward as a single high aspect sail. Our keels are in effect always "going to windward" or generating lift in terms of their passage through the water. Garrett theorises that this effect could mean that a deep fin keel could dampen roll much more than an old timers long keel (like my boat has - bless her!!) All boats are a compromise and it is about finding the compromise best suited to you situation. This means we can all be right, especially if we honestly try to understand what others have compromised.!! Any takers for these possible explanations Regards - Foster From: "Alex & Kim Christie" Date: Fri May 4, 2001 7:13 pm Subject: Re: [origamiboats] Twin Keels Con't Hello, (Hi Foster) The twin keel question in this context is probably one of those things which is very hard to really get to the bottom of because actual use shows that the concept works well enough that people will accept any minor drawbacks in return for their benefits. In the end, it comes down to a matter of choices made by the builder-owner, of course. I guess it comes down again to the "practical experience" vs "theory" conundrum. For myself, I will choose the twin keel option for two reasons: Reduced draft, and abilty to dry out on a falling tide. In these parts, there are only limited and expensive resources for hauling a boat, so having this option is very nice. Over time, the savings will buy me a SSB radio or some other goodie. Not only that, it opens up anchorages in spectacular places on this coast that most sailors in their right minds would never venture into! My last cruiser was an 18 foot flat-bottomed centreboard boat (a Pelican), and I guess I can't shake the desire to explore creeks! I am willing to sacrifice a modicum of performance for that, while others are not. I suppose in an area of limited tidal range (South Pacific), twin keels may be less important. Fixed, twin keels or "bilge fins" have been added to deep sea fishing boats for roll-dampening action...something in this? Winston Bushnell, who sailed his 26 foot Swain hull through the NW Passage, installed a centreboard. It would likely have been a poor idea to have twin keels on a vessel which could get frozen in ice and be crushed! He was able to skid the boat out of the water on a big sheet of steel (or something like that) for a winter-over in one of the villages up north. I think arctic travel would be the only place where twin keels might occasionally present a liability! Alex From: brentswain38@h... Date: Sat May 5, 2001 11:54 pm Subject: Re: Twin Keels Con't Making the decision of whether to go for one keel or two was one of the toughest decisions I had to make on my current boat , Having sailed her for 17 years since, I would definitly go for twin keels again, but the extra tankage in the single keel would always be tempting. In the eastern South Pacific the tidal range was 2 to three feet , and max 4 feet in Tonga. I could do some hull cleaning in Tonga , but the ability to dry out wasn't much of an advantage. The 4 foot draft was. At Fanning Island I was moored in 4 1/2 feet of water for months. At Christmas Island I barely made it in, bouncing the bottom with 4ft draft. At Aitutaki I found the minimum going in was 5 1/2 ft and hit bottom leaving, too close to the north side of the pass. When you get to Fiji you start to find 5 foot tides , greater in New Caledonia. If vortexes off the keels are a problem, perhaps the wings used on twelve meter boats can minimise the problem. One must be careful to design them so they don't macrame themselves to anchor rodes . The only way to do this is with a model. On the subject of boat building materials, displacement , etc.Most theories assume that cruisers have bottomless pockets and have endless time as they plan to live forever. No discussion of speed is realistic unless you include the time it takes to build, buy, earn the money it takes to build or buy, or otherwise get underway. Thus many of the so called "Fast " high tech boats are some of the slowest on the planet in accomplishing what they are supposedly for, getting one's ass out cruising with a minimal waste of time and effort. For people with limited cash and time left in their life, they are extremely inefficient. The steel for my current 31 foot bilge keeler arrived on april 12th. I launched her on May 12th, a month later.It took me 14 working days to detail her and another ten days to paint her . After a break,it took me ten days to rig her and I was sailing with a roughed in plywood interior for $6,000 Canadian. Someone who did it the "fast ,high tech" way ,and took the necessary time to earn the money to pay for it all, wouldn't sail enough in a lifetime to make up for the time he was suckered into wasting.To catch up he would have to sail at about 30 knots, 24 hours a day for a long time.This still wouldn't add back the extra years you lost to the building and buying process. Besides , who says that life is five times as enjoyable when you are going five times as fast. A friend had his steel delivered about two oclock thursday afternoon and we had a 36 foot hull tacked together by 11PM friday night, with the transom in, bulwark caps on and all longitudinal stringers in. I've tacked together the hull, decks, cabin, wheelhouse, cockpit, rudder, skeg and keel for a 36 footer in 6 days, starting from a pile of steel on the ground,working outside with minimal equipment.The steel cost about $6,000. Try that with epoxy and carbon fibre. If we define the boat as a pleasure boat, then the definition of efficiency would be the maximum output of pleasure for the minimum amount of displeasure (work , expense, worry , lost time which could be spent cruising ) then the more expensive, time consuming and hard to get cruising in a boat becomes, the less efficient she is in accomplishing what she was built for , pleasure. Thus expensive so called "fast, high tech " boats are some of the least efficient on the planet, unless you have endless amounts of cash and time. Spending too much cash and time aquiring a boat also adds to the stress of sailing her .When things get a little hairy, you have your lifes work at stake ,detracting greatly from the pleasure of cruising. Framless steel boats not only represent less of an investment in time and money , they have proven that they will take a lot more punishment than other boats ,and thus have a fraction of the risk of dammage or loss in the first place. Nor are they slow. 160 miles a day to windward in a heavily loaded 36 footer is not slow. 14 days from Vancouver Island to Ensenada in a heavily loaded 31ft twin keeler is not slow. 23 days from Hilo to Vancouver Island , half of it to windward ,in a heavily loaded 31 ft twin keeler is not slow. Brent Swain From: "Alex & Kim Christie" Date: Sun May 6, 2001 11:34 am Subject: Boatbuilding philosophy: the clock is ticking, get on with it! --- a long-winded article by Alex Dear group, Brent has really touched on an excellent point here about being realistic as to what you can accomplish in a given life-span: >....Most theories assume that cruisers have bottomless pockets and have > endless time as if they plan to live forever. I'm feeling philosophical tonight, so forgive me for drifting off on the tangent of mortal nature of boatbuilder/cruisers. My basic premise here is that the boatbuilding/cruising mix should be something on the order of 10/90 (out of 100), not the other way around. But what do we see happening around us? 90/10? Sadly, yes. How can we fight that? I have several Jay Benford books (small ships and cruising designs) which I used to read avidly, dreaming endlessly about my ideal deep sea ship. It was fun at the time, but eventually I got in a bit of a "funk" about these unattainable beauties (sounds like just about every lad's experience in high school, eh?...). Why? Well, here were cruising boats which were way beyond my means at the best of times, and would take the earnings of an entire lifetime, maybe two lifetimes, to attain, with no money left to actually sail the thing! The cruel absurdity of my yearnings for such things eventually caught up with me, and nearly put me off the idea of a cruising boat. Much later in life, I attended boatbuilding school with much fervor, nay-- a vengeance, hoping to circumvent at least one technical barrier to attaining my dreamboats. But I could see that even with training I faced a long building schedule for even the smaller of available cruising designs, due to their complexity. 'Tweren't enough! Ted Brewer (hey, I'm not just name-dropping here, bear with me!), during one of our boatschool field trips to his place last year, showed us recently completed plans for a wonderful little 34' steel cruising cutter he had worked up for a client. I fine, rugged ship of the sea with all the compromises in the right places. It was the best of Brewer and his lifetime of experience in the field, of this I assure you. Though we were learning wooden boatbuilding, we apprentices were moved by the design's "rightness" on paper. One student popped the question, "how much do you think something like that is giong to cost the client to have built?". One of our instructors looked it over, and between Brewer and he, estimated something on the order of $145,000 Canadian. Stunned silence around the room. For that boat, all the labour, new engine, everything ready to go off-shore. Probably a very reasonable estimate in the mainstream boatbuilding market for a custom built yacht like this, turn-key. But I doubt that anyone of us would be sailing over the horizon in it in the near or even distant future, not on our workmen's wages. Ever heard of a rich shipwright? It was very sobering, to say the least. Who hasn't seen the bleak advertisement in their local rag: "53' Steel Ketch hull, engine, decks, etc. Ill-health forces sale." We can write the story behind this one: The unfortunate fellow first got to a stage in his life where he thought he could afford such a project/dream (say, with early retirement), he starts his project with great enthusiasm and money, only to find it taking untold years to complete, his age advancing, his wife leaving (this happens, believe it), and himeself ultimately bogged down, saddled with a great steel behemoth he cannot complete due to his poor health. It is very sad to see, very sad, and I feel for the man's unfortunate lot, while fearing greatly the same trap myself. On a sort of sunnier yet still foreboding note, but still sobering, there is a website I visited which is hot-linked from the Bruce Roberts site, I think it is called, www.homeboatbuilder.com or something like that. I shouldn't have named it (they'll hate me for it), and I mean no ill will, but there is a boat a-building on that site called "Trinity", some 65 or so feet long. It has been an ongoing project since 1988! 12, no 13 years, and not launched. No mention of selling it due to ill-health, and I applaud them for having the stamina to stick with it, so Bravo...But 13 years???? A helluva lot can happen in a decade and bit, don't we all know it? 13 years of not cruising. 13 completely un-recoverable years down the tube. 13 years with a heart attack on top. My wise father, a sailor himself who passed from this world 2 years ago, told me time and again, "Alex, there are two kinds of people in this world: people who build boats, and people who sail them." I tried to prove him wrong, but eventually I saw what he was saying. If you love building in and of itself as a process, then build a replica of Noah's ark, the Battleship Potemkin, or a Navy Destroyer, working on it your whole life, and be happy with it. But if you are more serious about cruising, then you have to do what you can to minimize the building time and maximize your cruising time before the lights go out, plain and simple. Brent's boats are the first kind of design I've seen which not only gets the jump on the building process, but sees it through to the end by offering time and money saving ideas throughout, doing it all more economically than any other system that I have ever examined. It is very hard for any other steel or other material boatbuilding process to compete on a time-cost benefit analysis with Brent's system, yet still yield an end product that will see you safely to hell and back the way his boats have done for many people over a number of decades. I hate to sound so pontifical; what are your thoughts about all this? How do you respond to these 3 AM ravings? ("Get to bed"?!) Alex From: sunyataspirit@y... Date: Mon May 7, 2001 1:27 am Subject: Carpe Diem! Hi Alex, I concur whole heartedly with the sentiments expressed in your 3a.m. musings. I don't know your age but have a sneaking feeling I'm a few years ahead of you on that slippery slope and from what I have learned you seem to have summed up nicely the dilemma facing we dreamers. It is an unfortunate truism that time and age will nibble away at the yearnings of all of those who wish to feel the shudder of their own little ship as she rises to meet an ocean swell unless the act of aquiring that goal is begun as soon as possible. Brents designs and building methods can help anyone with the attainment of a reasonably priced, strong and proven stout cruising vessel, and his philosophy of keeping it simple is so valid, especially in todays material driven society. Far better to have been out there in simplicity than to have hung around wishing and hoping for the latest in gadgetry and hull material. I'm sure we've all read the books that sparked our imaginations, Hitchcock, Purdey, Griffith etc. and there seems to be an underlying attitude amongst all the well known cruisers that it's better to do it in whatever style you can afford than not do it at all. I believe that Brent has brought the dream closer to many of us than otherwise would be so as the number of his designs under construction and sailing the coast will attest. Regards, Richard From: pan@b... Date: Mon May 7, 2001 3:12 am Subject: Origami 1 Sheet Hi all, I have been very interested in the steel origami concept. It is very interesting. I have developed a little boat made from one sheet of plywood. I call the boat the origami pirate ship but in fact it is not folded but simply kerfed and rounded. I guess this doesn't count as origami but it was a fun boat to do with my grandson. You can see the boat at http://www.travelback.com/Origami.htm Have a nice day, Les From: "Alex & Kim Christie" Date: Mon May 7, 2001 4:39 am Subject: Re: [origamiboats] Carpe Diem! Hi Richard, Thank you for your words. At the tender age of 35, I'll admit I am already feeling myself walking the slippery slope of mortality! A patch of grey here, another wrinkle there, more of this and that every day stirs me to get to sea before the Reaper comes for harvest time. If building a Brent boat is the quickest and most economical means to get ocean-bound again, then it is no longer a matter of the heart; it is the execution of pure logic. Further assistance to "getting on with it" was recently provided to me by Brent, who suggested that I get a materials list for my boat, and to start right away scrounging bits and pieces needed for hull construction. If you have such a list, then you are "programmed" with a template in your mind for things like lengths of schedule 40 ss pipe, or sheets of scrap alumimum for hatches and aft bulk-head pilot house door, etc. If it is on your mind, then you'll snap up the real "finds" you'd otherwise pass by. The nifty aspect of steel boat building is that the material is not specialized; the materials could be found anywhere there is a scrap metals yard, or industrial activity creating surplus. Oil field businesses, welding shops, sheetmetal shops, and surely a myriad of other places are excellent sources of steel odd and ends. Alex From: sunyataspirit@y... Date: Mon May 7, 2001 4:39 pm Subject: Pirate ship! Hi Les, You've done a lovely job on that little ship for your grandson. Perhaps you've laid the foundation for a future Swain fan! Regards, Richard From: "Alex Christie" Date: Thu May 10, 2001 6:52 am Subject: Re: Origami 1 Sheet Hi Les, Neat little boat you have put together. For another twist on the theme, have you had a look at the Origami Dinghy in the "Files" section? Made of aluminum, it is one tough little skiff, and has a wheel on the skeg to allow it to be dragged across mudflats or other non-liquid surfaces easily. Regards, Alex Christie (moderator) From: burr.halpern@a... Date: Thu May 10, 2001 3:06 pm Subject: "Life too short to dance with an ugly person" Vs."Go ugly early"-An alternative (This is a very long post so you may want to print it out for convenience) "Life too short to dance with an ugly guy". Vs. "Go ugly early"- An alternative viewpoint. Annapolis, where I live, is a very serious sailing town. There are 20,000 boats registered to one creek in town alone. I joke that no matter how rare a particular design might be sooner or later one will pass through town. Men and woman take their sailing seriously in this place, whether they cruise or race or just plain daysail. Sailing is as much a part of daily chatter as would be traffic in a city or weather to a farmer. Innocent expressions creep into our language from all kinds of sources only to become sailing expressions. (Please excuse the sexist choice of examples but since these examples have crept in the Annapolis sailing vocabulary I figure they are fair game.) A few years back there was a very successful race boat called 'Twisted Sisters' in town raced by a an all woman crew. On their boom was painted "Life's too short to dance with an ugly guy". This expression slipped into local sailing usage to mean, that if you are going to do something don't do it with junk. Its used this way, you are out to buy a new block and you are standing there looking at a Brand 'H' block and a Brand 'X' block. Brand 'X' is 20% less expensive, but you know that Brand 'H' has less friction, actually performs to its safe working loads, and has a lifetime warrantee (no matter what the published warrantee says), so you say to yourself, 'life's to short to sail with an ugly woman." And you grab the Harken and buy it. You do so knowing that when you take that knockdown, and the spinnaker takes a wave, you have a better chance of the block holding than failing. And even if the block is never stressed that hard, you wrap up a day of sailing less tired because you haven't been fighting with a higher friction block. On the flip side, there is the expression, 'Go ugly early." This comes from a bad comedy routine about a guy who'd go to bars to meet woman. He would start early in the evening with the best looking woman in the bar but after an evening or rejection, he'd end up going home late at night with the ugliest woman in the bar. He'd miss the late night news and would wake up completely exhausted the next day. He decided that he was better off walking into the bar and picking the worst looking woman in the bar and "Going Ugly Early." In sailing, 'Go ugly early' is used a lot of ways. In racing, you "might go ugly" early by choosing to tack early across an adverse current early knowing that eventually the current will get worse and cost more VMG to cross. But it is also used to refer to the folks who always try to get by with cobbled together gear. On one hand they are certainly out there before they would be with better equipment but in racing they are rarely in the money and in cruising they always seem to be broken down somewhere putting the old girl back together. Even more to the point, when they go to sell these "cheap boats" they often end up taking a bigger hit than the guy who spent a little more in the first place. As long as I am speaking in hackneyed sayings, I understand Alex's basic point. I am very much a believer in the Welsh (or Scottish) saying, "You are dead for a very long time", which is the Welsh (Scottish) equivalent to seize the day. (Especially since my 50th birthday and as we all know life is 'like a roll of toilet paper, it runs out fastest toward the end' to quote Andy Rooney) But there are a lot of ways to achieve that noble goal. This forum seems to take it for granted that the only way to achieve that goal is to build your own cheap boat, and the only legitimate form of cheap boat is one that has the hull coming together quickly, no matter what other the sailing, construction time, economic or other compromises that are implied. I doubt that I will sway many minds here but I would like to play 'Devil's Advocate' here and point out the options that get glossed over. Why build new? There are a lot of great boats out there at prices well within the price range you are throwing around that would get you out there a lot sooner than building your own and perhaps for less money. Speaking for myself I have been able to do a lot of sailing in my life on a real shoestring. I am not one of those people who advocates, the 'just throw money at it" approach. I can't afford to. I have almost always ''Gone ugly early". From my first boat, a small sloop bought when I was 14 with savings from odd jobs, to my $400 Folkboat that I restored and lived on, to the 1939 Stadel cutter that I bought for $2500, restored in half a dozen months, and which my Dad or I owned for the next 12 years I (I left it with him when I went back to school for my master degree) and so on to my current boat a 4000 lb. kevlar and vinylester 28 footer that works well for my need or the 10,500 lb. 38 footer that I am currently negotiating on, a boat that has previously 'been out there' for years with previous couple who owned her; I have owned boats that can be cruised and single-handed for 32 of the 38 years that I have been sailing and none have cost as much as you folks are thinking of spending on building the boats shown on these pages (the Pirate Dinghy excluded- nice job by the way). I must say that I prefer coastal cruising and that is what I have done the most of my sailing life. I have been blessed with having an occupation that I would probably enjoy doing as a hobby but it does keep my feet nailed down, so that long distance cruising is not in my immediate schedule. But that has never stopped me from sailing and sailing cheaply. I dare say that I know a lot of people who are "out there" who spend less time in a year actually out on the water sailing than I get to sail year in and year out. I have done so by finding examples of venerable designs, in easily 'restorable' shape (Which sometimes comes down to a simple hull wax job, varnishing and painting down below, and cleaning the cushions), and getting out there and going sailing. When I have gone to resell these boas they have held their value and most have sold for more than I had in them. By buying carefully I have done well. My current boat, the worst case of the bunch, is probably going to sell for $3000 less than I have in her after 12 years of sailing the living daylights out her. Let me give you some examples of why I think that if you are in a "Carpe Diem" frame of mind buying a good used boat might make more sense. One of the things I do with my spare time is help people, who are looking to buy a used boat, find the right boat for them. I am not a broker. I don't get paid for this; I am just a guy who likes to be helpful. One guy I helped out bought a Pearson Rhodes 41 for less than 20K. These are boats designed by one of this country's greatest designers at the height of his career. Rhodes 41's are boats that have gone everywhere. They have fallen a bit out of favor because they typically have a gas engine. This boat needed new standing rigging, an engine rebuild, the Aries Windvane needed reconditioning, he wanted a new mainsail, and the interior was a cosmetically mess. In six months the guy refinished the existing interior, recovered the cushions (which were the second set and were not in bad shape), rebuilt the engine, and bought a new mainsail. He had planned to build his own mainsail but actually ended up having a new one built for less by taking advantage of "off season" pricing from a major loft. With all of that, he ended up with a highly regarded 41 foot cruising boat, still had less than $35K in the boat and he certainly had less time and money in her than it would have taken to build a boat of that displacement, no matter how crude or ingenious. Another example was a fellow I exchanged email with, who had bought a Peterson 44 (the cruising boat) that had sunk in her slip (check those so-called 'bronze' seacocks). The prior owner was under insured and so was putting the boat back together by himself when his health and funds failed. This boat was torn apart but the prior owner had bought almost everything needed to put the old girl back together had all neatly tagged and in boxes. My friend chose to buy a short block for the diesel rather than reuse the old one but all of the other parts were there. The interior cleaned up nicely. All told the project was less than a year with the guy holding down a full time job. He left to go cruising with something less than $50K in the boat. When he got back he sold the boat for something over $100K and used the money to buy another project boat, which he now owns free and clear and ended up with a healthier bank account to boot. I have a friend in North Carolina who has a neat 36 foot cruising boat that he picked up for $17K. She did not have an engine or electrical system at all and so was a real 'white elephant'. He bought an outboard, and an array of solar panels and for less than $20K is all set to go cruising. A couple years back a guy stayed with me while he was surveying a boat here on the Chesapeake. The boat was a 41 or so foot steel hulled sloop (Roberts design) that he was buying for just over 20K. She was a mess. The worst problem for prior potential buyers was the bottom plating which had "disappeared one night when the guy was tied up next to a power cruiser with a bad electrical system and the Air Conditioning running." Replacing the bottom plating was made more difficult because that the interior was screwed and glued. (If you build a steel boat, build a removable interior.) But after paying a professional to do the welding, and rebuilding the interior himself a year or so later he had a solid boat. To me if you want to go sailing*now*, then building a boat is not the way to go. BUT if you feel that you must build your own boat, (and I often think that I would get a kick out of that,) then at least build something that has resale value in the market place. Pick a design by a respected designer that has national or international recognition. Pick a design that fits some kind of norm in terms of hull form, rig, and keel types. Pick a design that has charisma. These things do not add as much time and cost as they increase the sailing ability or resale value. Build the boat with decent workmanship and a reasonable level of finish and you might break even when you go to sell. One last point about this "Origami Boat" concept. It appears to produce a hull and deck in a very short time. You quickly have something that 'looks' like a boat. But even on the most time consuming of boat building methods, traditional plank on frame wooden construction, the hull itself is only about 20% to 30% of the construction time. Building a decent interior, rig and appendages, and adding deck and interior hardware, installing the electrical system, plumbing, engine, shaft log, and tanks, and all of the bits and pieces that it takes to make a finished vessel is where the real time to build a boat lies. I question the wisdom of building a building a hull form that is seriously compromised by the construction technique chosen for construction. Before firing off the post saying "what about so-and so who likes his version of the "this or that 35" and sailed her around the world", consider the mass of strange and ill suited boats that are presently circling the globe. Each person can justify their choice and few parents think they have the strangest child in the classroom. To those who are building one of these, I know that I can't change your mind. BUT to those who are sorting out their decision whether to build and what to build, I really suggest that you get out and sail on a lot of different boats. Look at what is out there and understand where current distance cruiser design thinking has taken us. Today, a modern cruising 36 footer typically can tick off a steady 8 knots to windward in breezes over 10 knots, and reach at speeds of 10 to 12 knots. They can sail down into wind ranges below 5 knots and are more comfortable and safer than their forebearers when the sea state gets ugly and the winds have lost their sense of humor. Seize the day, but don't mistake 'rapid incompetence' for 'decisive action'. Do your homework, spend a little extra time to do the job well, and you will enjoy the fruits of your labors for a very long time. Respectfully Jeff From: svbanshee@y... Date: Fri May 11, 2001 6:40 pm Subject: Re: ?"Life too short to dance with an ugly person" Jeff, You hate steel boats; I think we get it by now :) A lot of people I know around here sail these boats. They are really happy with them and won't give them up, despite what anyone else's opinions are, and they've made many successful offshore trips and back. That in itself IS worth something, like it or not. It is a bit like the theory which states that bumblebees cannot fly -- yet bumblebees continue to do so. You can't argue much with success. These boats aren't on the market very often because people hang on to them. When they do sell, they don't go cheap. As for the "ugly" connotation, everything is in the eye of the beholder, isn't it? There is no reason a steel boat cannot be beautiful, and I for one think the Swain boats look great. As for building vs buying, maybe the east coast is crawling with deals to be had, but on the west coast there is just a load of old fibreglass junk from the 70's for the prices he is talking about. When there is little to choose from, building your own boat is a good way out. Last point: I don't think Jeff has sailed out here on the west coast which is infested with deadheads from log booms. If he did, he might think again about steel. You sail at your own risk in a boat which can't survive contact with one of these things at full speed. While I keep an eye out for them, some of them are hiding just below the surface. I don't lose any sleep over it with a steel boat. Tasha From: brentswain38@h... Date: Fri May 11, 2001 7:30 pm Subject: Re: "Life too short to dance with an ugly person" Vs."Go ugly early"-An alternative Many of my clients are building a boat precisely because the have done it in the "bargain" fixer uppers for too long and are tired of dealing with other peoples screwups . The notion that "you only get what you pay for " is a line which has been used to lure in suckers by sleazy used car salesmen and boat salesmen for a long time .It assumes that the quality of anything you buy is always invariably reflected in the pricetag . Perhaps someone should tell consumer advocates like Ralph Nader that they are wasting their time testing products and that all they have to do to determine the quality of what they are buying is to read the price tag. If you want to double the quality of what you are selling , all you have to do is double the price. There is such a thing as a ripoff Jeff. Sorry to blow your illusions .Wanna buy some oceanfront property in Kansas ,Jeff? Jeff uses the term "ugly" in describing an economically built boat, yet some of the light displacement boats he advocates such as the Beneteau "hunchbacks " are to my eye some of the ugliest things afloat, for a pricetag of a quarter of a million dollars plus . Anyone can see from the photos Alex has posted that my origami boats are some of the best looking boats out there, something many people often tell me. Unlike some of the fully framed boats, they are fair enough to be given a high gloss finish without an ounce of filler , and still look as fair as a fibreglass boat out of a mold . While advocating safety concerns, Jeff also advocates light displacement boats which lose all stability at around 120 degrees of heel, then capsize and stay that way.Read "Seaworthyness, the forgotten factor "by Marchage. While an estimated 2500 cargo containers fall off ships every year, the light displacement boats he advocates can't survive a collision with one in rough conditions .With the stuff I've hit at night at sea, I wouldn't be here if I'd been sailing the type of boats he advocates. One of my boats T boned a steel barge at 8 knots with no damage.Try that with the fixer uppers he's mentioned. One often reads of vessels and lives lost at sea which wouldn't have been lost if they'd been in steel hulls. Part of the reason the rusted out Roberts hull he talks about, rusted out , was probably because it was plated with lighter steel to allow for the weight of transverse frames. The other reason was probably because of the amount of disinformation around about steel boats. It's often been said that most steel boats tend to rust from the inside out. It's also been said that there is no need to paint a boat on the inside because the sprayfoam insulation is adequate protection for the steel. DUHHHH. The reason that steel boats tend to rust from the inside out is precisely BECAUSE people don't believe it's neccessary to paint the inside. Give a hull three coats of epoxy tar over wheelabraded and cold galvanizing primed steel and you won't have a problem there in a lifetime. My last boat is 25 years old now and the hull is as good as the day I built her. You can tell where the foam has separated from the steel by dragging your fingernails over the foam and listening for the hollow sound.Where it sounds hollow, dig the foam out and look. If there's no paint under the foam, don't buy the boat. The rather expensive , fully framed steel boats built in BC called the "Foulkes 39" are notoriuos for having unpainted hull interiors and are likewise notorious for rusting from the inside out.Many surveyors will never pass a boat which hasn't been painted inside. This is another reason why people with a lot of experience prefer to build my designs rather than buy a boat. They know exactly how things were done. As for the time it takes , the steel for one of my 36 footers arrived the beginning of february, the boat was launced the 26th of april, the couple moved aboard the may 24th long weekend and went for their first cruise,and they set sail for mexico that fall with a new boat and no worries about how it was put together or what some previous ownner had done. Jeff uses the word "crude" yet when people who have built steel boats using the traditional method of framed boatbuilding see their first origami boat go together , they describe the traditional way as very crude and outdated. Given the amount of complexity and distortion , they also consider the results of traditional methods extremely crude. A friend who built a 40 ft Brewer using traditional methods had to us two 45 gallon drums of fairing compound, much cruder than a fair frameless hull which needs no fairing whatsoever to achieve a much greater degree of fairness. The suggestion that a hull is only %20 of the total applies only to non metal hulls. It takes me roughly 100 hours to pull a shell together , 100 hours of welding, and 100 hours to detail a boat. Detailing includes tanks. engine mounts , cleats, mooring bitts, hatches, handrails, lifelines, pushpit and pulpit, self steering,inside steering, thru hulls ,mast step, etc, etc, the sort of things one has to think about and shop for after buying a fibreglass hull. By the time I've detailed a boat, it's ready for painting and launching. A stainless cleat which could cost $40 for a fibreglass boat can be made of stainless and welded down for under a dollars worth of material, and is far stronger an less prone to ever cause problems. On the subject of resale value , perhaps a quote from my book is in order. RESALE VALUE One often sees people spending large amounts of time and money on teak, stainless, expensive hardware, etc, in the hope of increasing the "resale value". of a boat. Sadly they fail to understand the difference between resale value and resale price. While" resale price" is how much you can get for a boat,"resale value" is the difference between what you can get and what she cost you in the first place. It's very easy to spend an extra 40,000 dollars on a boat in order to increase the resale price by 20,000 dollars , a loss of 20,000 dollars , not counting time spent and lost cruising time.Several of my boats , built on a low budget have been sold for anywhere from two to five times what their owners have spent on them. As the price goes higher, the gap between cost and resale narrows , as does the choice of potential buyers, till spending moe eventually becomes a losing proposition ." One of my 36 footers was built for 17,000 dollars and sold for 65,000 dollars. One of my 31 footers was built for $7,000 and sold for $20,000. Another was built for $15,000 and sold for $30,000. A 29 was built for $4,000 and sold for $23,000. The self steering "airies gear " Jeff mentions sells for around $1500, and I'm told needs at least 6 knots of wind to work. The one I build costs about $15 worth of material and works in 2 knots of wind , and has never had a breakdown. Except for a broken skeg when one of my boats was pounding on a lee shore in huge surf , none of my boats have suffered any serious structural problems, despite several circumnavigations, a single season passage through the northwest passage ( where the only dammage was a set of broken dentures on the skipper when it hit the underwater portion of an iceberg at full speed ). Last winter I sailed from BC to Tonga and back in a single year. Nothing broke except the oilpan on mu isuzu diesel, which I didn't build. Such problem free voyages are almost unheard of on the type of boats Jeffy advocates. Brent Swain From: svjennyp@y... Date: Fri May 11, 2001 8:10 pm Subject: Where can I get a copy of Brent's book? I'd be very interested in reading it. -sara- From: "Alex & Kim Christie" Date: Fri May 11, 2001 8:56 pm Subject: Offshore vs Coastal collisions --different scenarios Brent's points about collisions at sea are a reminder that the possible scenarios and outcomes of collisions during offshore sailing can be very different than those which occur while coastal sailing. While there is always the possiblity of a major collsion causing catastrophic damage in either environment, the offshore sailor is going to have to rely upon him or herself alone to stay alive in an emergency, hence needs a higher level of protection, which has been proven through Brent's experiences. The coastal sailor will not suffer long before rescue, even if his vessel goes down and he is stuck in a liferaft. Building a vessel with a tough a hull to begin with is a proven approach, while building a hull which floats after a holing is another, though there are not many boats like this at present that I know of. Alex (moderator) From: "Alex & Kim Christie" Date: Fri May 11, 2001 9:04 pm Subject: Re: [origamiboats] Where can I get a copy of Brent's book? Sara, Brent's book is available by mail from him directly: To order a copy of Brent's book "How to Build a Better Steel Boat a Heretic's Guide" (illus.,100 pages paperback) send $20 plus $3 for postage to: Suite #427 1434 Island Highway Campbell River BC Canada V9W8C9 Alex (moderator) From: svjennyp@y... Date: Fri May 11, 2001 9:02 pm Subject: Re: Ugly boats To call a Swain boat ugly is to be in complete ignorance of the area of the world in which they were born, and of the people who build and sail them. The true northwest (the West British Columbia coast) is traditionally an environmentally hostile and lonely place, certainly compared to Annapolis. It still is for the most part. Get 100 miles out of the city of Vancouver and you'll find yourself the only human soul around for miles. It is beautiful up here, lush and green and alive but, especially in a boat, you need to know how to take care of yourself for the land is still very wild and unforgiving. One need only to read the stories of local natives to understand the environment. Kumugwe rules the seas here, and will take a boat down at his whim. You'd best be ready. The residents of this area are a fiercely independent and self- sufficient type. You have to be when you live on an island and the nearest grocery store is a day or two away in your skiff. Yet they are the most generous sort I have met anywhere and will help you out in an instant, boat types or land dwellers. I met some of these folks while we traveled from Seattle to Alaska in our boat last summer and my life was touched immensely by their knowledge and kindness. When I see a Swain boat, I see all these aspects of the Northwest in it (my home for 26 years). These boats are certainly not ugly, but demonstrate strength and simplicity -- essential for survival up here. You cannot go down to the local West Marine in most places if your Harken block breaks -- you have to make it yourself or do without. Deadheads and rocks and whirlpools and rapids and williwaws and thunderstorms will chase you down continually. You may have to beach your twin-keeler to fix your prop if the nearest boat yard is 200 miles away. Swain boats are ready for this, built with knowing what must be endured up here, a marvel of engineering, and for that the design is most beautiful. If you've seen this coast and understand what life is like here, you'd think so too. And if a boat can sail this coast (and the Northwest passage no less) they can sail anywhere. No, Swain boats are not meant for sailing around the buoys in Annapolis, but you'd better keep a very keen eye out for Kumugwe if you want to bring one of those plastic boats up here. -sara- From: "Alex Christie" Date: Fri May 11, 2001 9:31 pm Subject: coastal sailing dangerous too Dear Group, After reading Sara's excellent post, I have to revise what I said about coastal sailing! It isn't a walk in the park, at times, although I initially painted it that way. I was thinking of my own area, which is the more benign southern coast near Courtenay. There is very little current, and the waterways are quite open and easily navigated (for the most part). But a little further north, "Up-coast" as it is often called, is a region full of perils equal in ferocity to that which can be found far offshore. Weather, current and isolation are three elements which rule in those parts. You are just as much left to your own devices as in the middle of the Pacific ocean. Alex (moderator) From: sunyataspirit@y... Date: Sat May 12, 2001 12:34 am Subject: Ouch! Well Jeff, As you can see from the previous posts you've touched a nerve. Those of us who don't want to refurbish someone elses boat choose to build from scratch because we want to have the choice of a designer we are familiar with and trust, to utilise material that provides security in an unforgiving environment and to have control over and familiarity with the building process. Although financial considerations are also an incentive,(build as cash flow allows), this by no means should suggest that home finished boats are thrown together crudely. Most people who take on the task are extremely talented to begin with, or develop skills as the project progresses. I know of many boats that have been finished to perfection, one Swain boat I recently came across is indistinguishable from glass and the stainless steel work a joy to behold. Admittedly some people are satisfied with denim, others wouldn't consider anything less than silk. It's all up to the individual. I sailed on an Alberg 37, the one used by Webb Chiles on his circumnavigation and for a factory finished boat it was a piece of junk. Bulkheads coming unattatched, leaks everywhere. At least with a boat one builds from scratch the quality control is in ones own hands. Swain boats are good looking boats. They have a solid seamanlike appearance, not, perhaps, the look of sleek fashion driven racers popular back east but one that inspires confidence, proven in the west coast milieu and offshore. I'm afraid you will find that your suggestions and comments, interesting and insightful though they may be, will find short thrift amongst those adherents, fans and admirers of Swains metal designs. Regards, Richard From: brentswain38@h... Date: Sat May 12, 2001 12:44 am Subject: Re: Offshore vs Coastal collisions --different scenarios Your likelihood of staying afloat after holing depends largely on the size of hole a given impact makes . The tougher the material, and the better engineered the hull, the smaller the hole a given incident will cause. As the stiffness, toughness and resistance to holeing in a steel boat go up by the cube root of the thickness of the material, 3/16th inch plate has 3.4 times the resistance to holing as the more common 1/8th inch plate ,although it's extremely unlikely you will ever hit anything hard enough or sharp enough to punch a hoe in 3/16th inch mild steel, given the small size of the boats we are talking about and the small amounts of inertia we are dealing with .No one has managed yet, despite many full speed collisions with everything from steel barges to icebergs to sharp rocks to coral reefs over the last twenty years . It's not impossible to make a steel boat unsinkable tho the point in doing so seems questionable. One inch foam will float the 1/8th inch deck plate I normally use and 1 1/2 inch foam will float 3/16th inch plate . All you need to do is increase the foam thickness by a percentage equal to the percentage of weight of ballast and other negative buoyancy items in the boat, such as machinery , etc.and give a sufficient overkill. A pound of interior woodwork gives roughly a pound of buoyancy when submerged . 3 inches of foam all around would probably do the trick. A friend had a new aluminium version of the Colvin 35 foot "Saugeen Witch" on the tide grid with the tide out.After working on her they all went to the local pub. When they got back they found that someone had forgot to close off a thru hull, and the boat was full of water and floating off the bottom with about a foot of freeboard.They took pictures of seven of them standing on deck with the boat still floating with a foot of freeboard. Doing this would considerably reduce the interior volume of the boat. From: scottaylor79@y... Date: Sat May 12, 2001 1:15 am Subject: I dig it Growing up around a sailing dingy, to my father's recent tanzer 26 on lac st. louis Mtrl. I love being on the water and looking at the photo's the 44 ft junk - that is my dream boat. I would like to do a lot of sailing up north someday. Brent's designs seem so ideal. I am currently on the east coat, having spent time on the west coast - Jeff I am sorry man but you have no idea what you are mising. Scot From: brentswain38@h... Date: Sat May 12, 2001 1:22 am Subject: Re: "Life too short to dance with an ugly person" Vs."Go ugly early"-An alternative The blocks I use are built by wraping a piece of 3/16th aluminium around a half inch rod, cutting it out in the shape of a single purchase block, rounding it off and puting a sheave machined out of 1/2 inch polypropelene cutting board on a pin made out of a 3/8th inch stainless bolt. The whoe block takes about twenty minutes to make by hand, less with power tools , and costs less than a dollar . No one has yet broken one in the last thirty years despite their being used by several circumnavigators ,and by myself for seven Pacific crossings.To break one you would have to shear a 3/8th inch bolt supported on 1/2 inch centres or tear two layers of 3/16th inch plate .Try it sometime. These blocks greatly exceed the strength of the half inch rope they are commonly used with. By comparison,the yachty , trendy,commercially made blocks are, for the most part, extremely flimsey. When you are building something for yourself, the extra expense of going a little heavier is minimal . For a commercial operation, making millions of blocks, and extra ounce per block adds up to millions of dollars.Thus the term "comercially made " often means made with the absolute minimum amount of material possible. This is the case in many decisions made in the building of a boat. A backyard builder can beef things up and customize the construction of a one off vessel in ways which would be overnight bankrupcy for a commercial builder. For this reason a person buying a boat for offshore cruising is often far better off buying a boat built by an experienced offshore cruiser ,who has his shit together, and was building for his own use , than to buy a stock production boat which was built to sell and the builder's life would never be at stake. Such a boat may not have the same cosmetic "decorative priorities" as a production boat, but few experienced offshore cruisers would be willing to sacrfice safety for "decorative priorities".Most feel , after several years of offshore cruising ,that a good offshore boat is best regarded as a workboat and should be designed and built with the same priorities as a workboat.While cruising the South Pacific, I've met a lot of cruisers who were heading home to trade their "decorative boat" for a workboat. From: "Alex Christie" Date: Sat May 12, 2001 2:50 am Subject: new photo files uploaded to origamiboats Hello group, Thanks to Richard (Sunyataspirit), I have received and scanned a bunch of new photos for the "files" section. They mostly show interior shots of a bare hull, plus two exterior detailing shots. The photos show the position of longitudinal (ie fore and aft)stringers on the inside of the hull, as well as how the wooden furring strips are attached to those stringers. Foam is sprayed into the space between each furring strip to the level of the strips. In turn, bulkheads and interior furniture are attached to the strips. Regards, Alex Christie (moderator) From: yah02840@y... Date: Sat May 12, 2001 3:56 am Subject: Steel,Origami, Twin keeled boats. Where to start ? It all seems to come at once. Now; the Origami method in itself has been around for a long time. The Dutch, always but also the French. The largest builder of Origami boat is the Meta company. They have built hundreds of steel, then Aluminum in a process called " Strongall". Where the aluminum is 2 to 3 times the conventional thicknesses and where it is all skin with very little reinforcing in ways of folding the metal. They are yachts, and not cheap but still reasonable. The largest is about 58'. The company covers sail and power boats. Twin keeled boats are being pursued actively by another company, also in France. Having built over 200 "Romanee's" (37',the first aluminum boat built in series, and dozens more of one offs aluminum vessels. Right now they are convinced of the advantage for cruising boats to adopt twin keels. The models are 54', 47', 44' and 37'. All under construction. All in aluminum. I applaud to the ideas presented with this board. From: "Alex & Kim Christie" Date: Sat May 12, 2001 7:51 pm Subject: Boatbuilders in france using frameless techniques Thanks to a tip from one of our members (merci "yah02840"), I have dug up the website of Meta, who builds yachts of aluminum. They use no frames and very thick aluminum plate. Not exactly the same as Brent's technique, but close. They have yielded some very nice results. http://www.reducostall.com/index.htm See attached photo of "Armelle" a twin keeled 17.5 metre boat on a mudflat. Alex (moderator) From: "Alex & Kim Christie" Date: Sun May 13, 2001 5:31 pm Subject: website link to Dove II Via Richard, here is a link to a website which has a page on one of Brent's boats, Dove II, owned by author Gordon Harris. http://www.geocities.com/TheTropics/Cabana/1237/boat.html Alex (moderator) From: brentswain38@h... Date: Mon May 14, 2001 9:54 pm Subject: Re: website link to Dove II The Homewood Road address given in this website is no longer valid as that place was sold years ago. My new address is Suite#427 1434 Island Highway , Campbell River, BC V9W8C9 Canada. Anyone wanting to compare voyaging in "Low cost Industrially rigged yachts " with cruising in expensively rigged "high tech" yachts would be well advised to read Bernard Moitessiers two books "The Long Way" and "Cape Horn, The Logical Route" In The Long Way , Bernard sails 1 1/2 times around the world non-stop through the roaring 40s and around the horn with no gear failures whatsoever, except for bending his bowsprit when he hit a freighter with it . Few stock boats can sail accross the Pacific in the benign trade wind areas with commercially made "High Tech Yachtie " hardware, without occaisional gear failures . Brent Swain From: burr.halpern@a... Date: Sun May 13, 2001 4:54 am Subject: Re: Boatbuilders in france using frameless techniques This is much closer to what I have been suggesting in some of my earlier posts. The Armelle approaches my idea of proper yacht design design thinking. Fairly shallow canoe body, fairly straight and very fair buttocks, fine bow and more powerful stern sections. Even the use of bilge keels follows the current thinking on the proper design of bilge keels which says, if you are going to do bilge keels they should be as high aspect ratio as you can make them and set-up to be vertical at about 15 degrees of heel which is also the case on the Armelle(More than 15 degrees of outward angle and they are less effect at ideal heel angles in the range of 10-15 degrees and they form a tripper when hove to across breaking waves). They have used bulbs on each keel to lower the center of gravity which should give them a very high angle of positive stability. It is hard to tell from the picture but the one shortcoming of the Armelle in my book is that the bow seems to have a flat on the bottom rather than being Vee'd for the first third or so of the boat. A bottom flat really pounds in a chop and can be pretty noisy when you are trying to get some sleep. Jeff From: "burr.halpern" Date: Sat May 12, 2001 1:13 am Subject: Re Ugly Hey Alex, As moderator, please do me a favor and point out that nowhere in my long post did I call Brent's design's ugly. I used two metaphors intended to reflect two very different points of view. The fact that both contained the word "Ugly" and derived from the less gender senitive side of our sport was probably a faux paux on my part. In any event, I do not want to get into a running gun battle with Brent. It is clear to me that if I post engineering data showing that 3/16" steel is not as strong in an impact as 1/2" glass it will be dismissed out of hand. Or if I start citing current data rather than a Marchaj's 20 year old data about designs that were already obsolete twenty years ago, it will be dismissed as "bumble bee's in flight logic". (Which may be the perfect analogy since it too is a very dated example. That analogy about the buble bee not being able to theoretically fly dates back to the very early modeling of aerodynamics in the 1940's. Using current technology we are precisely able to model how a bumble bee flies.) To wildly throw out that modern boats have a ultimate stabilty of 120 degrees is just plain bullshit. That has not been the case in the last 10 years with most modern boats achieving 135 degrees or more positive stability with many IMS based race boats achieving 160 degrees and up. I also wonder why Brent thinks he has a positive stability above 120 degrees. In EU testing of actual steel hulled and decked small vessels they were generally found to have very small righting angles because of their high centers of gravity. They look good on surrogate righting moment approximation but according to the STIX (Stability index calculation) studies in actual righting moment situations did very poorly. In any event, there is no more use to me trying to explain all of that on the Origami Boats board than it would to try to explain carbon dating to a fundimentalist Christain. I did not want to imply that I thought Brent's boats were ugly, ( I think aethetics are in the mind of the beholder) and I don't wish to leave the impression that I had. While I don't particularly like Brent's voodoo approach to the science of naval architecture, I don't think that I should get in a running gun battle with him either so please be so kind as to point out that I never said they were ugly. I'll see you at 'light cruisers', a world much closer to my own. Thanks jeff From: "Alex & Kim Christie" Date: Mon May 14, 2001 10:53 pm Subject: fairness of frameless hulls as seen in photo Dear group, Here is a shot of the underbody of Brian Gilroyd's twin keeler. Note how smooth the freshly painted hull looks, especially near the stern where the gloss should show any unfairness. Apparently no time is expended fairing these hulls with filler because the frameless steel hull skin does not create the same humps and hollows that regular framed boat get from welding distortion. Alex Christie (moderator) From: John.Olson@t... Date: Tue May 15, 2001 12:07 am Subject: Stability, was: Re Ugly I have no problem beleiving that Brent's 31 footer has positive stability up to 120 degrees. I've had Eclectus near that once, in a storm north of Bermuda, and it popped back upright faster than you you would think possible. The radar reflector on the top of the mast was damaged when it hit the water, and the trajectory of the cabbage that flew out of the galley and smashed against the cabin side opposite suggests the boat rolled to over 110 degrees. Stability index calculations are sketchy rules-of-thumb at best, and don't come close to predicting how a vessel will react when it's in conditions where all that righting moment is used in anger. Cheers John From: "Alex & Kim Christie" Date: Tue May 15, 2001 1:51 am Subject: Carl's boat, other pix uploaded Dear group, Here is a nice romantic shot of a 36 footer owned by Carl, at anchor in Comox. A very good example of the type set up for full time liveaboard life, it's current use. Also, an interior shot of Brian Gilroyd's 36 footer, showing a high level of finish. Yesterday I took a field trip into Courtenay and got some shots of a 36 footer in-build at the home of the Austin family. All photos are in the files section in the "Austin Hull" photo album. Some excellent details shots showing how attached parts (cleat, handrails, bollard) are welded in place, and therefore unified with the hull in a most inseperable way. In English, "good luck tearing them off, even if you tried!". It is of great benefit to steel boatbuilders that stainless steel can be welded to mild steel, as this avoids the need to bed and bolt down all fittings. Cheers, Alex (moderator) From: burr.halpern@a... Date: Tue May 15, 2001 12:42 pm Subject: Angle of heel I congratulate you on surviving a knock down of nearly 120 degrees of heel. To put that in perspective, -At 45 degrees surfaces that are normally vertical become easier to walk on than normally horizontal surfaces. -at 90 degrees, most boats dip their spreaders in the water and the deck is vertical so it is very difficult for someone on deck to stay aboard, primarily hanging vertical and using normally vertical surfaces like ladders to get a foot hold. Almost any loose item on board will fall to leeward, including unrestrained batteries. -Typically by 95 to 100 degrees, most boats have the tip of their mast in the water. Vertical surfaces are now pointing downward and so crew on deck typically are hanging from what ever they can grab. Winch handles in normally vertical open pockets will slide overboard. -Typically by 100-105 degrees the mast is in the water up to the spreaders. At this point most boats are past the point of maximimum positive displacement. (In other words the amount of force trying to right the boat has begun to decrease) They are sliding to leeward on their topsides and their mast and sails to leeward are generating some "lift' downward trying to overturn the vessel. This dynamic lift can be emormous and is what generally damages rigs in a rollover. The weight of seawater on the sails begin to dampen the speed at which a boat will come up and can infact actually work to pull the boat over. -By 120 to 130 degrees the base of the mast on most boats are in the water. Dorades and the like are in the water. -By 135 degrees objects that were previously right side up are now upside down and anything which is not held down and has not slid will fall across the cabin. It becomes easier to stand on the cabin top than to stand on the side of normally vertical surfaces. At this point most boats that do not have a keel equal in depth to half its beam (which is why most surrogate positive stability calculations look so heavily at draft and beam) has pretty much lost positive stability as the weight of the keel is now inboard of the boat's center of buoyancy. Heavy decks and rigs become the ballast that tries to pull the boat over toward inversion and it takes a wave of other destabilizing force to rock the boat sufficiently to bring the boat back up. When we read published ranges of positive stability, these are generally based on surrogate formulas that are not terribly accurate because they do not include a component for center of gravity and generally do include a calculation for the buoyancy of the cabin structure. Even when we see full blown positive stability calculations they generally reflect static calculations and as I mentioned above the dynamic overturning moments of a boat sliding on her topsides with the mast in the water are tremendous. Modern offshore raceboats are required to have a calculated 135 degrees of positive stability calculated statically. From Issabelle Autissier's overturning in the Southern Ocean, we all know that in the real world that is not enough to predict that the boat will in fact come back up. Jeff From: "Alex Christie" Date: Wed May 16, 2001 11:00 pm Subject: Invitation for daysail on 36 footer An invitation: Anyone with an interest in trying a daysail on one of the 36 footers in June or July, please reply to me and I'll let you know when a date has been arranged. If there is sufficient interest, I'll approach some of the owners locally to put together an outing. The most likely location would be Comox harbour, British Columbia, Canada. Alex (moderator) ps ongoing technical probs at Yahoo seem to have delayed a few messages, swallowed posts, and/or affected delivery settings. Check your settings and make sure they are what you had before, and that all your messages are getting through! From: willyacht@y... Date: Thu May 17, 2001 11:39 am Subject: Swain 40 ft? Anybody building one? What are the prices for Brent Swains plans? I read some discussion on positive static stability anybody have figures for the 36 Footer and 40 footer? The pilot house version will probably be self righting? Will From: willyacht@y... Date: Thu May 17, 2001 12:01 pm Subject: ABS? I read with some interest the posts on ABS construction standards, ABS is an obsolete standard for pleasure sailing vessels. Even in the hey day of ABS there were some noted structural failures even in Steel and Aluminium vessels. Numerous cases were documented by Prof Joubert in the Small Ships Journal. Why designers are currently still designing to an obsolete standard that is not supported is beyond me. If you think a designer has credibility by using ABS you should think again. The best standard today is German Lloyds or Veritas, but i cant ever recall a plan peddler designing to these standards. So in my opinion knocking Brent Swain on so called standards when most boats are being designed and built to something that is not current is not fair. You could say all current designs are based on guestimates rather than accepted structural engineering standards. Seondly no frameless boat would have ever got ABS plan approval since they simply never met the scantling rule fullstop. Most of Dudley Dixs frameless work is based on and is similar to what Van Der Stadt are doing. Van Der Stadts hulls are not Frameless and they will even confirm this. None of the Van Der Stadt Frameless hulls meet German Lloyds standards and none of them will ever, since German Lloyds only classifies yachts above 14 metres, and most of their new designs are designed to Lloyds. Comparing Swains hulls to Van Der Stadts, i would say the Swain Hull is a better designed structure since Van Der Stadt scantling system is haphazard at best and large areas of the hull in crucial areas have no major framing or anything that represents structural support, i suppose in many ways they are frameless. Structurally good or bad? only finite element analysis will reveal if building hulls this way is a science or hocus pocus. Will From: willyacht@y... Date: Thu May 17, 2001 12:11 pm Subject: Re: Boatbuilders in france using frameless techniques The French have an unhealthy appetite for super wide beam boats with poor static postive stability. What is even amzing is that i met a Frenchman in Sydney ho just returned from the South Pole in a Meta boat with a 101 degrees positive, he was convinced that that figure was okay. I must admitt i like the look and practicality of the many French Chine and Frameless boats, they have shallow draft and many other virtues, but stability is not one of them. Not that this cant be corrected. Besides what boat is not noisy in a chop and who can really sleep in the bows anyway when thing get lumpy. Will brentswain38@h... Thu 5/17/2001 From: willyacht@y... Date: Thu May 17, 2001 12:32 pm Subject: Re: Re Ugly Beauty is in the eye of the beholder. I would say you must be talking about boats in the last year or two. Most modern boats that were sold as cruising boats had numbers well below 120 degrees. Just look at the Jeaneaus, Beneteaus and many other assorted odds and sodds. Just pick up any book on boat design or refer to any back issues of any Cruising Magazine or even Sea Horse you will remember that 125 degrees was considered conservative and 120 degrees was okay. It was only the Pacific Creaklock and Island Packets that pushed the stability envelope. Certainly Bruce Farr was no believer in high static stability, and most in the race world believed that it hampered speed. IMS has only tranformed itself in the last 1.5 years, the average IMS boat was hovering around 110 degrees. Most designers were using 120 degrees as the target figure for offshore use. Anyway its just amazing to see how authors and "experts" have all suddenly become true believers in high static stability numbers. There is no doubt that smaller steel vessels have poor angles of vanishing stability, that we can agree on. But generally if the beam is about 1 ft less than the same size high stability plastic boats these steel vessels come out okay. Its only the recent crop of designers that have simply designed for fibreglass and transferred the design to steel that have done badly Van Der Stadt is an example of this. Many of Dudley Dixs small steel boats have stability numbers over 130 degrees even in his small Hout Bay Design. His Ankon 38 is well over 140. Roberts early steel designs with the narrow beam had excellent numbers his new designs which pursued beam are not that great. As a rough rule of thumb 1 foot less in beam for the same size as fibreglass makes steel boats okay. STIXS and STOPS is obsolete and more current models barring the current CE standards are much better at getting the correct numbers. There is no excuse for any mainstraim designers not having a full stability suite of software, that is the only way to accurately come up with a figure, besides they could come up with a number for every possible loading. Will From: pvanderw@o... Date: Thu May 17, 2001 3:06 pm Subject: Re: Ugly > Certainly Bruce Farr was no believer in high static stability, and most in the race world believed that it hampered speed. I agree with the tenor of your remarks, and your comments reveal a deeper knowledge than my own, but I want to make a comment on the above. A racing yacht designer is at the mercy of the creator of the rating rule. He must work to design the most seaworthy boat possible within the envelope of potentially winning designs. If it is not possible to meet some criterion of seaworthiness (e.g. some stability standard) then either seaworthiness is compromised or the designer seeks some other line of work. This was all made completely clear by the Fastnet disaster. As to engineering, I think it only fair to consider that a design office like Farr's which has worked on many high-profile, highly funded programs has developed some proprietary information about structure. Or, to use an older example, if Rod Stephens said a boat was good to go, that would mean more than nominal compliance with a bureaucratic standard. I am suspicious of bureaucratic standards in any event. There was an excellent article by Kurt Hughes in Multihulls magazine some years ago about the development of a multihull standard. You don't have to agree with Hughes' notions of what the standards should be in order to agree that the system that sets the standard is unrealistic about yachts. Peter From: burr.halpern@a... Date: Thu May 17, 2001 1:52 pm Subject: Will's posts really hit at the core of these issues... I think that the series of posts by Will- 'Willyacht' really hit on a lot of key points. Boiling them down, older structural design guidelines typically were 'scantling rules'. These attempted to use empirical formulas to develop structural component sizes based on 'standard framing and skinning models'. These worked fine and were pretty conservative when used as they were intended. In principle, designers could enter the characteristics of a design that was similar in character to an assumed 'type' and end up with appropriate frame and skin scantling. These models did not attempt to do any stress mapping but basically attempted to design for assumed 'worst case' loadings based on what worked in the past. This is what we used when we were designing steel hulled vessels in the early 1980's. The failure of these scantling rules is that they really did not provide design data for alternative construction techniques, such as the 'frameless construction' techniques being discussed on this forum. In the past when designers wanted to design something 'out of the ordinary' they would rely on simple static calculations which used empirical loading coefficients that assumed reasonable safety factors. These empirical loading coefficients were pretty good for normal conditions but many designers would augment these loadings in areas where they were percieved higher loading or risk. (For example a designer friend of mine would calculate the load necessary to stop a boat dead in tracks at full speed and spread that load over a 4 square inch area. That load would be used for the static calculation of the forward third of the boat below the heeled water line of the boat, and would design fin keels around twice the load of a dead stop at max speed.)As Will mentions, Deutche Veritas produces one of the more conservative and ballanced set of coefficients. These empirical design practices were really all that could be done because accurate stress mapping and the tools to use this stress mapping data was so far beyond the financial ability of a normal designer. Even today the most accurate of stress mapping tools, 'finite element analysis' is only available to the most well funded projects. That said, and as Will's post was suggesting, there are some pretty reasonably priced and readily accessible simplified yacht structure programs that produce reasonable localized loadings. Using these loadings, a designer using reasonable judgement can size skins and framing that should work quite well. It is a similar situation with stability calculations. In the past, very simplified calculation systems tried to develop 'rate' stability of boats using 'surrogate' calculations. In other words these surrogate calculations did not attempt to actually calculate the actual stability of the boats, which was very difficult using hand calculations or even early computer programs, but would look at factors affecting stability and take a simplified rough guess at how a boat might perform in extremis. Today there are some very good software packages which actually come much closer to predicting static stability curves. These stability prediction programs have really turned our previous our earlier rough stability curves on their ears. Heavy cruising boats have been found to not do as well as we all would have assumed and that lighter boats with deeper centers of gravity have done much better than expected. Coming back to the issue of real world designing a 'safe sailing vessel', today, designers use a wide range of methods to make these two critical design evaluations, from simple seat of the pants 'I did this before and it hasn't broken yet' to finite element analysis of major projects. Each designer must decide what works for their own practice. I would be very interested in the hearing about the techniques that Brent employs to calculate the stability curves and structural scantlings for his designs. Lastly, I never said that I thought Brent's boats were ugly! Respectfully Jeff From: brentswain38@h... Date: Thu May 17, 2001 9:28 pm Subject: Re: Boatbuilders in france using frameless techniques To balance well and have a lot of directional stability, a boat should have the same longitudinal centre of buoyancy when heeled 30 degrees as upright . If she squats slightly in the stern it's OK, but if the bow sinks and the stern rises as she heels, she will have very little directional stability. Thus very lean bows and wide "powerful" stern quarters will make a boat cantankerous on the helm in a following sea. My last boat had that problem . For my current boat, I narrowed the stern by about three inces on each side , and added 3 inches to the foreward waterline beam on each side. I then extended the transom about three feet aft and sqaued her stern down. The difference was amazing . The new boat can be gotten to self steer with 15 knots of wind on the quarter with the helm free and no self steering, something the old boat would never do. Even motoring I can leave the helm for long periods of time. With so much extra directional stability, she loses a lot more speed when I tack.This would be a curse for round the bouys racing boats, which is why they are designed with such wide sterns and narrow bows, to eliminate much of that directional stability.For offshore , shorthanded cruising, however, priorities are the exact opposite.Directional stability improves speed when you are being steered by a windvane in a straight line. You don't have to shorten sail and reef to keep her going straight. Twin keels with an angle of only 15 degrees off the vertical are more efficient when you are only heeled 15 degrees, but at greater angles of heel , when you really need it they are far less efficient. The greater the angle off the vertical, the less the intereaction between them . Higher aspect means higher leverage on the keel with a smaller, narrower base to support them. The structural strength of higher aspect keels would be less for a given amount of material. As " if you haven't been aground , you haven't been around" applies to all cruising boats, structural strength may become critical. Bulbs do lower the center of gravity, but can be extremely labour intensive. Perhaps the use of retired oxygen bottles may be an option with a little cutting and modification. Does anyone know what kind of steel thay are made of ? Brent Swain From: brentswain38@h... Date: Thu May 17, 2001 9:47 pm Subject: Re: Stability, was: Re Ugly I have a model of the 31 foot twin keeler made of 3/16th plywood for the hull and 1/8th inch plywood for the decks and cabin giving the model the same vertical centre of gravity as the full sized shell. I gave it the same ballast ratio as the full sized boat in lead,and the equivalent sized mast in fir. In water I found it extremely difficult to get it to stay upside down . If I placed it very carefully upside down on totally calm water it stayed that way briefly. With the slightest disturbance, a half inch ripple for example, it would snap upright instantly.Waves big enough to capsize a boat wouldn't dissappear as soon as they'd done their dirty work, and the sea become instantly calm. If I tried , however, to place the boat down at an angle of say 5 degrees, it would right itself instantly. This example is just a shell. The full sized cruising yacht would have much greater righting ability, as %90 of the stowage in the boat is well below the waterline. As Bruce Roberts has well stated,everything below the centre of buoyancy in a loaded cruising boat counts as ballast ratio as long as it's well secured. When reality and theorie disagree , get real and trust reality. Brent Swain From: brentswain38@h... Date: Thu May 17, 2001 9:56 pm Subject: Re: Angle of heel Take a beachball. Superglue a 5% ballast ratio to one side . Throw it in water. Try to get it to float with the ballast side up for any length of time. The lack of any kind of keel ,half beam or whatever , doesn't change anything. This is a good example of how the shape and buoyancy of the submerged portions are a major factor in self righting ability. Brent Swain From: brentswain38@h... Date: Thu May 17, 2001 10:01 pm Subject: Re: Swain 40 ft? Plans for the 26 footer are $200, the 31 $300 ,the 36 $350 ,and the 40 $500. There are several being built in Nanaimo, one in Sechelt, one in Richmond BC, one in Terrace, one in Northern Alberta, etc. The boats all have positive stability to 175 degrees. Brent Swain From: brentswain38@h... Date: Thu May 17, 2001 10:07 pm Subject: Re: Boatbuilders in france using frameless techniques The only reliable standard for yachts is "what have they done, what punishment have they proven themselves capable of taking without structural failure , how many trouble free miles have they traveled." There is no mathematical equivalent of use and abuse in the real world . Brent Swain From: sunyataspirit@y... Date: Fri May 18, 2001 12:46 am Subject: Welcome Will! I'm happy to see that Will has climbed on board the group. His posts to the metal boats forum at boatbuilding.com were always a welcome addition and I'm sure his contributions here will generate some great discussions. I notice that some quite technical aspects of sailboat design have been forthcoming. Jeff, in particular seems to be very knowledgeable in this area and there have been some interesting points brought forth. On a less esoteric note, perhaps some of the more mundane details of rigging,types of rigs, interior finishing/plans etc. that Brent or any others have found to be of practical use may be offered up as grist for the group mill. I understand that the rig most commonly used by Brent is a staysail rigged sloop. How have you found this to perform ? How do the sailing qualities of the bilgekeeler compare to the fin keel, which I believe Winston Bushnell has chosen for his latest boat. Comments? From: Tasha Carleton Date: Fri May 18, 2001 5:56 am Subject: effects of steel hull on compass How is a compass affected in a steel boat, and can any problems with its use be corrected? Tasha From: willyacht@y... Date: Fri May 18, 2001 11:19 am Subject: Re: effects of steel hull on compass It can be corrected by swinging the compass yourself or getting a compass adjuster to do it for you, read all about it in Bowditch. You can use an electronic Compass like the KVH or a Gyro compass which self corrects. The KVH use microelectronics so is economical on power consumption, Gyros are still high current consumers. There are some advances like solid state gyros but these are still unproven. In the mean time make sure you get a good steel boat compass. But dont forget the basic techniques of using 3270 to get azimuth and swing your compass using a simple sundial. Will From: willyacht@y... Date: Fri May 18, 2001 11:22 am Subject: Re: effects of steel hull on compass Tasha Look at good compasses like the Sestrel Range, the Moore is a good steel boat Compass and does not have those huge compensator balls hanging about to hit you in the ribs when things get a bit rough. You can also mount you ordinary compass up the aluminium stick a bit to avoid problems. From: brentswain38@h... Date: Fri May 18, 2001 8:51 pm Subject: Re: effects of steel hull on compass Friends have had their compasses adjusted by professional adjusters. It's a tricky process. Personally I've never bothered, I've just took what it told me with a heavy grain of salt and checked courses with a visual backbearing when leaving port , and other alternatives. Handbearing compasses are useless on a steel boat. A steel boat will change a compasses reading from 100 yards away. Friends in California were discussing fluxgate compasses . When I asked them what it costs for a fluxgate compass they said $600 US. That is the cost of 6 GPS units. There is far greater likelyhood of a fluxgate quitting than all 6 GPS quitting.The GPS will tell you far more than the fluxgate will. The professional compass adjuster told us that fluxgate compasses created far more work for him than they took. He said people try a fluxgate for a while, give up on it ,then call him. With a GPS one can make one's own deviation card and adjust one's own compass. You can also constantly check the deviation at different angles of heel and on different courses , and have a pretty good idea of how things work before the power fails. Brent Swain From: burr.halpern@a... Date: Fri May 18, 2001 7:34 pm Subject: In response:Brent's reply on 'calculation'of structure and and stability.... Thanks for responding to my request for an explanation of your methods for calculating stability and structure. If I understood your reponse you basically do not calculate either, relying on the past perforance of prior designs to inform your decisions on new designs. That actually is abn age old and a very venerable approach to design. That said I seriously question your assertion that your boats "all have positive stability to 175 degrees" especially if that number is based on model testing rather than a static calculations or full sized vessel measurments. That is a very extreme stability that testing on real life vessels suggests just is not achieveable. The US Coast Guard did a lot of work on this issue in their efforts to construct their new rescue boats. These boats are designed to routinely self-right but the best they could achieve in real life testing of thier full sized vessels was in the 160-170 degree range. One of the interesting aspects of their studies was confirmation of the issue of scale in model testing for stability. Using very accurately scaled models the models performed as much as 20 degrees better than the final testing on full sized vessels. Still, even factoring in a correction for scale, if you can achieve a positive stability range to 150 degrees that is quite respectible and would be an exceptional performance for a steel hull and decked vessel. Respectfully Jeff From: "Alex Christie" Date: Sun May 20, 2001 3:51 am Subject: Swain 40 photo uploaded to group files - world premier viewing!! Dear Group, Met up with Brent the other day in Comox and bummed this great, never- been-seen photo off of him. After some wrestling with our local school's scanner, I have finally scanned the photo of the first 40 footer to be built, and it has been posted to the "Files" section in the album, "A Tongan Album". Brent met up with the 40 footer by chance on a Tongan atoll this year. Also encountered in the same atoll was a Kingfisher 20' twin- keeler. The Swain 40 featuress a pilot house, aft cabin, and I think twin keels, with skeg-hung outboard rudder. Rig is a sloop. The romance of the palm trees in the background is definitely hard to resist... Enjoy, Alex Christie (moderator) From: "David Hilliar" Date: Sun May 20, 2001 3:30 am Subject: Swain Designs Hi Is there a site where I can find out more about Brets Designs and in particular the 40 ft Design David From: willyacht@y... Date: Sun May 20, 2001 10:48 am Subject: Re: In response:Brent's reply on 'calculation'of structure and and stability.... Brents figures are obviously based on the pilot house structure and possibly the sealed off steel tube mast which can add as much as 20 degrees positive. As you know the pilot house can make the boat totally positive and self righting to 180 degrees. The British Pilot lifeboats and numerous Coast guard vessels use this to full effect. These larger rescue boats are harder to self right since they dont depend largely on ballast to self right. Yacht structures offer far less roll resistance. Many older traditional designs were self righting and had no negative stability, Marchaj documents this well in his books. There are a number of Pilot House Steel Designs from numerous designers who have figures in this range. You also have to factor in the narrower than normal beam in his Designs, this all can lead to good figures. But at the end of the day the best thing to do is pull the boat over and verify the figures. Anyway at least its better than the average steel or fibreglass boat. Considering that designs like Van Der Stadts and Roberts have figures below 120 most as low as 107 degrees, Brent has little to worry about. Will From: burr.halpern@a... Date: Sun May 20, 2001 4:20 pm Subject: In response to Will's comment on 180 degree positive stability I basically agree with much of Will's post but there are two points that I want to address further. In Will's post he wrote, "As you know the pilot house can make the boat totally positive and self-righting to 180 degrees." Actually, I don't agree with that. I occasionally attend the quarterly local SBYC (Small Boat and Yacht Council). The SBYC is made up of naval architects, yacht designers, and boat builders that primarily focuses (unlike SNAME, Society of Naval Architects and Marine Engineers)on the design of small craft. One of the more enlightening presentations was on the design and testing process for the Coast Guards new high hazard 43 foot rescue boat. (I believe two of these are deployed in your neck of the woods on the Columbia River.) These boats are aluminum 43 foot power craft. They are quite narrow when compared to 'normal power craft' and are closer to the hull proportions of a cruising sailboat. They are fully ballasted with a fairly deep keel plus they have enormous amounts of weight in the engines and tankage both of which are purposefully very low in the boat. These boats apparently have two configurations; with a sealed pilot house, and without a pilot house but with an windscreen and rigid hardtop. They were especially designed with a hull and deck shape, and weight distribution to have as close to 360 degrees of positive stability as is possible In these presentations, we followed the design from model testing, to the testing of full size vessels, to data gathered in actual deployment. In model testing and computer simulation, it was fairly easily to achieve positive stability approaching 180 degrees from either side. When the first boats were completed, the full sized boats were actually tested in a Bayou in Louisiana where the prototype boats were built. These were flat water tests in controlled conditions and roll over moments and angles were precisely measured. The boats were tested with varying configurations of fuel and water and were repetitively tested in conditions that were similar to those in the model tests. In the full sized boat tests, these boats did not accomplish 180 degrees of positive stability. The results variety from the best at somewhere in the high 160's degree range (the pilot house sealed and tanks empty which was a bit counter intuitive) to the worst somewhere in the low 120 degree range(pilothouse companionway hatch open and full fuel tanks). (For the record, I am remembering these angles off the top of my head and so I am not extremely confident that I am remembering the exact angle for the flooded pilot house) In any event, these were boats that were heavily ballasted. Their hull, deck and super-structures had been configured to promote righting. They had been designed to keep deck structure and deck hardware light as possible. With all of that, they did not achieve 170 degrees of positive stability in actual testing. I know this may be a distinction without much of a real world difference. One of the more interesting aspects of this testing was the affect of a flooded pilot house. These boats are designed to be able to knock down to a high angle without flooding their pilot house. They actually have watertight companionway hatches and climate control in the pilot house so that they can be completely battened down. In the discussion of the behaivor of these boats, one amazing thing was the really poor performance of these boats once the pilot house was flooded. This poor performance suggested the need to have a watertight door to the pilot house and to make certain that it is battened down in severe weather. The other point, I wanted to touch on was your comment the overall stability curves on Van DeStadt designs. You indicated that Van De Stadt's designs typically have 120 degrees or less of positive stability. I was wondering where that information came from. I know that they designed some IOR era racers that had comparatively small angles of positive stability, but I am under the impression that their current range of cruising designs have comparatively high angles of positive stability. [Van de Stadt also designed an Open Class 40, single handed ocean racer, with moveable water ballast, a canting keel and rig. This boat has a positive stability curve that defies the imagination and does infact have a range of positive stability (with the mast, water ballast and keel hard over to leeward) of less than 120 degrees but this is an asymetric stability curve that achieves positive stability at 175 degrees. These moveable ballast boats are an aberation in so many ways that I don't consider them relevant to this discussion.] Can you please elaborate on your source of information for stating that Van De Stadts have low angles of positive stability? Nothing that I have found suggests that to be the case. Respectfully Jeff From: "Alex Christie" Date: Sun May 20, 2001 9:23 pm Subject: Re: Swain Designs David, There is no site currently for Brent's boat that I know of, other than this one. The 40 footer is the same as the 36 and 31 footer in terms of construction methods, but is of higher displacement. Any specific questions you have about the 40 footer would best be addressed to Brent himself at brentswain38@h... When the 40 footer currently in the South Pacific returns to Vancouver later this summer, there will be a chance to get more information about its performance. I will try and get this information up on this site. Alex (moderator) From: turpin@y... Date: Sun May 20, 2001 10:22 pm Subject: Superstructure hurts stability, in the general sense There are two problems with the notion of using superstructure -- such as a pilothouse -- to increase stability. The first Jeff has touched upon: superstructure provides buoyancy when the boat is capsized only if it remains watertight. The very events that lead to capsize are also likely to lead to pilothouse flooding. In my mind, there is a larger issue. Adding superstructure raises the center of gravity, thereby hurting stability prior to capsize. Yeah,in theory, in may bring you back up in the rare event of a capsize. But the rest of the time, while the boat is upright, it makes the boat more tender, increases your roll angle, makes the crew less comfortable, and decreases the boat's ability to carry sail. Stability is not just about returning from capsize. There are lots of other ways that it is important to sailboats, at normal angles of heel. And in all those other ways, a pilothouse or other superstructure only hurts stability. Russell From: "Alex Christie" Date: Mon May 21, 2001 11:21 am Subject: Wheelhouse and stability Thank-you Russell for raising the superstructure-weight issue, as it is a good one to air in this forum. I'm glad we are all having fun, and the debate is lively with good sports all around. I'm sure Brent has something to say on this, but I'll stick my oar in for the moment, and he can deal with the aftermath! Russell has asserted in his post, > In my mind, there is a larger issue. Adding > superstructure raises the center of gravity, > thereby hurting stability prior to capsize. By all means no one should load on weight up high on a sailing vessel willy-nilly, without thought; this is an excellent theoretical guideline for designing a sailing yacht, and should always be kept in mind. However, I might point out that any significant effect of the application of this theory more accurately applies to boats with quite large pilot houses bristling with various gear, and not much to Brents boats "as designed" (owner-builders may do differently, but this is out of Brent's control, and this can be debated in a different string). To meaningfully debate the valid point Russell has raised, we must focus on the actual vessel in question rather than any generality, because the differences may be significant. [It may be useful at this juncture to go back and take a close look at the photos of Brent's own 31 footer in the files section in order to properly understand the meaning of this post.] In practice, Brent's designs purposefully have very minimal, low- profile pilot houses which may be more accurately described as a raised section of the main cabin. They are integrated with the main cabin, whereas regular pilot houses are usually a separate area with a raised floor, sometimes with the engine underneath. Brent's boats usually have the engine further aft, and the pilot house floor occupies that vacated zone that would be otherwise occupied by a diesel in the average pilot house yacht. I recall standing in that raised section on a 36 footer (Costa Vida) a few years ago, and noting that the main cabin floor was only a step or so down, maybe 6 to 8 inches lower (Brent or another owner might be able to correct this number). The raised cabin roof/pilot house has a minimal band of extra steel (punctuated by regular swaths of plexiglass, which is of course lighter than steel) to gain that height, so there is not much extra weight in it that the cabin roof wouldn't already have if there were no pilot house and the cabin roof were all one height. As to the integrity of the pilot house upon capsize, the aft door- hatch on Brent's boats built as designed easily seals off the vessel from the outside world with the rubber gasketed aluminum 1 piece doorway which dogs down tight in an instant. As long as this hatch is closed when the boat goes over, there will be no gushes of water getting in that house. In conditions where a capsize is bound to occur, a person should be steering from inside, in any case, not standing vulnerably outside waiting to be washed away, or fiddling with drop-boards with numb hands. A vessel with only drop-boards, or flimsy wooden louvered doors seems dangerous in bad conditions in comparison to the Swain hatch-system . I like how just a small bump on the aft edge of the pilot house is raised to accommodate this hatch, instead of raising the entire roof level to fit the hatch, an feature which consciously addresses the concerns previously raised in the other post. Very few yachts sport hatches like this, though they should. Amidst the fury of a full-blown gale in the middle of the Pacific Ocean I would find such a thing very confidence-inspiring. Alex Christie (moderator) From: willyacht@y... Date: Mon May 21, 2001 12:48 pm Subject: Re: In response to Will's comment on 180 degree positive stability Interesting data, i must accept the results from the real world testing of those particular boats. These testing results will vary from design to design of coarse. This fact as we know all points to the designer doing his job correctly in the first place and subjecting all designs to a full stability study. Something that some refuse to do, in my opinion totally unprofessional these days with ample computer power and stability software suites that kids in grade 5 can use. As for the Van Der Stadt Results, i have been involved in building and having these vessels accepted for survey. I have full stability curves for most of their recent designs on file, 34,37 40 etc. They dont release their results, but in the cases i was involved in they had to. VS 34 125 degrees in steel VS 37 107 degrees in steel VS 40 120 degrees in steel Aluminium figures are slightly better. It is fortunate for the likes of Van Der Stadt and Bruce Roberts that there designs are not being commercially built, since this would have revealed fully the true figures. In most cases after doing a incline test most faired worst when fully loaded for cruising. These figures are poor in my opinion but are typical for steel vessels. I must emphasize that i am not taking pot shots at them particularly, but in general most steel boat designs have poor static stability. If you have more current data please let me know. I would be happy to retract my statements and discard any of the obsolete data files. As for "recent" cruising design yes i will agree that most have better than average stability but these are mostly the large production boat companies wanting to meet CE requirements. In my opinion the rude awakening as only occured in the last 18 months. Very few one off and limited production designs have altered their designs in any way. The figure of 120 degrees was the norm and this does not alter the fact that the vast majority of the production fleet have below average static stability figures. These figures are born out in US Sails extensive IMS database. I would not be concerned in 45 ft plus boats, but anything below that is risky. You can look at many so called legendary cruising designs that have dismal static stability figures. But if i was a cruising sailor in the market for a large cruising boat i would look at one of the latest IMS designs because they certainly state of the art in terms of structure and stability. The last Sydney to Hobart race fleet put most of the current cruising fleet to shame in terms of overall seaworthiness, considering they were considered extreme go fast boats. Any of these current IMS designs i would be happy to cruise in with a few more ammenities. You can still pick up any issue of Cruising World and you can still find reviewers commenting that 120 degrees offers a good safe range. This opinion is still held by the vast majority of so called "cruising experts". Considering that most of the current IMS fleet will be hovering above 140 degrees one wonders what kind of elephants foot you need bring to bear to convince cruising sailors and designers of the overall merit of safety through stability. Two Sydney to Hobart disasters have made race designers think again and most owners who have been there have agreed. I am only concentrating on static stability since this represents a major weakness of cruising designs at the moment, we all know there are more sophisticated methods for determining the vulneribilty of yachts to capsize. These methods are well understood by most stability experts even though they are complicated to calculate. Concentrating on the capsize angle gives us goal posts to aim for, when we meet these minimum goals we can refine the models and definitions upwards or downwards. In the mean time hopefully it will save some lives and stiffle unhealthy commercial developments which have little real regard for some peoples safety. Will From: turpin@y... Date: Mon May 21, 2001 2:39 pm Subject: To be clear, I'm not arguing against pilothouses Pilothouses have lots of benefits. A dry, comfortable watch spot is very important. And I see the advantage of a navstation up where the watch is, rather than requiring the watch to duck below in order to navigate or update logs. Though you don't want the watch spot too comfortable, and to tell the truth, in the middle of the night, it's nice to have a duty that takes you below once or twice an hour. You have to move around a bit on those night watches. I was NOT arguing that pilothouses are bad. I was pointing out that pilothouses put weight high, which is a disadvantage that the designer accepts for their benefits. From: "Alex Christie" Date: Mon May 21, 2001 5:42 pm Subject: my point being that not all pilot houses are alike... I understand that Russell was not against pilot houses per se, but I was pointing out that it is important to note that NOT all pilot houses are built alike, and that in Swain boat, the pilot house is more accurately just a raised portion of the cabin roof with small windows in it rather than a wholly separate structure. Further to this point, in Brent's case the pilot houses are usually lower than most, so as to minimize any disadvantages they may cause in return for their benefits. I agree with Russell as to the effect of weight up high, and I think we can concur that this is not a point in dispute. I think we've all seen some sailboats (and powerboats) with ridiculous amounts of aptly- named "top-hamper" which truly "hampers" the ability of the boat to function safely and comfortably. As a final anecdote in support of Russell's point about excess weight up high, I once saw a home-built steel sailboat at dock in Belleville, Ontario which had an enourmous tall, boxy full-width steel cabin (no walk around side decks). Even tied up to the dock it looked dangerous and unstable, for though there was almost calm water in the harbour, and there was no wind pushing on the rigging, the vessel was rocking (lurching, more like it) slowly from side to side in a most curious way, as if it were constantly trying fall right over. It would move through top dead centre, then drop quickly until it picked up some secpndary stability from the hull, bounce off that and come to top dead centre before "falling" the other way. It gave me the creeps watching it. Even with extra stores aboard, secured down low, what would such a vessel be like at sea? I have not heard of any of Brent's boats exhibiting this behaviour! Alex Christie (moderator) From: pvanderw@o... Date: Tue May 22, 2001 3:26 pm Subject: Tanton On the bulletin board at http://www.tantonyachts.com/, Yves-Marie Tanton notes that he has just sold plans for a 50' Steelstar that he calls an origami boat. How similar the constrution is to anyone else's view of 'origami,' I don't know. On the home page, there is a link to a descripton of his 60' Steelstar, which might help visualize the 50-footer. Tanton has designs for several small (e.g. 30-35') yachts of steel constrution as he likes to design for metal. Peter From: "John " Date: Tue May 22, 2001 6:22 pm Subject: Paint The company I work for is opening a Marina/Boat yard. I was asked to find a school that would train our marina workers in the fine art of painting Yachts. The parent co. is a modest sized shipyard and has a pretty good handle on the Painting of steel boats (Navy ships), We need instruction in fiberglass painting, gel- coat/blister repair, Any suggestions would be appreciated? John From: brentswain38@h... Date: Tue May 22, 2001 7:46 pm Subject: Re: To be clear, I'm not arguing against pilothouses The weight of a pilothouse is largely offset by the increase in storage for heavy items below the raised pilothouse floor. With a steel pilothouse the ultimate stability of a boat is greatly enhanced by the buoyancy of the pilothouse when it begins to submerge in a knockdown. The pilothouse on my 31 footer has 2,300 lbs of buoyancy , which is the equivalent of adding 3,000 lbs of ballast when it is submerged. The risk of a man overboard situation is greatly reduced by the crew spending that much more time in the pilothouse and that much less time on deck. The risk of hypothermia and clouded thinking caused by exposure to the elements is also greatly reduced.This makes the pilothouse a major improvement in the safety factor. A serious offshore cruising boat without a pilothouse may be as logical as a pickup truck which can only be steered from the open box. Would you buy such a pickup truck? Brent Swain From: "John " Date: Tue May 22, 2001 8:40 pm Subject: Re: To be clear, I'm not arguing against pilothouses > > I was NOT arguing that pilothouses are bad. I was > > pointing out that pilothouses put weight high, which > > is a disadvantage that the designer accepts for their > > benefits. A little grist for the mill. I built a Yawl, many years ago, 40' steel hull w/ an aluminum pilot house. It took just two men to set it in place. Much lighter than Cor- ten, John From: "Alex Christie" Date: Wed May 23, 2001 1:13 am Subject: aluminum pilot house attachment Further to John's mention of aluminum pilot houses, I recall reading in a Jay Benford book about a special metal strip which is made of aluminum on one side, and steel on the other, explosively bonded together. The strip is used to join the aluminum pilot house to the steel deck, each metal then welded to their respective parts. The use of gaskets, bolts, isolating inserts and such is avoided. If you wanted to go this route, I'd expect it to cost more, of course. Brent's wheel-houses don't seem to need it, but it is a possible option. Alex Christie (moderator) From: willyacht@y... Date: Wed May 23, 2001 10:05 am Subject: Steel Masts? What are the opinions on steel masts? Has anybody lost a steel mast in heavy weather, or experienced a severe knockdown? What are the typical diameters and wall thickness for different size boats? Has anyone calculated the inertias for typical off the shelf tube sizes and compared them to the equivalent aluminium yacht sticks? Any other info and opinions would be helpfull. Will From: "Alex & Kim Christie" Date: Wed May 23, 2001 11:22 am Subject: Re: [origamiboats] Steel Masts? Steel masts have been used on many Swain boats with success. The 40 footer seen in the photograph just uploaded to "A Tongan album" uses a steel mast (something like 53 feet long!). Brent has all the specs on this stuff. I know of two other boats, 36 footers, which used steel masts, and one of them has circumnavigated. Unfortunately I don't have them on board our group yet, as it would be very interesting to hear about their offshore adventures. Alex Christie (moderator) From: "Chris Rueckert" Date: Wed May 23, 2001 11:49 am Subject: Re: [origamiboats] Steel Masts? Apart from common mast-profiles there is a "new" idea under investigation here in Germany. at http://gittermast.beti.de you will find a description of a "Gittermast" which means "lattice tower" in english I think. However, it is constructed in a similar way as traverses in the field of Stage-constructions. Due to its construction it shall be as light as a Al-Mast though being welded of steel. According to the author of this site the disadvantages are only that it cannot be trimmed backwards and its unconventional look. Chris Rückert From: "John " Date: Wed May 23, 2001 1:34 pm Subject: Re: aluminum pilot house attachment The bi-metallic strip is used by the navy to attach alum superstructure to the steel main deck. Its avail from Pacific Aerospace and Production supply. It is rather expensive owing to the explosive bonding process. about $85.00 LF John From: pvanderw@o... Date: Wed May 23, 2001 1:50 pm Subject: Re: Steel Masts? > at http://gittermast.beti.de you will find a description of a "Gittermast" which means "lattice tower" in english I think. Very interesting. It would have the advantage that it could be tapered if desired. And a home welder could possible build one at home. However, I suspect that it has very high drag in the wind. From the standpoint of windward ability, I suspect that some fairing would pay for itself. Peter From: F.Ake@g... Date: Wed May 23, 2001 2:40 pm Subject: Re: Steel Masts? > home. However, I suspect that it has very high drag in the wind. > the standpoint of windward ability, I suspect that some fairing > would > pay for itself. > > Peter According to the author of the refering site it is the fact that it is not faired giving advantages. He arguments, that the resistance towards wind is rather less than the one from a conventional mast as the tubes are rather small compared to the gaps in between. He reports that his sails are staying excellently as even the Front-edge of the sail is not under coverage of the mast. Apart from that it might be an advantage that jeers and cables can be put inside and you can climb up the mast in case you have to (repairing top-light or getting back a lost jeer). From: willyacht@y... Date: Wed May 23, 2001 2:44 pm Subject: Re: Steel Masts? Very interesting, in the early 70's and late 80's there were a few boats here in Australia floating around with steel lattice radio tower masts. These were very heavy, but now there are new aluminium lattice mast sections radio and structural that could do the job. My main interest is to build a mast that can realiably take a roll in heavy weather. Most mast calculations are for the XX and YY inertias and very little consideration for the forces of accidents. Some yacht mast sellers seem to accept the fact that your mast will fall down in a knockdown. Various structural engineering experts have stated that its impossible to prevent mast loss in a severe knockdown and roll. I always remember Bernard Moitessier and his telephone pole masts surviving extreme conditions. Having lost 2 masts that were very well engineered sailing between Australia and South Africa, i am getting sick of shelving out money for masts, let alone the living hell it causes sailing under jury rig. I have thought about a oversize free standing carbon fibre mast and then staying that. But this cost is high for a one off. Maybe i will find a aerospace left over laying on a Pacific atoll made of titanium!! Will From: pvanderw@o... Date: Wed May 23, 2001 3:39 pm Subject: Re: Steel Masts? > He arguments, that the resistance towards wind is rather less than > the one from a conventional mast as the tubes are rather small > compared to the gaps in between. I don't think that I can accept this without experimental evidence. Most books on sailing aerodynamics show a comparison of two sections with equal drag: one round, and one foil shaped. The ration is size is about the same as the ratio between the tubular parts to the overall mast section of the glittermast. All joints have high drag as well. I know that aluminum masts don't always present a good foil section to the wind, but still..... Peter From: pvanderw@o... Date: Wed May 23, 2001 3:42 pm Subject: Re: Steel Masts? > I have thought about a oversize free standing carbon fibre mast and then staying that. How about going with a gaff rig? The mast would be much shorter, and therefore could be heavier. Peter From: cdbarry@h... Date: Thu May 24, 2001 2:02 am Subject: Re: Steel Masts? --- In origamiboats@y..., willyacht@y... wrote: > What are the opinions on steel masts? In a stayed mast, buckling dominates. This is in turn controlled by the ratio of density to Young's modulus. This ratio is actually slightly higher for steel than aluminum, so theoretically steel is a better material for stayed masts than aluminum - given the same OD the wall thickness is 1/3 for the same compression strength. However this results in quite thin walls which in turn presents fabrication problems, vulnerability to corrosion, and possibly local buckling limits. Steel is also just generally difficult to deal with because extruding it is much more difficult. On the other hand, it doesn't suffer from HAZ due to welding. At some size, steel is probably a better choice than aluminum depending on many other factors. Just run the numbers for your case and find out. From: cdbarry@h... Date: Thu May 24, 2001 2:21 am Subject: Re: In response:Brent's reply on 'calculation'of structure and and stability.... Hi Bruce; Weren't you at the SBYD meeting that Dave showed the 47 MLB full size self-righting test videos and model tests? 44s, 47s and 52s all self right through 180 as predicted, and measured forces on the 47 matched calcs quite well. There are also self-right CASREPs on 44s and 52s that show they self-right in practice as well, though it's not fun. If not, get in touch with me sometime, and maybe I cen get you a chance to see them, or I can bring them by an SBYD meeting. Actually though, full 180 degree self righting is probably not absolutely necessary as the probability of rerighting after capsize is related to the inverted and upright energy ratio, and the probalistic energy content of the waves. It's pretty simple to figure the probablity of rerighting in a given time. I think that the issue is to make sure that inverting doesn't result in serious damage or flooding, so I'm fond of watertight subdivision. Chris From: cdbarry@h... Date: Thu May 24, 2001 2:29 am Subject: Re: ABS? -- In origamiboats@y..., willyacht@y... wrote: > I read with some interest the posts on ABS construction standards, > ABS is an obsolete standard for pleasure sailing vessels. Even in It was Journal of Ship Research, however, note that the data was based on yachts that came home for the damage to be measured. The steel boat in question had plating deflection in the plastic range, (from which the loadings were determined) but no penetrating hull failure. In my book, this counts as doing its job. Also note that there are "Guidelines .. Racing Yachts", "... Motor Pleasure ...", "... High Speed Craft ...", "... Fishing Vessels..."and "... Small Steel ..." Which rules are you thinking of? From: willyacht@y... Date: Thu May 24, 2001 12:36 pm Subject: Re: ABS? ABS Guide for Building and Classifying racing yachts, 1986. ABS no longer supports and gives rulings on small sailing yachts. So to me the standard is obsolete. You knew of all the past problems of ABS classification, in that the standard was wider than the barn door. Numerous structural failures all which complied with ABS guidlines. It was only a handfull of designers who submitted their plans for full plan approval even then failures occured. So if you think this is good engineering practice to design yachts to an obsolete standard so be it, you are qualified in this exact area. So to me if a case of structural failure occured and was brought in front of a court, needless to say i would think the designer would loose. Numerous out of court settlements with Lloyds plan approval process have set legal precident in this regard. Lawyers 1 designers 0. Anyway if you designing a steel or aluminium sailing yacht maybe you can brief us on what current standards you would use. At the moment there is a void as far as steel and aluminium vessels are concerned under 60 feet. I know in past post you have touched on Coast Guard NVIC guidelines but these are not widely understood and used. Will From: willyacht@y... Date: Thu May 24, 2001 12:43 pm Subject: Re: Steel Masts?Wylo Nick on Wylo is a firm advocate of the GAff rig, it seems to be gaining popularity. I have also seen some analysis that give the edge to the Gaff on many points of sail. Problem is breaking habits and conformity. Shedding weight on the Gaff rig seems to be a problem, i would not be hesitant to use it if owned a Bristol Channel Cutter. Will From: brentswain38@h... Date: Fri May 25, 2001 1:27 am Subject: Re: Steel Masts?Wylo Most of my 36 footers have been using 5 1/2 inch to 6 inch OD steel masts with a 1/8th inch wall for many years and have crossed a lot of ocean with them with no regrets.All say they'd do the same again. If you make the mast airtight, corrosion on the inside is impossible once the oxygen is used up. You could empty your CO2 fire extinguisher inside before sealing her up, but as no one has had any problem there , that would be overkill. Sealing the mast also gives it positive buoyancy when submerged which can add 4700 ft lbs of righting moment in a knockdown, something people with internal halyards in an aluminium mast seem to have overlooked. We've always used round tubing, which is not the ideal shape structurally, but it costs about $1000 dollars CDN for a fully detailed mast counting labour and materials. Round tubing can be squashed into an oval for a small fee if you can find a brake with a 20 ft bed. Most large cities have them. As steel boats with proper metal hatches can be made as watertight as a pressure cooker, and it's pretty hard to punch a hole in 3/16th plate in a boat under 50 feet,watertight bulkheads seem rather pointless, a throwback to wood and fibreglass boat thinking. Brent Swain From: "John " Date: Fri May 25, 2001 3:45 pm Subject: Re: Steel Masts?Wylo --- In origamiboats@y..., brentswain38@h... wrote: You could empty your CO2 fire extinguisher > inside before sealing her up, but as no one has had any problem there A two or three volume change w/ Nitrogen rather than co2 would remove most of the moisture in the tube as well. John From: sunyataspirit@y... Date: Fri May 25, 2001 3:58 pm Subject: Brents book; I've just received my copy of Brents book and it's a great read, full of advice, information and suggestions for the home builder, plus it answers many of the questions posed on this group. The KISS principle advocated by Brent makes a great deal of sense, especially for the budget minded builder, and for those of you south of the border where your dollar is worth 50% more than ours,I would suggest the minimal cost of the book makes it a must buy. Cheers, Richard From: cdbarry@h... Date: Fri May 25, 2001 7:18 pm Subject: Re: ABS? I don't think that the 1986 rules are the most recent, but I am satisfied that, given correct detail design, the last version of ABS ORC is adequate. The failures that I have heard of have involved incorrect detailing, which is not specifically addressed by the rules. Inshore vessels should probably use the urrent DnV tentative rules. I am also basing this on a first principles analysis of North Pacific SF/Japan passage of a 40 foot cruising yacht, using real probablistic weather files and actual motions data that Young, Sircar and Myself did in 1982 for a AIAA/SNAME paper. If the craft in question was somewhat faster, the HSC rules are applicable, either DnV or ABS. There also was a paper presented at the most recent CSYS. It showed measured data for long racing passages that met ABS/DnV pretty well. I think that Joubert's pressures are applicable to control of actual tensile membrane failure, not initial deflection, which is the ABS failure criteria. A designer may want to also do such ultimate strength analyses using Joubert pressures, (this is analogous to post failure plastic hinge analysis for seismic loads in buildings) but this is fairly difficult without quite sophisticated tools. The one CG requirement for metal structure is NVIC 11-80, which is actually very easy to use, but of limited applicability. From: cdbarry@h... Date: Fri May 25, 2001 7:20 pm Subject: Re: Steel Masts?Wylo The standard commercial method is to fill with preservative oil and drain. Another commercial technique is foaming them. Both are used for skegs, rudders, etc. From: willyacht@y... Date: Sat May 26, 2001 9:26 am Subject: Re: ABS? I will accept your arguments CD, i have all the updates to ABS rules but they still obsolete. My only point is that ABS as a design standard is obsolete for sailing yachts. ABS no longer develops standards for sailing yachts regardless of the material. Be that as it may steel yachts built to ABS have a good track record, but would it not be prudent for any designer to update to the latest design rules and standards? Will From: willyacht@y... Date: Sat May 26, 2001 4:39 pm Subject: Re: Steel Masts?Wylo It would not be hard to get these kind of tubes galvanised or spray metalised. An expoxy coat over this would ensure long life. Anyway i will be trying this sometime on one of Brents 36 footers. Will From: willyacht@y... Date: Sat May 26, 2001 4:48 pm Subject: Re: Brents book; I agree its a great read, his experience certainly show through. Comparing Brents book to one well known metal boat author is like comparing gold nuggets to donkey poo, Brents being the gold Nuggets. The same rehashed magazine tabloid style material from others with very little experience becomes boring very quickly. Brent should be encouraged to expand on his work and fully publish his book. It will be a hit. I think there is a eager audience out there for that kind of book. 5 stars Brent.. Will From: cdbarry@h... Date: Sat May 26, 2001 6:53 pm Subject: Re: ABS? Until the new ISO standards come out (which is one reason ABS let it slide) ABS is a good one. After all, the nature of the ocean and steel hasn't changed too much in the last couple of years. From: "Paul Liebenberg" Date: Sun May 27, 2001 1:37 am Subject: Brent Swain 36 for sale. Hi Everyone, I am selling my swain 36 hull. It is nearing completion of the steelwork and will be ready for foaming and painting this summer. The hull was pulled together by Evan Shaler, Detailing by Brent. I'll post some pictures in the files section, but for furthur details, contact me at zelda@island.net or 250-923-9122 From: Zelda@i... Date: Sun May 27, 2001 1:58 am Subject: re: boat for sale Pictures of my hull for sale are already in the files section. Paul From: "Scott Yanke" Date: Sun May 27, 2001 3:21 am Subject: Re: [origamiboats] Brent Swain 36 for sale. how much, and where is it located? From: "Paul Liebenberg" Date: Sun May 27, 2001 3:36 am Subject: Re: [origamiboats] Brent Swain 36 for sale. I am located in Campbell River, on Vancouver Island. I am asking $30,000 and will take all offers seriously. Paul From: "Alex Christie" Date: Sun May 27, 2001 9:27 am Subject: Images of Paul's boat For convenience, I have moved the listing for images of Paul's boat to the top of the files list to make it easier for interested parties to find. Alex (moderator) From: "Alex Christie" Date: Sun May 27, 2001 9:41 am Subject: 40 foot Swain "MISHAR" in South Pacific The first 40 foot Swain, which I have since learned is called MISHAR, is currently at sea in the South Pacific. I have found out that we can track her and Mike's current movements as she makes her way through the South Pacific, eventually heading home to BC. She has just left Aitukaki enroute to Penryn. Go to the site, http://www.bitwrangler.com/yotreps and look up Mishar's name and call number (KD7 MLW) and you can find her reported positions, speed, current weather and sea state. Other vessels are listed too. Pretty cool. I'll use this site to track her right back to BC, then I'll be waiting on the dock when she arrives so I can get some more pictures...and maybe a ride! Alex Christie (moderator) From: burr.halpern@a... Date: Sun May 27, 2001 5:03 pm Subject: Questions about Swain 36 for sale. Looking at the photo's, it looks like you have done a very nice job of building the boat so far. I have a couple questions that I guess I just have to ask. In earlier posts it has been suggested that these boats should cost a total of about $35,000 Can. to build. At this point it is not clear how much you have completed besides the hull, but how much money would you estimate would be required to complete the boat from this point? If a whole boat is supposed to cost $35K why are you asking so much for your hull (or is there more than a hull here)? It has been suggested that these boats should take as little 5 to 6 weeks to complete to the point that they are ready to sail. How long have you been working on your boat and how much time do you think it should take to finish her? And lastly, Why are you selling at this point in the project? Respectfully Jeff From: "Paul Liebenberg" Date: Sun May 27, 2001 5:37 pm Subject: Re: [origamiboats] Questions about Swain 36 for sale. Hi Jeff, I'd rather negotiate price on an individual basis, but judging from your previous posts about steel boats I suspect that you are not a not a potential buyer. I am selling because the boat does not meet my needs. I need/want a bigger boat. It is a nice fair hull and I have no reservations whatsoever about the construction method. My next boat will hopefully be of the folded steel variety. I am asking $30,000 because that is what I estimate has been put into the boat. Anyone who buys the boat at this point will get a nice hull and save a lot of time. If anyone is interested, give me a call or stop by and see me, I'm in Campbell River. Paul Liebenberg From: svbanshee@y... Date: Sun May 27, 2001 9:34 pm Subject: Re: Jeff's Questions about Swain 36 for sale. Jeff forgot to add that he has a boat (Laser 28) for sale as well. It's made of fibreglass... Tasha From: burr.halpern@a... Date: Sun May 27, 2001 10:08 pm Subject: Actually the boat that I have for sale is not fiberglass... I am selling a Laser 28 but these boats are not actually fiberglass, at least not during the period that my boat was built. My boat actually is Kevlar with vinylester resin. The Laser 28's were the first production boats built using two part vacuum molds and Kevlar. Both are a bit more popular today. Jeff From: burr.halpern@a... Date: Sun May 27, 2001 10:19 pm Subject: Re: Questions about Swain 36 for sale. You are correct that I am not a potential buyer.I am actually in the middle of a deal on similar sized boat. The reason that I askec the question is more for general knowledge for myself and for others who read this board. As I see it, this is a board that is visited by people who are interested in home building boats and it sounds as if some of them are considering building folded steel designs. If someone is considering building a boat it is helpful to hear information from someone who is actually going through, or has actually been through the process of purchasing the materials and doing the work. I think that your experience and observations would be helpful. I though some kind of estimate of you overall time and costs for such a project would help others evaluate whether this makes sense of them and to some extent would allow a potential buyer to get some sense of what is involved in finishing the job you started. While I am not a fan of steel, (it is probably the last material, except for ferricement, that I would consider for a boat under about 45 feet) I am still very interested in the construction process for any material. My questions were not meant in any kind of negative way. I was just seeking a little more knowledge from someone who has actually 'been there'on a steel boat. Regards Jeff Mon 5/28/2001 From: Date: Sun May 27, 2001 11:02 pm Subject: New file uploaded to origamiboats Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the origamiboats group. File : /Kerrera -- a Swain 36/kerrera2.jpg Uploaded by : ravencoast@t... Description : Kerrera on the hard From: "Alex & Kim Christie" Date: Mon May 28, 2001 1:16 am Subject: Two other Swain 36 completed yachts for sale Dear group, With thanks to Richard Wilford, here are two adverts for 36 foot Swain yachts, one in BC ($74,000 Canadian), the other in Scotland (approx. $110,000 Canadian). I nabbed all the photos of these vessels off their respective websites for our files Kobella - 36 foot Swain (fin keel) for sale in Maple Bay, BC http://www.maplebaymarine.com/Kobello/kobella.htm Kerrera - a Swain 36 (fin keel) for sale in Scotland, U.K. http://www.hcs.dial.pipex.com/kerrera.html Alex Christie From: "Alex & Kim Christie" Date: Mon May 28, 2001 2:19 am Subject: Hull materials. There is no Ultimate Re: Jeff's questions on Swain 36: I know your question was meant in a neutral way, Jeff, but perhaps your previous posts against steel as a hull-building material set you up. It might have been something to be expected, considering this is a steel-boatbuilding forum(!). That said, thank you for clearing the air by indicating that your interest was genuine and in the spirit of enquiry that this group is meant to promote. Most on this forum accept that a yacht can be built successfully of steel, hence their interest in being here. The forum attempts to distribute and share information about building steel yachts, in this case using the origami methods. Tasha, whom I know personally, knows too, that fibreglass boats come in all shapes and scantlings, and additionally have circumnavigated successfully, including polar passages. I think she was havin' a bit o' fun here, cuz I know she still sails an Albin Vega (fibreglass, and the type has circumnavigated!). She's a devilish card, that one, and I am going to enjoy having fun at her expense next time I see her on the water or in the pub [where are you anyway, Tasha?]. Sorry Tasha, its my job as moderator to set the record straight -- you can't hide! ;-) (to be fair, I believe Tasha is contemplating building a new liveaboard in steel using Brent's methods) As we all know, it is possible to build excellent boats from a wide variety of different materials, and that includes wood (my training is in traditional wooden boatbuilding, with some composite work), steel, fibreglass, aluminum, plywood, reeds, beer-kegs (a catamaran was built using these in Japan), and even Ferrocement. It is how the chosen material is used, rather than solely the material itself, which determines whether the boat is "good" or not. I simply do not think there is any "ultimate" material out there (that is in the realm of affordability for us non-royals here in the colonies) for boatbuilding. Some materials excel at certain things, but rate poorly in other areas, and that is just the way it is. Every material has its detractions for various reasons -- mostly because the caustic and energetic marine environment exacts a high price upon our beloved creations. It is a matter of working around the limitations with proper engineering and forethought, as well as utilizing the constant feed-back available through true-experience. If we work with the nature of the material, then we can build a good boat. We can debate the relative merits and detractions of various materials, but it would be a foolhardy proposition to state one material the "ultimate", though we proceed to do so anyway! Brent must be acknowledged for the fact that he has always tried to improve his boats by using feedback from his own experiences, and that of owners. It is for this reason that his guidebook has some really unique solutions to problems in steel boatbuilding that most designers never pay attention to. One of the examples is his solution to the scupper-drain-stain seen on the hull-sides of many yachts (not just steel ones). We've all seen those ugly stains on the sides of boats, but he's found a simple way around it. Builders can ignore his advice, but they do so at their own risk. As an aside to Ferro cement, I don't plan to build a boat of this material in the near future, but I am not going to slam it, though I used to. Go slam the builders (and some designers) who ignore current knowledge on how to properly use the material for the greatest benefit. Anyone with a modicum of knowledge in engineering knows that just about any material, including ferro, can be engineered to make an excellent boat. Engineering departments at universities make great sport of requiring their students to accomplish unbelievable tasks with common materials. Put "concrete canoe" in any search engine and have a read -- it is quite interesting (they are lighter than you think, yet still fulfill strength requirements). Jay Benford spent some time working out proper scantlings for some of his designs to be done alternately in ferro (cutter Mercedes). That is what the challenge of engineering is all about, and what a wonderful challenge it is [insert stirring music here]. Someone could say, "I want to build a boat using dried banana peels, corn-husks, baler-twine, and epoxy"; the marine engineer will work out a way to make it happen, and it will likely work, maybe at considerable expense, but you never know...); if it didn't work, then usually the engineering is at fault, not the material (yes there are limits to what material can be used, like building a boat out of, say, water, nitrogen, or other such things). Anecdote: There is a fine ferrocement cutter in Victoria, originally built in Holland to Lloyd's specifications and a gold-plater finish. I thought it was glass until the owner informed me otherwise. I know, it is only one winner among many flops, but it still tells us to open our minds to this fact: you just can't judge a boat by its material alone. My later grandfather, a professional forester at UBC in Vancouver, worked at devising boats made of paper. His detractors must have thought him half-mad. If only he could have lived to see the wonders of composite boats that his paper boat idea was in some way a precursor to! Alex Christie (moderator) From: "Alex & Kim Christie" Date: Mon May 28, 2001 1:22 am Subject: Determining costs for hull building Costs of building: It certainly must be hard to quantify how much goes into a home-built craft, when building in any material, because it is so dependent on the individual boatbuilder, their resources, and what resources are available to be had for building the vessel (and at what price). This is likely what drives varying numbers reported for hull construction. Ultimately you do what you have to do in order to get the thing built. Time spent on labour has value, and so should be added to the cost of the boat if you are selling it partially built. Brent's boats lend themselves particularly well to the scrounger because they use materials which can be found in non-marine product environments (scrap yards). Other boat designs may benefit from this as well, but to a lesser degree. Epoxy, for example is not usually found cheap, nor is clear boat lumber, but there are other items which can be scrounged for these types of boats too. Expressed genuine interest in what time and costs are involved in building a hull has some merit here, and may help people plan out their time and finances before engaging the project. It would be interesting to break down the yacht-building process into stages and collate data for time and money spent, and post this as a chart. I'll keep my ears open on this when I talk to builders in the future. I'll create a folder in the files at some point, and others can add to it as they go, should they wish. Alex Christie From: willyacht@y... Date: Mon May 28, 2001 2:24 pm Subject: Re: Questions about Swain 36?/Economics Regardless of what material Jeff likes or dislikes. We need to dig deeper into our emotional reasons why we do what we do. The arguments for and against steel have been settled have been done over a million times. Advocates of each think they have the battle won. Now back to the emotion.... Simply put most dreamers and can do types simply dont have the money to engage a NA to design or even purchase a hull advocated by Jeff fullstop. I cant even recall when i last saw one of these hitech hulls in Reunion, Capetown, Chrismas Islands, or wherever your favourite remote cruising ground is. Yet i see plenty boats with people who only have the basic means to deliver their dreams. I always marvel that they have been on the water for years and some are on third and fourth circumnavigations. Hey whats all that noise, its six in the morning, head out of the hatch, JeeeeeSUS what the hell its a hitech aircraft carrier French hull with maybe 12 crew. MMMMMM formalities out of they way, Oh you only staying one day "we in a hurry because the owner has to be back in France to run his dot com business and is only on this one leg". This is the typical routine for these high pressure types with their hitech boats, and surely this is not the lifestyle or cruising style that most who build boats or scrape and save dream about. To most the boat is an means to an end, and so long as it meets the basic survival criteria it will do. By enlarge metal boats feature heavy in this thinking. Just like the vast majority drive everyday automobiles, only a minority of archair warriors dream about Porsches knowing full well they will never use it to its full capability or can hardly afford it, and is beyond the role of basic transportation. If you are one of these dreamers you will never get away, because your funds will be totally exhausted, with cost overruns, and technical developements on the fly taking this hitech approach. When the hull cracks are you going to fly the builder and his crew out to Del Fuego to advise whether you should continue in your boat or charter the Antinov to fly your hull home for repairs? With due respect to Jeff, you only have to be in Aukland one or twice to see the reality of this situation, the quotes of $30K seem to be reasonable for insurance damage on some minor mooring incidents. The owners dont care, they fly home while the hull dries out. Something the designers of these laminates have not addressed regardless of kevlar or dyneema. This kind of disaster would destroy most peoples cruising plans, so steel under these circumstance makes logical sense. Its wrong of coarse for Jeff, this is just part of the game of hitech, you gotta have pain for gain Jeff?? Even if it is wrong on the Silicon Graphics workstation and finite element analysis version 23, steel users dont give a damm, something some people refuse to acknowledge. What i largely see is a low tech fleet of slow(relatively) heavy plastic, steel and ferro. Simply most cant afford the "ideal" boat, and even if they could afford it could not spare the time for long term cruising. I see time and time again the Techno Wizard boats on the milk run from San Diego finnishing in Aukland, and low and behold they fly home and get the crew to deliver the boat home. Not what most long term cruisers are thinking about, the horizon will always be there for them. Another fact is simply that the vast majority of yachts go nowhere, the more hitech the boat is the faster you will sail and probably you more likely to go nowhere. Very few of these boats are really thought out well let alone be designed by somebody who has actually cruised. This assumes most who build metal boats want to cruise. Most others will be stuck in the marina with the owners on the bar stool, saying see my miracle 99 overthere its built out of fritanium fudge and its the best thing since sliced bread, i bought it for cruising but my wife hates boats and prefers her friends at the country club or the Newport Yacht club. It seems only the affluent have the money to buy these boats, so presumably they wont have the time to cruise. It seems the vast majority of the hitech fleet fall into this category and simply have a arrogant diposition and laugh at people who happily cruise for years on 32 foot boats or anything that did not cost a million. Considering that a hitech trailer sailor will cost more than most steel boats, one wonders how logical it can be that small hitech uncapable boat costs more than the average steel do anything cruiser. My personal view is that those hitech junkies they have long lost the will to dream or be captured by romantic ideals. Unfortunately carbon fibre and fudgy cores dont figure in this the romantic lines of many cruisers dreams. I think most people who have practical common sense will look at steel or old heavy plastic, those that cant afford the classic plastic opt for building and most times its steel. Its totally wrong to call these people fools and shoot them down with unproven techno babble. Because simply at the end of the day anecdotal evidence is in their favour. Its amazing occurence if some el cheapo Beneteau which a kid can stick a screwdrive through does a circumnavigation, yet the numerous steel hulls from 26 and up rarely get a mention. It always amuses me that in the usa where most boats are plastic and the huge media bias against anything economical and under 40 feet i see sometimes more small cruisers and steel cruisers in most ports. Someone is certainly missing the boat. The bias towards production plastic boats and 44 foot plus is clearly evident. Yet outside this unreality the evidence is exactly opposite. So one really has to wonderS who is fooling who. I am sorry to say Jeff your reasoning is not part of common cruising folklore and dreams, you need to work on some romantic cruising story books featuring hitech, or start the Asmovian boat group where members can determine if its shorter too Tahiti through a black carbon fibre hole or whether the dynamics of H2O surface tension will get your there without fixing or finding wormholes in the laminate. SO what i am saying is that its nice being modern and technically aware, but the boat hull is only about 1% of the total pie, and to simply focus on the material when 99 other elements have to be considered is wrong. If building in steel saves you money, time and does the job who really cares about those other things. Just like most of us in our daily lives know the space program is good for us long term, we dont contemplate that the space shuttle tiles will be on our keel in the future. We roof our houses in clay and use lead in our keels. The sad fact is that regardless of how good these materials are, there are only probably less than 5 builders in the world who can do the kind of boats the Jeff advocates. Since this group is about people interested in building these kind of simple egalitarian boats, i thought i would focus on these ideals, and strengths of the philosophy of the designers and the people who dare to dream and dont play the consumer orientated childish snobbery games of life.The final comments is that there more web pages on steel boats and cruising than hitech laminates and hitech boats, that should tell you something. Will From: willyacht@y... Date: Mon May 28, 2001 2:38 pm Subject: Re: Determining costs for hull building I dont think metal is hard to quantify, its actually the best material to produce a cost and a time line. The most unfortunate thing about steel is that you charged for waste. But using the scrounging approach waste might be a minor consideration, since you will beg borrow or steal to fit!! Steel is a commodity that is very competitive and you really got to have unusual reasons for cost increases. My experience has been that most times i have been spot on in terms of hull structure, but been way off in the "unusual areas" like rudder bearing, plastics, stainless, and other hitech materials and paints etc, these products just seem to increase every few months. The rig and engine can be also be spot on. What is the hardest and is always way off is the boats interior. Sometimes i marvel at how quick and cheap the hull is on the excel spreadsheet, then just freak and say why is everything not made out of steel. Thats why my boat is aluminium, since i had the philosophy of welding in everything i could. I could blow up a cow in my boat and hose it down. Thats only something you can achieve in metal. Unfortunately no can do in steel because of weight. I will be watching with interest to see a Aluminium Swain Hull, because the potential for wash and wear is great. Will From: sunyataspirit@y... Date: Mon May 28, 2001 4:50 pm Subject: Aluminum Swain Hi Will, Great post on economics and home built/finished boats. There is an aluminum Swain hull under construction here in Nanaimo and when Alex has a chance to get down here hopefully he'll be able to get some pictures. Cheers, Richard From: winslow59@y... Date: Wed May 30, 2001 7:33 pm Subject: Any experience with or opinions about CCBB Has anyone here had a hull/deck built by Confidence Custom Boat Building (CCBB)? Quality of work? Cost? If not -- any opinions? http://www.boatbuilding.ws From: sunyataspirit@y... Date: Wed May 30, 2001 10:05 pm Subject: Re.CCBB I don't know much about them but their website seems to indicate some measure of experience. One item of note is that from what I have heard , and this is hearsay, they don't pay a residual to Brent for each boat built from his plans; whereas it is generally a condition of sale that only one boat may be built from a set of plans from a designer. If this is correct then I feel there may be a somewhat dubious lack of ethics at play here which may have the potential to extend itself to the construction process. Their prices seem somewhat high, no doubt due to the fact that there is overhead and a work crew to pay for. When a hull is pulled together by Brent, or Evan Schaler the overhead is minimal as they work on their own. I believe that having the hull built by either of the afore mentioned is very cost adventageous and the quality of work well known. Just my personal thoughts. Richard From: neilhuget@c... Date: Wed May 30, 2001 11:36 pm Subject: Re: [origamiboats] Any experience with or opinions about CCBB I assume you've seen Confidence's web site... Without the usual series of frames I'd be concerned about hull strength and that both sides were symmetrical. It's quick to build, but we aren't talking about a toy boat in a puddle here. Plus, the used Brent Swain boats I've seen for sale on the net are selling pretty cheap and I'm wondering why when they aren't very old and the interior seems as nicely done as much more expensive steel boats. From: brentswain38@h... Date: Thu May 31, 2001 12:37 am Subject: Re: Any experience with or opinions about CCBB Most of my boats sell for many times what their owners have invested in them .A well progammed product of the consumer society judges the value of everything by the price tag attatched, making him a sitting duck for a typical used car salesman.Most experienced offshore cruisers are more inclined to use their own logic rather than simply respond to such programming. Most people who have built and cruised extensively in my boats wouldn't even consider building anything else.Winston Bushnell sailed his first brentboat around the pacific , first to Hawaii, then through the Marshals, Carolines, Japan, Aeutians and back to BC. He sold her to build one of my 26 footers to sail through the NW passage.After that trip he sold that boat to build another 36 to do the circle pacific trip again, his third brentboat. Before this he had done a circumnavigation.His daughter is now building one of my 26 footers. Mike Ward is returning from New Zealand in his second brentboat and talking about building a third for a non stop circumnavigation. Jack Carson, having completed a circumnavigation on one of my 36 ft twinkeelers is on his second brentboat. The structural strength of my boats have been well proven in high speed collisions with everything from steel barges to icebergs to log booms to pounding on coral reefs, to 16 days pounding on a leeshore on the west coast of the Baja in 12 foot surf, to being dropped up to 15 feet to a single season passage through the northwest passage to several circumnavigations , all without transverse frames , and all without major structural dammage. I know of few other designs with such a proven track record . Measureing the distance between the hull -deck joint and the centreline, I've found my boats symetrical to within 1/16th of an inch , much better than most of the production fibreglass boats in existence. When something has been so well proven over a period of twenty years and over 100 boats, saying it won't work is about as intelligent as telling a returning astronaut as he's stepping out of the space shuttle " The world is flat, you know" If you hit a framed boat with a sledge hammer , the closer you hit it to a frame , the easier it is to damage it. Transverse frames have proven time and time again to be a structural liability, not an asset.It's much easier to punch a hole in a boat next to a transverse frame than in the middle of a plate. Brent Swain From: "Norm Facey" Date: Thu May 31, 2001 4:13 am Subject: Steel masts vs stability There's been recent exchange on steel masts, with some discussion on their positive stability effects if sealed (though this does mean that you're already far enough over to submerge the mast.....). I've seen other comments upon the earlier negatice stability effects of the extra weight aloft - have the steel mast proponents looked at that? Norm Facey From: "Alex & Kim Christie" Date: Thu May 31, 2001 6:29 am Subject: Re.CCBB royalties issue According to what Brent told me not long ago, the royalties issue has been resolved and relations are currently on the level with Confidence Boatbuilding. Alex Christie (moderator) From: willyacht@y... Date: Thu May 31, 2001 11:00 am Subject: Re: Steel masts vs stability All Weight above the waterline will affect stability. You boat needs a reasonable static stability figure in the first place before you will start to have a huge impact. Many of the protagnists in the stability debate seem to ignore totally the fact that most cruising boats will be overloaded with excess weight, roller furlers, radar towers etc. This overloading has a huge impact generally on a boat with an initially low figure. Studies have shown that a typical cruiser once equipped with a roller furling and other odds and sodds will have as much as 15 degrees less positive static stability. Getting back to the question, yes it does have a impact on stability only if its poor in the first place. Secondly if the boat has a good high range initially the positive range can increase by as much as fifteen degrees using a sealed mast. This positive effect can negate all the heavy overloading if you do get knocked down. Thirdly a boat with a heavy mast will increase a boats resistance to capsize, over the same boat with a lighter mast. A heavy taller object increases the boats roll inertia. Start off with a good design, good static stability and the effects of sealed mast and heavy roll inertia will come onto play making the boat seaworthy. But if you a go fast junkie you will want to tow the line and install a fried pretzel. Will From: burr.halpern@a... Date: Thu May 31, 2001 12:39 pm Subject: Steel masts vs stability at normal heel angles Actually, this business of using a steel mast has struck me as pretty strange as well. While it is true that carrying a sealed spar will help with inverted stability, the weight of that spar carried high up in the boat means that you are more likely to get that spar in the water. It is especially a problem in a boat that already carries a high center of gravity (due to such heavy items as a steel deck and topsides, chain anchor rodes carried on deck, moderately high cabin structure constructed in steel, etc,) Further exacerbating this issue is the fact that the boats are shoal draft, and use widely splayed bilge keels (resulting in the leeward keel remaining to leeward of the center of buoyancy until the boat reaches a reasonably high angle of heel (Eyeballed at 50-60 degrees) and the depth of the hull which lowers the center of gravity; all of that on a narrow wall-sided Hull, Unless the laws of physics has been suspended and I had not noticed, a high VCG in relationship to the center of gravity results in a boat that rolls though wider roll angles and is more prone to heeling. This high heel angle was confirmed in Brent's comments on his use of a wide splay angle on the bilge keels. Modern boats purposefully designed for offshore work, with the current trend in very low center of gravities, are designed to sail at heel angles less than 20 degrees with 10-15 degrees being more optimal. Bilge keels as shown on Armelle appear to be at an angle optomized for this more vertical sailing angle. There are a number of elements to a stability curve for any boat that are critical to a long range cruiser. The first is discussed a lot around here. That would be the range of positive stability which Brent estimates at a very high angle. The second is the magnitude of the positive stability at normal heel angles (In other words the amount of force that is required to heel a boat when it is within its normal sailing angles.) It is here that I really question the idea of doing anything (especially as extreme as using a steel mast or carrying a chain anchor rode on deck) that raises the center of gravity on the boat. As Will points out, a heavier or taller spar has a greater roll moment of inertia. This means a couple things, the boat will roll at a slower rate, but it will store more kinetic energy and so will be prone to rolling through a wider roll angle. This higher roll moment might reduce the likelihood of a knockdown due to excitation (rolling in situation where the frequency of the waves are at the same natural frequency of the boat) but in a situation where a boat is being rolled by a breaking wave, the more common and dangerous form of a boat being rolled over due to wave action, the inertia of the high center of gravity will carry the boat further through its roll and make it more likely that the boat will get its mast tip in the water. This is a critical element to the likelihood of a rollover because when a boat takes a major knock down it begins to slide to leeward on its topsides (its keel is no longer at an angle to the water to generate much lateral force) and so dipping a mast tip means that driving the mast and sails through the water which of course will greatly increase overturning force. (Been there, done that, got the teeshirt- Lucky to be here to tell the story) The affect on wide roll angles and large heel angles is that the boat is more prone to taking a major knockdown and the boat is also going to be harder on its crew. During the post Fastnet Studies the key issue cited over and over again, regarding the cause of sheer number of major knock downs, was high center of gravities relative to the center of buoyancy on the boats of that era. It is one of the key faults cited in Marchaj's seminal (but slightly dated) book on 'Seaworthiness'. While I know I am about to hear about the half dozen of these boats that have made major passages and circumnavigations, I still say, that proves nothing. Hunter Marine used to have a list of over a 100 circumnavigations performed in their boats and they have a guy who just finshed his second circum-navigation previously in a Hunter 37 and this time in a Hunter Passage 42. Supposedly he is about to order another Hunter. None of us would look at a Hunter (except perhaps the HC50) as a boat designed for offshore work. Respectfully Jeff From: pvanderw@o... Date: Thu May 31, 2001 2:00 pm Subject: Re: Steel masts vs stability at normal heel angles --- In origamiboats@y..., burr.halpern@a... wrote: > Actually, this business of using a steel mast has struck me as pretty strange as well. A couple of comments on different aspects of your post: 1) I thought that it was pretty clear from context that steel masts were only under consideration when the overall weight was similar to the weight of an aluminum mast. 2) The post-Fastnet analysis also concluded that the very light masts of ocean racers contributed to a low roll moment of intertia, and that boats with heavier masts were less likely to be rolled by a breaking sea. 3) Consideration of each bilge keel indiviually leads to error. To get a correct view, they must be consdered together. A little trig exercise will reveal that the projected area (plan view) of two bilge keels remains the same at all angles of heel: As the windward one becomes less effective, the leeward one becomes more so. With well- splayed keels, the windward keel will come out of the water earlier, causing an enourmous increase in righting moment. 4) The range of performance among heavy displacement sailing vessels of the same size is comparitively small, especially off the wind. 5) Note on B. Swains's earlier post: I think it is a legitimate point of view that the only reason to use frames in any construction is to be able to use thinner planking. Once the decision is made to use planking (plating in this case) heavy enough to stand, there is every reason to dispense with frames. If construction accuracy is a problem, then temporary forms can be used. Peter From: "Alex Christie" Date: Thu May 31, 2001 6:58 pm Subject: construction photos Dear Group, I have posted the URL for the complete construction sequence of the bare hull of Gene's Swain 36, into the groups's "bookmarks" section. The URL is http://members3.clubphoto.com/gene232990/Boat_Pix_2/ Alex Christie (moderator) From: "Alex & Kim Christie" Date: Thu May 31, 2001 9:58 pm Subject: Sail Tech yachts in Burnaby Here is an interesting thing to ponder: The following shows work done by Sail Tech yachts in Burnaby. I immediately recognized the photo of the first sailboat on the page as a Brent Swain hull, even though they indicate it as their own design on the web-page. Close examination of the bow roller shows it to be made exactly to Brent's plans as well. A phone call to Gunter at Sail Tech confirmed that the boat indeed is one of Brent's (I hope they paid him), but they have not since credited Brent as designer on their site. It is a 36, not a 39 as they claim. I do not know why they would say this. http://www.interchg.ubc.ca/konesky/sailtech.htm Sail-Tech home page: http://www.sailtechintl.com/s/Home.asp Their 47 footer is listed at $750,000. Although they are making good use of the ease and speed of the technique, and promote it as such, but it does not appear that they are passing the savings on to the customer.... It is a little ironic that they purport to be the originators of the technique, but I also note that they are selling stocks in their company, so are trying to create a strong public image for potential investors. Unfortunately knowing what I do about them, it has the opposite effect on me, and I would be highly reluctant to invest in a company that is not entirely honest. They should give credit where credit is due. My feelings are that they are putting out a good product, but are not entirely up-front about the origins of their design principle, but it is encouraging to see that the technique is being accepted. It is, furthermore, a tip of the hat to Brent from naval architect Grahame Shannon has seen fit to convert his Amazon 47 design to Brent's technique for Sail Tech so that it can be built more easily, yet not suffer loss of performance. Alex Christie (moderator) From: brentswain38@h... Date: Thu May 31, 2001 10:24 pm Subject: Re: construction photos In tests published in Cruising World, a model which would be rolled through 360 degrees by a given sized wave ,without a mast, would only be rolled 40 degrees with a mast in ,by the same size wave. By the time the mast is set in motion, the wave has passed, unless the mast is extremely light. This , it has been suggested ,is probably why boats often get rolled over the second time after losing their mast in the first rollover, a good reason for building the strongest possible mast.( ie steel) Boats sailing alongside one another with a much heavier 6 5/8th inch OD mast don't seem to sail at a noticably greater angle of heel than sisterships with a 5 1/2 inch OD mast, perhaps because only 20% of the heeling pressure is from the weight of the rig, and 80% is from the pressure on the sails. Twin keels , being shallower have much less of a tripping effect on the hull than a deeper keel. Their centre of lateral resistance is much higher, as they are much higher up the deadrise.Thus the whole hull is much more prone to get knocked sideways by a wave than it is to be tripped and capsized . Another weight saving consideration is the ability to weld tangs and other fittings directly to a steel mast with 100% strength, making them much simpler and thus saving weight in the proccess.The 100% strength is also a plus.Making the welds longer than the cross section of the tangs improves this guarantee. A 6 inch OD steel tube has roughly the same weight as a solid 6 inch diameter fir solid mast and roughly the same weight as a 5 1/2" by 8" box section with 1 1/4 inch walls, a common size for 36 footers a few years back. Tangs and fittings for a wooden mast would be much heavier, as they would be more complex. I was skeptical when my clients first began using steel masts, but they have been highly successful, and those who have used them say they would use nothing else. Brent Swain From: brentswain38@h... Date: Thu May 31, 2001 10:38 pm Subject: Re: Sail Tech yachts in Burnaby The boat in the picture looks like the one Ken Splett built for Fastwater Marine when they were in Richmond. If it is, I was paid for it. It was sold to Ian Leckie who is finishing it in Calgary. Gunter bought a set of drawings for the 36 and Ken scaled them up to 39 ft and Beneteau-ized the stern and pilothouse.He also increased the depth of the keels.I didn't have drawings for the 40 at the time. The 47 looks like one he built at Shelter Island in Richmond.He ran into serious distortion problems when he melted lead into the keels, a practise which works well for steel, but a disaster in aluminium. Building a mould for custom shaped ingots is a better idea. Ken recently built a couple of origami aluminium 53 footers where he built a steel mould for the ballast, melted it full of lead, then dropped the works into the aluminium keel and welded an aluminium airtight cap over it . That worked well. Brent Swain From: burr.halpern@a... Date: Fri Jun 1, 2001 2:20 am Subject: Re: Steel masts vs stability at normal heel angles Reply: I would agree that the moment of inertia and performance of a steel mast would be the same as an aluminum mast of equal weight, BUT, if the two masts were of equal weight then either the aluminum weight mast will be way stronger than would be required for the loads involved or the steel mast would be very undersized for the loads. In other words, A60 steel is three times heavier for a given cross section than Aluminum, but only 1.5 times stronger than aluminum. (Of course the equation gets worse if A36 steel (common cold rolled structural steel) is used.) Beyond that, given the long panel lengths and the typical combination of bending and axial loads found in a typcial rig, the sectional properties will often govern such that in reality a steel mast may end up being over twice as heavy as an equal strength aluminum mast. Reply: Actually the studies after the Fastnet disaster concluded that a high roll moment of inertia was beneficial in the single 'rogue wave' circumstance. While it is true that a heavy spar is one way to increase roll moment of inertia, increasing the moment of inertia by raising the center of gravity carries a stiff penalty with it. A better solution from the standpoint of comfort a sea, as well as stability, and safety is using a bulb keel which increases the moment of inertia and also lowers the center of gravity at the same time. This lower center of gravity permits more sail to be carried comfortably which provides a benefit in both light air and heavy. Reply: Actually you are right here. Assuming that you had two boats with the same weight and same center of gravity, it does not matter whether the keels have a wide or narrow splay angle. That said, the apparent weight of a bilge keel clearing the water will go up by 64 or so pounds per cubic foot so because it no longer has the buoyancy of the water helping to float it. > > 4) The range of performance among heavy displacement sailing vessels > of the same size is comparitively small, especially off the wind. Reply: I really think that this one is dead wrong. I can perhaps illustrate this with an example. First lets talk about two boats of the same exact weight. One has a heavy hull, deck, rig and a very heavy interior. It is traditional in appearance with comparatively long ends. It has a low aspect ratio keel with a lot of surface area and uses a low density ballast which because of its bulk is carried comparatively high relative to its center of buoyancy and results in a keel with a lot of camber. Now, compare that to a boat with a light hull, deck and interior. Its equal weight comes from larger tankage and storage carried low in the boat, much of this weight below the water line. It has a long water line which permits finer sections and a shallower canoe body. This permits a longer span on the keel and permits less wetted surface for the same amount of lift. This boat uses a hollow keel foil as one of its water tanks and has a high density bulb keel of equal weight to the ballast in the first boat. This boat would have a substanially lower center of gravity and could carry a taller and more powerful rig, and more over could carry more sail in a building breeze. It would also roll through a smaller angle and at a slower roll rate. So, I would think that the second boat would be faster on all points of sail but especially so on a reach where its longer waterline length makes a real difference in hull speed and its lower drag would really have an effect since the boat would spend more time at or near hullspeed. Probably the most graghic example that I am aware of is the case of a Brewer 12.8 and a Whitby 42 coming up the Atlantic two years ago. The Brewer uses the same hull as the Whitby but the Brewer has cored decks and topsides. Both boats weigh the same but the weight savings on the Brewer from the coring is used for additional ballast. The Whitby has a full keel while the Brewer has a cut away forefoot and cutaway behind the keel and in front of the skeg hung rudder reducing wetted surface and permitting a more efficient foil shape. The greater stability from the heavier keel allows the Brewer to carry a cutter rig while the Whitby's are a ketch. Coming up the Atlantic a few years back, both boats left Miami at the same time but the Brewer made it to Beaufort in under 5 days compared to the Whitby's over 6 days and the Brewer has substanially fewer engine hours. I know that this is too small a sample to be a terribly scientific representation but you can easily visualize that boats of equal weight will not have equal comfort, speed, or seakeeping depending on how the hulls are modeled, the weight is distributed, and the keel and rig employed. > 5) Note on B. Swains's earlier post: I think it is a legitimate point > of view that the only reason to use frames in any construction is to > be able to use thinner planking. Reply: While I understand Brent's prejudice against transverse frames that touch the plating, I still believe that transverse frames play an important role in distributing large lateral loads such as those that would be encountered when the keel strikes bottom in a boat being drive ashore beam to. There is a very localized bending moment that in the absense of floor framing (transverse frames through the bilge area is imparting an enormous concentrated load perpendicular to the skin. From: pvanderw@o... Date: Fri Jun 1, 2001 2:17 pm Subject: Re: Steel masts vs stability at normal heel angles Comment (not rebuttal): > Reply: Actually the studies after the Fastnet disaster concluded that a high roll moment of inertia was beneficial in the single 'rogue wave' circumstance. Yes, they were talking about a single wave. I think that 'breaking crest' is probably a better term than 'rogue wave.' It seems to me that many rogue waves are blamed for too many accidents, and seems to imply that the accident was due to bad luck. The 'rogue' was just a wave that caught them wrong. > Reply: I really think that this one is dead wrong. I can perhaps > illustrate this with an example. First lets talk about two boats of > the same exact weight. I concede the point, but I have to say that in describing the two boats you have exagerated their dissimularity. By making them the same weight but different waterlines, you have given them different length/disp ratios, while I was thinking of equality. Peter From: "Alex & Kim Christie" Date: Fri Jun 1, 2001 5:21 pm Subject: loads on keel striking bottom Jeff wrote: > Reply: While I understand Brent's prejudice against transverse frames > that touch the plating, I still believe that transverse frames play an > important role in distributing large lateral loads such as those that > would be encountered when the keel strikes bottom in a boat being > drive ashore beam to. On Brent's boats, I think the high deadrise of the hull bottom midships would adequately handle the load imparted form an impact on the bottom of the fin keel. It is very difficult to push in the point of a triangle, and the hull bottom has similar geometry, with the keel essentially put on to the point of a shallow triangle. Brent explained it quite well to me yesterday, and maybe he'll step in and give a better illustration/ explanation than I have here. From what I saw on Paul Liebenberg's boat, the twin keel version has substantial transverse webs running across the tops of each keel to spread the lateral and perpendicular point loads imparted to the skin. It would be of interest to see what Grahame Shannon did in his Swain-style version of the Amazon 47 in aluminum. The hull midships looks to be more of a shallow arch, and there surely must be some sort of web in there to take up loads, or else it may be vulnerable to the problems Jeff expressed concern about. The 47 foot hull on the Sail Tech website www.sailtechintl.com shows a fin keel. Alex Christie (moderator) From: brentswain38@h... Date: Sat Jun 2, 2001 9:27 pm Subject: Re: loads on keel striking bottom One of my boats spent 16 days punding on a lee shore in 12 foot surf before being dragged through the surf, being picked up and dropped 12 feet every wave for 1/4 mile, with no serious dammage. Another 36 hit the reef leaving Suva and pounded 300 feet accross the coral reef before being dragged back accross the reef by a tug ,to deep water. The only dammage was a crack in the wood mast and a small dent in the keel. Both were single keels. My twin keeler hit a rock at 5 knots with both keels.The boat went from 5 knots to zero , instantly ,and I went through the open hatch. One of the trailing edges of the keels was driven in a couple of inches and had to be jacked down with a hydraulic jack. I've since welded a floor across the webs to triangulate the webs ,which will completely prevent this in the future. On new boats, I triangulate the centreline by making the entire centreline into a tank, with the back of the tank where the trailing edge of the keels meet the hull.I've done this with Paul's boat too. This would make it impossible to drive the keels up into the hull. It also makes use of a hard to use space, and , with a 12 by 24 inch inspection plate and a plexiglass window , makes it easy to access and inspect or work on the tank at any time. On the issue of knockdowns, one of the things which have proven to reduce the likelyhood of a knockdown is an increase in inertia( Weight ) of the vessel. Perhaps Jeff would have had less of a knockdown if he'd been in a heavier boat.How did your hatches fare ? did they keep the water out as a metal hatch would have ? Did you suffer any structural damage? Even in a light boat, Metal ( aluminium) is the best hatch material available. It can even make a boat very difficult for thieves to get into, unless the windows are too large. Brent Swain From: "Gary H. Lucas" Date: Sat Jun 2, 2001 10:46 pm Subject: 36' Building pictures I took a look at the pictures of the guy building the 36' boat, and the site where they are building in aluminum using the origami method. The pictures of the guy building the 36' boat was real eye opener. It looked like he pulled off the side of the road in a clearing where some pieces of logs were available and started building this boat! So much for a level site, an accurate jig for holding all the frames, heavy equipment for handling plates etc. that one would think are basic requirements! Yet the results look very good, and very fast. The company using the Origami method to build aluminum boats looks like they have taken Brent's concept a little farther, by developing software to calculate the shapes of the sheets and produce CNC files to do the cutting. Is Brent able to develop different hull shapes using equations or a CAD system, or is the shape of the panels derived empirically? I am in the process of refurbishing an old Catalina 22. As I do this and read about Origami boats I keep thinking, for the man hours I have in an old boat that will still be an old boat when I am done I could build a new one! I have all the skills, Machining both manual and CNC, Welding with Mig, Tig, or Stick on most metals, Cad design of machinery, Control panel wiring, Rigging and Millwrighting. Now all I have to do is convince myself to do it. Gary H. Lucas From: "Alex & Kim Christie" Date: Sun Jun 3, 2001 5:06 am Subject: New folder uploaded to Origamiboats A folder of Winston Bushnell's Dove III has been uploaded to the files section for your interest. This is the Swain 26 (Centreboard and stub keel) boat which transited the Northwest Passage from west to east. Images are from the boat listed at www.harbouryachtsales.com Alex Christie From: "Gary H. Lucas" Date: Sun Jun 3, 2001 2:40 pm Subject: Question about Origami method Brent, I am trying to understand how the metal deforms when bending up a hull. It seems to me that the steel remains as a developable shape as it is bent. That is, it only bends in one direction at any point, it's not a compound bend. Is this correct? Assuming this is correct, does this imply that one could lay a straight edge on the hull at every point along its length and find a straight line where it will touch, except where the joints are? I am trying to get my mind around the whole concept of what the final shape looks like. I'd like to see if I could model a shape like this in Rhino, a 3D surface program. If I could then the program can generate hull volume, center of buoyancy, center of mass, etc. which would be interesting to play with. Gary H. Lucas From: turpin@y... Date: Sun Jun 3, 2001 3:08 pm Subject: What tools does Rhino 3D have to model simply curved surfaces? --- In origamiboats@y..., "Gary H. Lucas" wrote: > That is, it only bends in one direction at any point, > it's not a compound bend. Is this correct? .. A topologically flat surface stays topologically flat (no compound curves), unless you somehow stretch the material. That's mathematics. As to the practice, Brent should say. (But I would be surprised if the cutting and bending used to build origami boats stretches the steel.) > I'd like to see if I could model a shape like this in > Rhino, a 3D surface program. .. I played with early versions of Rhino, and found it fairly complex. Are the later versions more intuitive? Does it include a tool that fills in a flat surface between two single-dimensioned curves? If so, you can model an origami hull shape by drawing the sheer, the midline, and the joint, and then this tool should fill in the hull. What would be more interesting is if it includes the means then to go backwards, unrolling the hull into a flat surface, showing how it needs to be cut to create the resulting shape! Then you could model all sorts of things, and unroll them to get the cuts. Russell From: "Alex & Kim Christie" Date: Sun Jun 3, 2001 4:35 pm Subject: Re: [origamiboats] Question about Origami method Hi Gary, and welcome to the group. There may be a delay in Brent answering your question, as he has to get to a public terminal, so hang in there for a day, and a response will be forthcoming. At least 100 of his boats have been built, a good portion by him; I'm sure he'll have a good answer for you! I found that making the model from the pattern as printed in his guidebook was an eye-opener for me. Because the paper is also a sheet material, it seems to act more or less in the same way as the steel would (though I guess paper is not ductile). There is software from europe which is not for boats specifically, but could be applied in such a manner. It is an "unwrapping" program that allows you to take any object and unwrap it into a flat surface. I believe it has been employed to design packaging such as cardboard boxes, but it could be applied to many other things too. I'll see if I can dig up the name of that software. I don't know, being unfamiliar with programs, but maybe this is something that can be done as part of CAD already? It sounds like with all your metal working skills you've got the "right stuff". You'd be a shoe-in for this kind of boatbiulding. Alex Christie From: burr.halpern@a... Date: Sun Jun 3, 2001 7:14 pm Subject: Re: loads on keel striking bottom This is begining to make a lot more sense. Originally, these boats were described as "frameless" and I reacted rather negatively since from an engineering stand point you need a lot more than 3/16 plate on an over 10,000 lb vessel to achieve adequate strength without any frames. As this discussion has been progressing it has been pointed out that these boats are not really frameless. They have longitudinal framing and the have transverse floor framing in the area of the keel. These are beginning to sound like a normally framed light steel boat. Add a couple knees or transverse frames at the shrouds, stem, and backstay and a strong back at the keel and engine beds and you have a normally framed small steel boat. We can all tell our tales of being on a boats that hit hard and survived. My own 28 footer (which I would best describe as a very light weight, but well engineered, coastal cruiser/racer) struck bottom at just under 8 knots and while some of the energy was dissipated by the boat jumping vertically, the keel had absorbed the energy of slowing a boat by 6-7 knots. When we hauled out for the season we found virtually no damage except a slight mushrooming of the lead keel tip which we beat back with a metal workers hammer and refaired. Of course, the impact load in stopping a 4100 lb boat is a very small fraction of the impact in stopping a stopping a heavy weight cruiser. Brent suggested that "Perhaps Jeff would have had less of a knockdown if he'd been in a heavier boat." and asked "How did your hatches fare? Did they keep the water out as a metal hatch would have ? Did you suffer any structural dammage?" To answer Brent's question, while I have been through a lot of knock downs in small day racers, the knock down in question actually did occur on a heavy cruisng boat. We might have actually faired better in a lighter boat with a higher righting moment and lower center of gravity. With the light boats that I have knocked down on, there is a point at which the boat actually slides sidewards on its topsides. The boat that I was refering to in my post and that Brent was asking about was a heavy cruiser with a very heavy aluminum spar. That boat was rolled to an angle well past 90 degrees, and far enough to get the mast tip in the water. The forward hatch was in the water and sustained a fair amount of pressure as the boat bottomed out in the trough of the waves. There was no damage to the hatches that I could tell and the forward hatches did not take water. The main companionway hatch, (a fiberglass sliding hatch with teak hatch slides) was not in the water as best as I can speculate (its not where my eyes were focused) and it did not take green water nor was it damaged. Once the mast tip was in the water our sidewards motion seemed to slow and the boat jerked over what I would estimate to be probably an additional 15-20 degrees as we hit the trough and the mast drove into the back of the next wave. I was left hanging from the boom vang with my legs clear of the deck. On that boat we suffered some sail damage, some gear like winch handles going over the side, and a bent stanchion. There may have been more damage but at this point in time I can't recall anything else specifically. Several of the crew were pretty banged up by flying gear or being tossed during the last piece of the snap roll. On my own boat, I experienced the phenomina of taking a knock down and sliding on our topsides in winds over 65 knots (A nearby boat pegged their anemometer at 65kts. We under a double reefed mainsail and were not flying a jib. My boat knocked down to what I have always estimated as approximately 60 to 70 degrees of heel. At that angle of heel the boat was sliding sidewards on her topsides. The waterline was about even with the inside of the coamings and the cabin sides were in the water. There were occasional rooster tails off of the winches on the cabin top. The forward hatch and companionway were not in the water (in fact the companionway did not have the top slide in place but we took no solid water down below). The spreaders were not in the water but were quite close at different points in the wave train. When I was able to get to the mainsheet (which was underwater) and release it, the boat stood up enough (probably to 30 degrees of heel so that the keel and rudder were in the water and I could feather up and steer. From that point on we were able to maintain something less than a 30 degree heel angle by a combination of sail trim and steering corrections. This was by no means easy. Obviously, had this storm lasted more than a half hour at these windspeeds (it dropeed pretty quickly into the 20's), it would have worn out our crew of two to the point of being dangerous. Then again this was on a 4100 lb 28 footer that was not really intended for that kind of high wind conditions. In terms of damage, we lost the upper batten out of the mainsail but otherwise the boat was none the worse for wear. We were the only boat around us that was able to beat clear of the River mouth and several large cruising boats were beached when they could not make to weather (or put their bow through the wind) against the conditions. In that same storm a 30,000 lb, 44 foot heavy cruiser (that we had been cruising with) took a knock down to what we estimate to be pretty much the same angle of heel (60-70 degrees) as we sustained but they were under bare poles. The only damage that I recall is that she had minor damage to her soft dodger. Jeff From: pvanderw@o... Date: Sun Jun 3, 2001 8:49 pm Subject: Re: What tools does Rhino 3D have to model simply curved surfaces? > A topologically flat surface stays topologically flat > (no compound curves), unless you somehow stretch the > material. That's mathematics. As to the practice, > Brent should say. (But I would be surprised if the > cutting and bending used to build origami boats > stretches the steel.) Because steel, like most materials, is stronger in compression than in tension, a sheet of steel will not always bend into the theoretical ruled surface. The designer Weston Farmer described using this phenomenon to get a more nearly round-bilged hull for his Taihitana design. I repeat here only what I have read; I have no independent or engineering knowledge of this phenomenon. Peter From: burr.halpern@a... Date: Sun Jun 3, 2001 9:05 pm Subject: Re: Question about Origami method While it is posible to form steel into compound curves (look at most any automobile) the tools required are beyond those available to most amatuer boat builders. Most steel boats are built with conic sections (sections that can be derived from a cone shaped object) with the panels curved into developable shapes. You are correct in assuming that at any point in the hull (except the chine)you should be able find an orientation at which a straight edge would lie flat against the hull. Obviously these lines of orientation are neither vertical or horizontal. Jeff From: turpin@y... Date: Sun Jun 3, 2001 10:01 pm Subject: Doh! (was: What tools does Rhino 3D have ..?) --- In origamiboats@y..., turpin@y... wrote: > Does it include a tool that fills in a flat surface > between two single-dimensioned curves? .. Thinking about this, a few minutes after I posted, I realized that the topologically flat sweep between two curves is not unique. In most cases, there is an infinite number of simply-curved surfaces that can be fit. If you're still following this, with the image of a line segment sweeping along both boundaries, the variation depends on the relative speed its end points move along them. It's no longer obvious to me how a CAD program would let you model the folded shape, beyond specifying the flat cut-out, and letting you identify the joints that are glued together. Russell From: "Alex & Kim Christie" Date: Mon Jun 4, 2001 6:32 am Subject: tortured plywood, origami-style solo canoe Just found this site from Duckworks magazine, which has a link for a tortured plywood solo canoe. The patterning is sort of similar to the Brent Swain style for the steel boats, except that in this case the "tabs" or tongues which are pulled together are in the top strake zone, whereas on Brent's boats they are on the bottom. For a small punt, it would be easy enough to get the sides fair. On a 36 or 40 foot boat, it'd be better to leave the top panel unbroken in order to achieve easy fairness. Brent's aluminum dinghy design, shown in the files section, uses the tabs on the bottom, like his larger boats. Alex Christie From: "Alex & Kim Christie" Date: Mon Jun 4, 2001 6:36 am Subject: ...and here is that site (oops) to err is human... Here is, at last, the URL for the folded ply solo canoe: http://www.duckworksmagazine.com/articles/swampyankee/index.htm Alex Christie From: pvanderw@o... Date: Mon Jun 4, 2001 4:01 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) > Thinking about this, a few minutes after I posted, I > realized that the topologically flat sweep between two > curves is not unique. More thought may be required, because Mother Nature is imposing more restrictions than you are considering. It is not enough that the surface of the sheet have non-crossing straight lines from one curve to the other, but that any two points must be the same distance apart (measured along the surface) on the bent sheet as on the flat sheet. With this added restriction, there will be, in general, no surfaces that meet the criteria. For particular curves, there will be one surface. This answers the question of how software unwraps the surface: by dividing the surface into small triangles, then laying the triangles out on the flat. Peter pvanderw@o... Wed 6/6/2001 From: turpin@y... Date: Mon Jun 4, 2001 6:53 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) --- In origamiboats@y..., pvanderw@o... wrote: > More thought may be required, because Mother Nature is > imposing more restrictions than you are considering. It > is not enough that the surface of the sheet have > non-crossing straight lines from one curve to the other, > but that any two points must be the same distance > apart (measured along the surface) on the bent sheet > as on the flat sheet. .. IF the modeled surface has no compound curves THEN it can be unfolded (unrolled) onto a flat sheet isometrically, i.e., in a fashion that preserves distance. This may require a cut (think of a cone). And in some cases, the unfolding may result in overlap that can't come from a single sheet of steel. > With this added restriction, there will be, in general, > no surfaces that meet the criteria. .. I think you're wrong here. Or misunderstanding the idea. Remember: the modeled surface is topologically flat, by virtue of being swept out by a line. Russell From: pvanderw@o... Date: Mon Jun 4, 2001 7:44 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) > I think you're wrong here. Or misunderstanding the idea. > Remember: the modeled surface is topologically flat, by > virtue of being swept out by a line. It is possible to create a compound curve by sweeping with a line. In fact, it is possible to create a saddle point surface (concave down on the x-axis, concave up on the y-axis) with a ruled surface. PHV From: turpin@y... Date: Mon Jun 4, 2001 8:26 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) --- In origamiboats@y..., pvanderw@o... wrote: > It is possible to create a compound curve by sweeping > with a line. .. This raises the question: What do you mean by "sweep"? Take any smooth 2d surface. If there is a part of the surface where you can lay a straight edge so that the edge contacts the surface for an interval, then the surface is simply curved at the points along that interval. Or to put it another way, if you put a straight edge against the surface at any point of compound curvature, positive or negative, it will meet the surface *only* at that point. The way I was using "sweep," the modeled surface is a set of straight line segments, each between two points on the boundary. Russell From: pvanderw@o... Date: Mon Jun 4, 2001 9:29 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) > The way I was using "sweep," the modeled surface is > a set of straight line segments, each between two > points on the boundary. Here is a web page with drawings of a number of "ruled surfaces," including a saddle point (Example 1) http://www.cs.mtu.edu/~shene/COURSES/cs3621/LAB/surface/ruled.html Example 3 shows a shape made by sweeping a straight line between two circles. A steel sheet can not be bent into this shape. Example 4 shows a shape made by sweeping a line between two arches, on inverted from the other. The curves do not have to be this different for the shape to become non-developed. For example, if a chine line becomes straight near the bow and the deck line is very full, the shape will probably be hard or impossible to build with sheet material. Peter From: turpin@y... Date: Mon Jun 4, 2001 10:19 pm Subject: Re: Double doh! (was: What tools does Rhino 3D have ..?) You're right. I need to rethink my reasoning. Russell From: burr.halpern@a... Date: Mon Jun 4, 2001 11:37 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) Actually, I think that you are discribing what in math terms is called a 'hyperbolic paraboloid'. A hyperbolic paraboloid does not produce a compound curved surface but is a developable surface, again made up of conic sections and which can be described by a series of straight lines. As such, a hyperbolic paraboloid can be produced in sheet metal and is the basis of any boat fabricated from dimensionally stable sheet materials with the possible exception of "tortured plywood" which is the precurser to almost all folded or 'origami' type construction techniques. Jeff From: "Gary H. Lucas" Date: Tue Jun 5, 2001 1:07 am Subject: Re: [origamiboats] What tools does Rhino 3D have to model simply curved surfaces? I tried several 3d programs a few years ago to see if they would be useful to me. I spent a few days with several different packages and found that after a few days I could not model many of the parts I needed to create a machine we were building, the learning curve was too steep. I got the demo version of Rhino and by the end of the second day I had enough of the machine built that looked pretty complete unless you zoomed in close for all the details. So I consider Rhino to be very easy to use. The current shipping version is 1.1, which is what you get if you download the demo. However all the people who really use Rhino day to day are running version 2 Beta copies. Rhino's betas are more reliable than most software in their regular releases! Version 2 has quite a bit of hydrodynamic functions and there are a number of boat designers using it. It does calculations like buoyancy, center of buoyancy, volume etc. There are lots and lots of ways to create surfaces! Rhino is the tool many people fall back on when packages like Solidworks, and Pro E have trouble with complex surfaces. Rhino can also unroll developable surfaces into a flat pattern now, but not with the demo version. I believe if I can figure out how to create the hull shape Rhino will give me a flat pattern. It is possible that something as simple as a 2 rail sweep with a straight line will produce much of the hull shape. Rhino lists for $795 but you can find it for as low as $425. The demo version is a full package, nothing is disabled but you only get to run it for 25 sessions, and you can't leave it on over night to save sessions. I highly recommend you try it if this sort of thing interests you. Gary H. Lucas From: cdbarry@h... Date: Tue Jun 5, 2001 3:05 am Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) A developable has to have zero Guassian curvature. This means that two adjacent rulings have to be co-planar, or that the cross product of the cross product of the ruling and the tangent to the chine at one end and the cross pruct of the ruling and the other tangent is zero. From: pvanderw@o... Date: Tue Jun 5, 2001 1:48 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) > Actually, I think that you are discribing what in math terms is called a 'hyperbolic paraboloid'. A hyperbolic paraboloid does not produce a compound curved surface but is a developable surface, again made up of conic sections and which can be described by a series of straight lines. As such, a hyperbolic paraboloid can be produced in sheet metal. Portions of the 'hyperbolic paraboloid' surface can be developed, but the saddle point (where the ruling lines cross) can not, as can be seen in a instant in the diagram. The other hyperboloids pictured illustrate that not all 'sweeps' can be developed. http://www.cs.mtu.edu/~shene/COURSES/cs3621/LAB/surface/ruled.html Peter From: halgordon@e... Date: Tue Jun 5, 2001 8:56 pm Subject: Michael Kasten's designs Has anyone built The Cutter, Bedouin? Or the Mini Kat? From: "Alex & Kim Christie" Date: Tue Jun 5, 2001 10:30 pm Subject: Re: [origamiboats] Michael Kasten's designs I have been waiting for a week for a reply from Kasten as to which of his designs have been built, but have so far not heard back. His last e-mail suggested I buy one of his study plans. Alex Christie From: brentswain38@h... Date: Wed Jun 6, 2001 12:13 am Subject: Re: Question about Origami method In theory the hull bends in one direction only, but in practise the shrinkage from the cutting torch and welding shrinks the edges of the plate, leaving about an inch of compound curve between the deck and the chine.This contributes greatly to the fairness and stiffness of the topsides.This is far less in the case of a hull cut with plasma with it's reduced shrinkage. In the bow, the stiffness of the hull plate results in a slight hollow in the foreward waterlines. I don't have the plates in Cad cam yet, but hope to in the future. Brent Swain From: brentswain38@h... Date: Wed Jun 6, 2001 12:19 am Subject: Re: What tools does Rhino 3D have to model simply curved surfaces? Alex is scanning the plate shape which should answer a lot of these questions. You can build a rugged model by cutting the pattern out of a flat sheet of fibreglass( one layer of matt wetted out, available from most plastic shops) , pulling it into a hull shape and fibreglassing the inside after pulling the beam into the proper shape.This is easier if the model is fairly large. Brent Swain From: cdbarry@h... Date: Wed Jun 6, 2001 2:06 pm Subject: Re: Doh! (was: What tools does Rhino 3D have ..?) --- In origamiboats@y..., pvanderw@o... wrote: > > Actually, I think that you are discribing what in math terms is > called a 'hyperbolic paraboloid'. A hyberbolic paraboloid is a ruled surface, but is not developable. Developable surfaces must be ruled, but not all ruled surfaces are developable. In fact, between any two chines there exists an infinite number of ruled surfaces but at most one is developable. The hyperbolic paraboloid has one principal curvature that is the circle perpendicular to the axis and the other the hyperboloid in the axis plane. One is positive, the other negative and their Guassian curvature (the product of the two principals) is negative, not zero. To be developable the rulings have to be a principal curvature. From: pvanderw@o... Date: Wed Jun 6, 2001 3:13 pm Subject: Re: hyberbolic paraboloids & ruled surfaces > A hyberbolic paraboloid is a ruled surface, but is not developable. > Developable surfaces must be ruled, but not all ruled surfaces are > developable. Yes. When I said otherwise in post 187, I was reacting off the cuff to post 184, and I realized that I had made a mistake just about as soon as I hit the send button. Anyone who tries to induce a saddle shape in a piece of paper will see that the hyberboic paraboloid shown at the link is not developable. Peter From: peter kittel Date: Wed Jun 6, 2001 10:59 pm Subject: Re: [origamiboats] Re: What tools does Rhino 3D have to model simply curved surfaces? Hello Alex,.. this is peter kittel whalesandsails@y... when I joined you guys I just wanted to look in on the discussion , perhaps participate, occasionally, at my own speed. - NOT get swamped by e-mail daily that I don't recall asking for. Would you stop it please! and no hard feelings, okay..? Do you know a Brent Swain boat(32' feet ?) called 'Sarsaparilla'? I wonder what happened to them, i met them 11 years ago in Costa Rica, I liked both of them, and was impressed by their boat, hence my interest now. Question: Would it be possible to cut one of your boats at the widest beam (later on) and insert a piece to lengthen it , meaning: do all hull lines , apart from the keel allow this? If you want to know what I did since meeting Sarsap. try: www.juprowa.com/kittel , please pass them my numbers if you are in touch with them. thanks! peter From: "David Hilliar" Date: Thu Jun 7, 2001 12:17 pm Subject: Michael Kasten Hi all I have just recently recieved an email from Michael. He is/has been on holiday but has returned my email. I too would be interested in hearing about his designs, They apeal to me with their traditional design and looks. David From: "Gary H. Lucas" Date: Thu Jun 7, 2001 1:16 pm Subject: Got It! All this talk of hyperbolic paraboloids makes my head spin! I have always been very good at visualizing 3D objects from 2D and so forth, but I am very weak in the advanced math department. I printed out the hi-res pictures of the posted 36' boat under construction and have been looking at those pictures every so often trying to my mind wrapped around those curves. Last night I cut out a paper version by eyeball and folded it up. I also played a little in Rhino to see how I might construct a hull like this. It finally hit me and it is SO simple! Here's how it works. The hull is made up ENTIRELY of CONIC sections, straight lines ruled on the surface all come to a common point. The first conic section is the center portion of side from the point on one side of the T shaped cutout to the other. The sides of the hull at the center only taper inward a few degrees, so this conic section has its center point WAY below the bottom of the hull, say 100 feet on a 36' hull. The second conic section is at the bow. Its CENTER is at the point of the T cutout and it sweeps from the start of the first section around to a point near the bottom of the T cutout. A third conic section is formed from the edge of the second and the weld line, and it sweeps along the bottom of the first conic section where the hard chine is. The stern works in similar fashion. What makes this so difficult to visualize is that the conic sections may not have a constant radius, and there are only two curved edges, visible the rail at the top of the first section, and the hard chine line at the top of the third conic section. The other edges are all irregular because they meet the rail at an angle or they meet the centerline of the boat. What this all means to me is that the hull can EASILY be modeled in a 3D program, and that Rhino in particular can unwrap this thing to a flat pattern with no problem! The only distortion you should get is from the welding, which Brent indicated is minimal, and at the center point of the second conic section which is located at the top point of the T cutout. It appears that making a circular cutout at the center point would greatly reduce distortion and the amount of effort needed to pull the plates into alignment. A small disk of material, possibly pounded in a somewhat hemispherical shape could then be used to plug the round hole smoothly. I hope to make a 3D model and unfold it over the next few days. If I am success I will post some pictures of the result. Gary H. Lucas From: brentswain38@h... Date: Thu Jun 7, 2001 11:23 pm Subject: Re: Got It! If the two top corners at the top of the T total 180 degrees, there should be no distortion there ,and there hasn't been any problem there. If there is, it can easily be fine tuned out after the rest of the boat has been pulled together. Brent Swain From: "Alex & Kim Christie" Date: Fri Jun 8, 2001 2:02 am Subject: swain hull model Dear Group, I have attached a GIF of the example model that Brent has mentioned that you can cut out to illustrate the process of building one of these hulls. I have it in JPEG format too, and will post this to the group files later on. I have tried to format both to print out to about 8 by 10 inches, suitable for printing. Let me know how it works out -- my printer is broken. Alex Christie Re: swain hull model Alex & Kim Christie Fri 6/8/2001 From: "Michael Casling" Date: Fri Jun 8, 2001 6:21 am Subject: Re: [origamiboats] swain hull model I think I have just successfully built my first boat. But I need a deck. Michael Casling. Tanzer 8.5m owner. This is my first posting to the group. caslingm@silk.net From: "Gary H. Lucas" Date: Fri Jun 8, 2001 11:46 am Subject: Modified Swain drawing I scanned the drawing Alex sent and added lines showing how I perceive the conic sections that show how the metal bends. Hope I got this right. Sorry the file is so much bigger, are there different GIF formats? Gary H. Lucas From: "Gary H. Lucas" Date: Fri Jun 8, 2001 12:44 pm Subject: No attachment I see attachments don't work. Alex, do files get sent to you for posting? Gary H. Lucas From: "Alex & Kim Christie" Date: Fri Jun 8, 2001 4:02 pm Subject: Re: [origamiboats] swain hull model >I think I have just successfully built my first boat. But I need a deck. >Michael Casling. Tanzer 8.5m owner. This is my first posting to the group. >caslingm@s... Michael:Congratulations on building your first boat, and welcome to the group! Alex Christie From: "Alex & Kim Christie" Date: Fri Jun 8, 2001 4:08 pm Subject: Re: [origamiboats] Modified Swain drawing Maybe Yahoo puts a limit on the size of file that can be scanned. Try saving as a JPEG instead. Alex Christie From: "Gary H. Lucas" Date: Sat Jun 9, 2001 1:32 am Subject: Modified Swain Drawing Here is a modified version of the drawing showing conic section bend lines Attachment Modifyedswain.jpg Type: image/jpeg Size: 65k Download From: "Alex & Kim Christie" Date: Sat Jun 9, 2001 6:51 am Subject: Re: [origamiboats] Modified Swain Drawing Thanks Gary, I'll add it to the files for those who are interested. I hadn't thought much about the geometry of how the sheet material behaves, but the lot of you really hashed it over very nicely. Good work! Knowledge of this sort, especially when tied in with a good CAD program, should make it much easier to adapt the technique to a wide range of hulls. Brent has already worked out a dinghy, but it would be further interesting to work out something for a utility skiff. Playing around with cardboard works too, of course...call it the poor-man's computer. I like how it never crashes, unlike my windows-based computer... Alex Christie From: cdbarry@h... Date: Mon Jun 11, 2001 2:32 am Subject: Re: Steel masts vs stability at normal heel angles > a steel mast would be the same as an aluminum mast of equal weight, > BUT, if the two masts were of equal weight then either the aluminum > weight mast will be way stronger than would be required for the loads > involved or the steel mast would be very undersized for the loads. A stayed mast is a slender column and controlled by Euler buckling, not yield. Young's modulus and section properties control Euler buckling and the ratio of Young's modulus to weight for steel is a bit higher than aluminum. In theory then a stayed steel mast would be few percent lighter than an aluminum one for the same external size. Your point about section properties is valid though, because the thinnest steel tubulars of mast size are on the order of 18 - 16 GA (standard chain link fence posts are usually 17 GA) and these thicknesses are on the lower edge of weldability and very vulnerable to corrosion and local buckling induced by impacts. This corresponds to 0.150 or thicker aluminum, which is usually associated with a pretty big mast section. Thus a steel mast may be appropriate only for some large craft. It is a simple analysis to make though, and it is worth checking. From: cdbarry@h... Date: Mon Jun 11, 2001 2:43 am Subject: Line heating Just a comment, somewhat off subject, though perhaps not. Most large commercial shipyards use line heating to form double curved plates. This method uses a cutting torch with the cutting oxygen turned off and a water hose to intentionally distort the steel into various curves, including compound shapes. It is used instad of heavy machines because it is much faster and more accurate. Getting back to the subject, what about subbing in a plate with double backset along the chine of an origami boat? From: "John Callahan" Date: Mon Jun 11, 2001 2:02 pm Subject: Re: Line heating > Getting back to the subject, what about subbing in a plate with > double backset along the chine of an origami boat? With appoligies. I don't understand your question. Are you talking about a doubler plate for strength or inserting a curved plate to eliminate the hard chine? John From: "Gary H. Lucas" Date: Mon Jun 11, 2001 11:43 pm Subject: Re: [origamiboats] Line heating CD, The problem I see is that there is quite a bit of residual stress at the chine because the plates are only bent to shape without overbending to take a permanent set. I think making a cut would cause the hull to spring out of shape unless really well restrained somehow. Gary H. Lucas From: "Phillip Allen" Date: Tue Jun 12, 2001 12:08 am Subject: Fwd: Masts & (spars in general) This is my first post here and is a question/questions. In reading the posts concerning masts I have wondered if we're talking about a sailing boat or a space shuttle. Considering that it would be easy to taper a steel mast by telescoping and then welding smaller sections to the larger base, weight aloft (how much weight are we talking about, anyway?) might be minimized. As a (hopefully) future along distance cruiser, maintenance skills within my own grasp are attractive. Yes, aluminum may be welded...but, maybe not by just anyone. The other thing I must consider is that, likely, I won't be able to "choose" the material used. It will take all my resources to purchase the boat and will cause me to look for "bargains"...what about wood spars? How does wood compare with steel and aluminum for weight and strength? How much additional hardware would be required for wood? From: "Alex & Kim Christie" Date: Tue Jun 12, 2001 5:06 am Subject: Re: [origamiboats] rounded chine > The problem I see is that there is quite a bit of residual stress at the > chine because the plates are only bent to shape without overbending to take > a permanent set. Just a thought, but I am thinking here that the residual stresses might also be inherently good for creating a stress-skin which adds to overall stiffness of the hull. Another question to ponder: would there be much of a hydrodynamic difference between a hull such as this with its very short hard chine, vs a hull like this with a rounded corner in the same area? It may be that the work involved to create a rounded chine (which is underwater, mostly), might not be worth the effort if it doesn't yield a big difference in performance. Alex Christie From: pvanderw@o... Date: Tue Jun 12, 2001 1:40 pm Subject: Re: rounded chine Does anyone know what Ted Brewer does for his 'radius bilge' designs. I was under the impression that he used a section of pipe, but I don't actually know. At any rate, I think that worrying about the chine radius is not 'origamiboat' type thinking, i.e. if you are going to insist on a fancier boat, why start with origami construction. IMHO, without anything to support it, I doubt that replacing the chine angle with a radius will matter unless the radius is quite large, say 6" or more. Peter From: willyacht@y... Date: Tue Jun 12, 2001 2:15 pm Subject: Re: Fwd: Masts & (spars in general) You have some valid points. If you really wanted to get advanced, you could select a spring steel or any steel with a high carbon content about .5% or greater, taper the mast then get the whole thing heat treated. This would give you enormous strength probably with same ability to bend and recover as aluminium. Because you using high strength carbon steel you could also use a thinner gauge. Minor weakning from welding could be planned carefully and it would not be hard to retemper with a oxy torch after working or joining the sections together. There are companies now who can heat treat extreme lengths. Not worrying about loosing your mast and shelving out 10 grand brings piece of mind! Will From: cdbarry@h... Date: Wed Jun 13, 2001 3:27 am Subject: Re: rounded chine I understand most radius chine hulls are rolled plates. A typical line heated plate would have 6-12" of transverse backset in thirty inches of span, which, if it was a radius, would be fairly large - a couple of feet or more. Line heating a single plate is about a shift or so, including the sight templates, so we are only talking about 16 manhours or so of extra labor to eliminate the chine altogether. From: cdbarry@h... Date: Wed Jun 13, 2001 3:28 am Subject: Re: Line heating > With appoligies. I don't understand your question. Are you talking > about a doubler plate for strength or inserting a curved plate to > eliminate the hard chine? John An insert. From: cdbarry@h... Date: Wed Jun 13, 2001 3:31 am Subject: Re: Fwd: Masts & (spars in general) If you need higher yields, there are plenty of readily weldable HSLA steels. However, these steels (and QT steels) only have higher yields and yield doesn't effect stayed mast strength. From: "Gary H. Lucas" Date: Wed Jun 13, 2001 1:56 pm Subject: Update on devolpable surfaces I've been playing with creating 3D models of an Origami hull in Rhino. I have made a little progress. I can create a hull of sorts and it unfolds to a flat pattern with little problem. The command that creates a conical section which can be unrolled in Rhino is call RAIL REVOLVE with ScaleHeight Option on. You need to supply an arbitrary axis ( I used a vertical axis ) in order for the command to work. It appears there are some fairly large limitations on the hull shapes that can be generated. The bow must have a fairly long overhang, otherwise you get a crease line running from the end of the chine to the bow. I am not a boat designer and I have little idea of real boat shapes. What I have done so far is draw a top view of the sheerline that kind of looks good, picked a chine location in a similar fashion and then an arbitrary location for the end of the chine where the bow conic section would start. Unlike working with a flat pattern that you must fold up to see what it will look like I can go through quite a few variations to what changes in a fairly quick way. I will post some images once I get a better handle on this. Gary H. Lucas From: pvanderw@o... Date: Wed Jun 13, 2001 4:03 pm Subject: Re: Update on devolpable surfaces If I correctly interpret what you want, then a typical axis would be strongly raked aft (more than 45 degrees). It would originate at a point just about under the bowsprit, and a foot or so on the 'other' side of the boats centerline. From: kupris1948@a... Date: Thu Jun 14, 2001 1:25 pm Subject: deck prisms Is there any way to make these? The commercial ones are expensive, and I need 2 to 4 of them. John From: brentswain38@h... Date: Sat Jun 16, 2001 3:50 am Subject: Re: Line heating When Gunter Richtler cut the chine out to radius it on the first one of my boats he did, he did the cut with no support, and the hull sagged considerably. Good support is neccesary. Brent Swain From: "Alex & Kim Christie" Date: Sat Jun 16, 2001 4:00 am Subject: Re: [origamiboats] deck prisms Could they perhaps be made of solid block of Acrylic? What is it that makes a prism do its thing? If we can crack the code on it, we should be able to replicate it. From: cdbarry@h... Date: Sun Jun 17, 2001 2:04 am Subject: Re: Update on devolpable surfaces If you can find a copy of Ullman Kilgore's article on developable surfaces from the FAO fishing vessels series this will help find the true rulings you need. You can also download a series of points on both chines and search for zero warp using the definition of co- planarity. This would not be too hard with a spreadsheet. I promised to upload a copy of an article on developables on the SBYD site, (www.sbyd.com) but haven't got around to it yet. It was an article in Boatbuilder magazine a while back. If you are interested, a professional level suite for doing this type of thing (and much more) is Ship Constructor from www.albacoreresearch.com. I think you can download a demo. From: cdbarry@h... Date: Sun Jun 17, 2001 2:06 am Subject: Re: deck prisms It's just a matter of simple optics. Any optical physics book will have the needful information. The angles have to be corrected for the different material index of refraction. From: "Gary H. Lucas" Date: Mon Jun 18, 2001 1:51 am Subject: Got It! part 2 It's been raining like mad so I took some time to play. The attached JPGs show two renderings of an attempt at producing a 3D origami hull. The third JPG shows the unrolled pattern. I cut it out and taped it together, it looks like a boat. Lots of playing here. This is supposed to be a 30' long by 9' wide hull. Notice the reverse transom, and the little extra piece at the chine. I tried to see if you could make it multi-chine, to soften the sharp edge. On the paper model this is quite effective at making the hull look rounder. The stern is kind of excessively V shaped to my eye. I haven't yet figured out the defining curves to make it rounder, without a reverse kink in the transom. Gary H. Lucas Attachment Hull Unrolled.JPG Type: image/jpeg Size: 96k Download Attachment Hull 2.jpg Type: image/jpeg Size: 58k Download Attachment Hull 1.jpg Type: image/jpeg Size: 45k Download From: "Alex & Kim Christie" Date: Mon Jun 18, 2001 5:53 am Subject: Re: [origamiboats] Got It! part 2 Keep up the good work, Gary! Definitely reveals the inner workings of the geometry at work with this system. I'll put your hull models into the group files for future members to see. Alex Christie From: brentswain38@h... Date: Mon Jun 18, 2001 10:21 pm Subject: Re: deck prisms There is only so much light which can get through a deck prism, the amount of light striking the surface. All the prism does is spread the light around a lot . Any piece of acrylic or other transparent material ground to the same shape will do the same thing.The shinnyness of the inside surface shouldn't make much difference. Deck prisms are a notorious source of deck leaks. If you make your own with a stainless base welded in ,it shouldn't be hard to do a better job of engineering it to be easier to work on and get a good seal than the commercially made ones . Personally, I'd be more inclined to put plexiglass panels in the cabintop where they would take less water over them than on the deck.It's easier to learn to live with less light than to learn to live with deck leaks. Brent Swain From: "Alex & Kim Christie" Date: Mon Jun 18, 2001 10:35 pm Subject: Re: [origamiboats] Re: deck prisms Would a panel of plexi in the cabin top, combined with a triangular (in section) piece glued to the under side do the job of spreading the light? Or would a piece of plexi alone do the trick, then paint the inside of the cabin a light colour to diffuse the light? Or maybe a nice little disco ball from Radio Shack hung just below the plexiglass? ;) Alex Christie From: "Gary H. Lucas" Date: Mon Jun 18, 2001 11:49 pm Subject: Thoughts on painting I am currently working on repainting a 1979 Catalina 22 that needed a lot of glass work. As I wet sanded the hull between coats of paint for the umpteenth time my thoughts were on what it would be like to have a metal boat. Specifically the difference between a steel boat and an aluminum one. I hear everyone say what a wonderful easy material steel is for building a boat, especially with today's modern paints, then I think about how much I hate painting! It's been said that steel boats rust out from the inside, so that means you also need to do as good a job painting inside as you do outside. The finish isn't important but thorough coverage is, and there are LOTS of nooks and crannies to deal with, as well as painting in dark corners and over your head. Then there is the prep work, grinding and sandblasting both inside and out. In a few years the outside needs to be painted again, and I would guess after 10 to 20 years the inside will need work too, only now it is covered up by everything you put inside the boat. Finally while a steel boat is cheaper to build, older steel boats seem to sell for very little money. A boat can be built from aluminum that is equally as strong as a steel boat, by making every thing thicker, yet it will still be 50% or more lighter. When you are building it all the pieces are much easier to handle because they are so much lighter. Welding aluminum out of position ( vertical or overhead ) is easier than welding steel. When you are done welding and grinding, you are done with the finish, inside and out, except for bottom paint. Electrolysis can be a problem but there appear to be lots of ways to deal with that problem. It appears that when you finally decide to sell the boat aluminum boats bring a premium price, even more than an equivalent fiberglass boat, so building the boat may have been quite a good investment if done well. Okay so aluminum DOES cost considerably more than steel for the raw materials but with all the above in mind why would you want to spend lots of hours and have a reduced return on your investment to own a steel boat, rather than an aluminum one? I work with aluminum every day, it is easily my favorite material to work with. So what am I missing here? Gary H. Lucas From: winslow59@y... Date: Tue Jun 19, 2001 2:49 am Subject: Gary, a link to a couple articles... Michael Kasten wrote some articles about aluminum, steel, and boat building -- they're worth reading. Look for them on his website. http://www.kastenmarine.com http://www.kastenmarine.com/articles.htm -Markus From: "Doug Barnard" Date: Tue Jun 19, 2001 10:57 pm Subject: New to List- what about trawlers? I've been reading the discussions on this List, and find it fascinating. My wife and I are planning on building a 48' steel trawler that was designed by Charles Wittholz. The framing is the traditional method, with longitudinal stringers on 5" X 1/4" transverse frames about every 2'. Can these methods be adapted for a full-displacement boat of this size? The 300 hour time period to assemble a boat that Brent Swain mentioned really blew my mind! I'm mailing off a check today for $23 US for Brent's book. Even if origami techniques can't be used on the hull, I'm very interested in finding ways to fabricate whatever I can. Brent mentioned in one of his posts, "I usually buy the plate wheelabraded and pre primed with a cold galvanizing primer ( 80 % pus zinc ) Straight from the steel supliers." I've called at least 15 steel yards in the Los Angeles area, and *all* of them have never heard of blasted and pre-primed steel, and haven't a clue as to where I could find it. Any suggestions? From: "burr.halpern" Date: Wed Jun 20, 2001 2:08 am Subject: Wittholz designs I used to work for the late Charlie Wittholz. Charlie was very careful in engineering his designs. I would be very hesitant to delete any structure from his designs without having a marine engineer check what you are proposing first. Charlie was neat guy and a very good yacht designer. Good luck, Jeff From: cdbarry@h... Date: Wed Jun 20, 2001 3:06 am Subject: Re: New to List- what about trawlers? Farwest Steel, Eugene OR - They have an 800 number. You will also have to talk to them about your welding techniques to choose an appropriate primer. They will also CNC off of DXF burnsheets. This is another technique for quick construction. Note though the wisdom of many small shipyards "we always make money on steel, but outfit eats our lunch". Find out about modern outfit techniques for shipbuilding as well so you don't have to spend four years fitting out a hull you built in two months. From: cdbarry@h... Date: Wed Jun 20, 2001 3:22 am Subject: Re: Thoughts on painting I've designed dozens of aluminum boats both as a consultant and in shipyards. Aluminum is a good material, though the actual weight savings is closer to 20-30% not 50%. Note that the Kasten articles use an incorrect value for aluminum yield. If you need to develop scantlings for an aluminum boat, and do not wish to hire a naval architect or a yacht designer, take a look at NVIC 11-80 at www.uscg.mil under marine safety and environmental protection. This is a widely used scantling rule that can be downloaded free, though it is for crewboats. The ABS "Rules ... Offshore Racing Yachts" cover sailing yachts, but you will have to buy it at www.eagle.org. (ISO is developing rules for aluminum recreational boats, but they are not yet available to the general public.) The drawback to aluminum are that it has lower strain energy to rupture (less tough), that you have problems with piping and fittings, that you have to be careful of electrical systems, that anti-fouling paint is a problem, that it has to be GMAW welded, that it can't be line heated and that it is more expensive than steel (though this may not be true overall for any given project - run the numbers). SOme of it's other advantages over steel are somewhat overstated as well, such as the ease of welding - GMAW on aluminum is faster than SMAW on steel, but GMAW on steel is as fast, except as you note, overhead. (And push only rigs are cheaper than push-pull or spool on gun rigs that are advised for aluminum.) All that said though, aluminum is a very good material for boats. You have to look at the overall costs of the project and you situation and run the numbers. From: "Doug Barnard" Date: Wed Jun 20, 2001 4:41 pm Subject: RE: [origamiboats] Re: New to List- what about trawlers? Thanks for the reply! > Farwest Steel, Eugene OR - They have an 800 number. You will also > have to talk to them about your welding techniques to choose an > appropriate primer. That sounds great! I hope that shipping doesn't kill me on this... > They will also CNC off of DXF burnsheets. This is another technique > for quick construction. I've found that to be extremely expensive, and shipping on that could also be problematic. I plan on building everything that I can, so I find it hard to justify paying through the nose to save some plasma cutting. I'm a man of limited means and I guess that I'm not that much in a hurry! > Note though the wisdom of many small shipyards "we always make money > on steel, but outfit eats our lunch". > > Find out about modern outfit techniques for shipbuilding as well so > you don't have to spend four years fitting out a hull you built in > two months. Any sources of info? It seems like in Roberts' "Steel Boats" and Smith/Moir's "Steel Away", the concentration is mainly on hull and deck structure. There doesn't seem to be much on putting the rest together. I'm looking forward to Brent Swain's book to fill in the gaps. This sounds like a interesting area that could use some real discussion, I'm all ears! From: "Doug Barnard" Date: Wed Jun 20, 2001 4:41 pm Subject: RE: [origamiboats] Wittholz designs > I used to work for the late Charlie Wittholz. Wow, that must've been great working for Charlie! I've spoken with his widow, and she's supposed to be sending me out a catalog of his motor designs. You bring up an excellent point, and echo my deepest fear about the folded steel method. How do we validate designs? Most good traditional steel yachts are probably very similar below decks, and have similar specs. I'm not in the position to pay a folded steel designer to design me up a 48' trawler from scratch. So where do we go? Does anyone know of a good marine engineer that is hip to the folded steel thing that could help me out? I've asked Brent Swain if he could be hired to adapt me plans, but haven't received a reply. From: cdbarry@h... Date: Wed Jun 20, 2001 10:15 pm Subject: Re: New to List- what about trawlers? > I find it hard > to justify paying through the nose to save some plasma cutting. ? Last time I asked, most places included plasma cutting in the metal price or real near. What high cost are you talking about? > Any sources of info? You will have to look at some professional level shipbuilding stuff - try to get "Ship Production" via interlibrary loan, or go to the UCLA engineering library (you can get a UC library card with your CA driver's license) and look up "Journal of Ship Production". It's heavy going, but scanning through back issues will give you an idea. Calkins did a good paper on small ship advanced outfit a few years back. From: "Doug Barnard" Date: Wed Jun 20, 2001 10:51 pm Subject: Plasma cutting !!!! I've been quoted thousands of $$$. Like 30 cents an inch. These are third party guys, with a small shop. Designers like Buehler and Roberts charge thousands of $$$ just for the cutting files. If "most places" that you know of will do this, that's great! "Most places" that I call just want to sell me a sheet of plate and get the hell out. They are uniformly ignorant of anything else that I might want done with it. Guess that I've been looking for love in all the wrong places! You mentioned Far West in Eugene, OR. Got any others? So the way to go is to develop the hull, loft all the parts in the computer, arrange them on the equivalent sheet size, write a dxf, and email to one these "most places"? Wow! Wouldn't life be grand then! From: "Gary H. Lucas" Date: Wed Jun 20, 2001 10:46 pm Subject: Re: [origamiboats] Re: Thoughts on painting Thanks CD, I am quite familiar with aluminum welding, and so much of what I see is BAD! The problem is that a lot of people try to use short arc welding on aluminum, and if you want any strength you have to use spray arc. Spray arc is much faster, cleaner and nicer looking than short arc anyway. I have a Miller spool gun running off a gas powered CC welder at work. When I went to buy it none of the dealers even wanted to quote on it for use with a CC machine. Changed one jumper and works just fine, a little different but we still get good welds. Push welding aluminum is a joke, nothing but trouble. If you are going to weld aluminum get a spool gun and be done with it. Gary H. Lucas From: brentswain38@h... Date: Thu Jun 21, 2001 1:37 am Subject: Re: Thoughts on painting The steel laying on the ground for my 36 footer costs roughly $6,000 . The aluminium costs $20,000 . A friend with a lot of cruising experience (circumnavigation, etc.) and a master scrounger , doing his own work , had one of my 36 footers sailing for $14,000 and was on his way to Hawaii for $17,000, still less than the cost of the aluminium alone for the same boat . The boat was extremely well built.This is before you include welding equipment , gas , wire, etc. You can build a trawler, or any other hard chine boat using the origami method, then put in afterwards , any additional structural you feel comfortable with, saving a tremendous amount of time and money over the traditional "imitation wooden boatbuilding"methods . The worst you could do is end up with a little extra weight and work. I design only sailing vessels, and don't have any experience or interest in powerboats, altho I'd be happy to do whatever I can to help make the job easier . Brent Swain From: brentswain38@h... Date: Thu Jun 21, 2001 1:57 am Subject: Re: Thoughts on painting If the inside of a steel boat is properly painted with at least 3 coats or more of epoxy tar it should never need painting. My last boat was built in 1976 and is still going strong . The original inside paint is still there. One of my 36 footers , built in 1984 was recently surveyed with ultrasound and the hull was very close to it's original thickness despite a 7 year circumnavigation. Several of my boats were sold more than ten years after they were built for several times what their owners had in them ,some sold several times for the same price. From what I've seen ,steel boats hold their value as well as any other boatbuilding material if they are properly built, maintained and painted in the first place. Only those which have been unpainted inside, or badly neglected , lose a great deal of value.This is true , of course ,only in places where people understand the value of a steel boat. It may not be true in places of extreme consumer programming where people have been brainwashed by the peddlars of trendy plastic , to the point where the glossy ads do their thinking for them. From: cdbarry@h... Date: Thu Jun 21, 2001 3:01 am Subject: Re: Plasma cutting Plasma Northwest in Seattle, (Don Regan, as I recall), and Everett Steel, Everett WA are two more. I like working with FarWest though, and they cut for half the boat builders who don't cut their own all the way from Bellingham to Crescent City. Ask for Elaine Brotherton. Shipping really isn't that big a deal anyway. However, you can probably find plenty of others closer in TomCat. From: cdbarry@h... Date: Thu Jun 21, 2001 3:06 am Subject: Re: Thoughts on painting --- In origamiboats@y..., "Gary H. Lucas" wrote: That's my point, you can't use low end steel rigs for aluminum (though I've been told that a push rig with an oversized Teflon liner works sort of). I prefer a push-pull like a Cobramatic. From: cdbarry@h... Date: Thu Jun 21, 2001 3:21 am Subject: Re: Plasma cutting We would log into their computer over the phone and upload our files at the end of the day. The next afternoon (or maybe the day after) we would get a truckload of plate. A lot of yacht designers doing CNC don't have the best (most productive) software, etc. or aren't even doing their own work, so it's very expensive. In the latter case, the whole boat has to be redrawn from scratch, so it's really costly. The trick is to find someone who: 1) Really knows metal boatbuilding. 2) Does both the design and the CNC in house in one continuous process. 3) Uses one of the major shipyard software packages like ShipConstructor, AutoShip Builder, FORAN, TRIBON, etc. not just a hull fairing package and bare bones CAD. (If you go to www.albacoreresearch.com you will see what I mean by productive packages.) From: "Alex & Kim Christie" Date: Thu Jun 21, 2001 6:19 am Subject: Re: Thoughts on painting Thanks, Gary, for your thoughts on painting steel: > > there are LOTS of nooks and crannies to deal with, I think the main thing with Brent's frameless boats is that there are vastly less nooks and crannies to deal with when compared to framed boats with their myriad transverse frames. The inside photos shown in the "Austin Hull" photo file show a very clean and bare interior, with the green primer already in place, needing no expensive and messy sandblasting - just clean up and prime the few welds (remember, there are less welds in an origami boat). Framed boats would offer a very different picture. I admit it is very attractive to not have to do any painting inside an aluminum boat. But I too have seen the insides of some very mature steel boats (again, properly built, properly maintained), and have been very impressed by their condition. With wheel-abraded pre-primed plate, there is no need to do expensive sandblasting inside and out. That primer is stuck some good! The issue of sandblasting is often cited when comparing cost-wise to aluminum. With pre-primed plate, however, that cost can now be factored "out' of the equation, likely bringing steel out ahead in cost. It is commonly available in Canada, but I don't know about elsewhere. (Americans, just come up to Canada to build your boats, I'll lend you my back yard!) Aluminum, however, is a really neat material, and I am going to be using it for my outboard skiff without hesitation. For bigger boats, it can be wonderful too, though the welding needs good quality control for proper strength. Vulnerable stress points have to be religiously avoided to prevent fatigue damage (not that you can ignore this with steel, but to a lesser degree). This is critical for the high-speed aluminum powerboats built out here on the coast. Done right, aluminum is perfect for such craft, which get the tar pounded out of them on a daily basis. Certainly if the powerboats can be properly designed/engineered/constructed for severe service, then the same can be done for sailboats. But initial and over all cost outlay is a big factor in many people's minds, so steel often comes into play once again. The aluminum vs steel question is going to be ongoing, because both materials have aspects worth considering, and both have drawbacks, all moderated by each given situation. I'd say the best thing to do is draw up a list showing the pros and cons of each material as they apply to your resources, abilities and available work space, then see which wins out. Each person's list will be slightly different, depending on what tools and space they have access to, and how big their initial budget is. The ability to build steel Swain boats in the open is a big plus for a lot of people on this coast, who are building right in their side or back yards in the middle of cities, and would never be allowed by city authorities to build a large shop first, even a temporary one. Alex Christie From: "Alex & Kim Christie" Date: Thu Jun 21, 2001 6:36 am Subject: push-pull? Sorry, need some education for me and the group on what Push and Pull mean here! Alex Christie From: Richard Payne Date: Tue Jun 19, 2001 6:22 am Subject: Re: [origamiboats] Thoughts on painting Gary, go with the material you feel most comfortable with. My steel yacht has been in the water 14 yrs and is still on the original paint. Once each year I go aboard with a 12cfm compressor, a needle gun and a handheld grit blaster and touch up any rust spots. In between times I just cover new chips with 5 minute Araldite, or rusty bits with lanocote grease. Inside, any rust gets the grease treatment. Eventually I needle gun it, wire brush it ( the brush on a small angle grinder) , rinse it liberally with fresh water (most important) and then when dry coat it with fishoil, or sometimes with half fishoil and half silver paint. When thoroughly dry, it gets coated with one of the rubberized tars that they use to waterproof shower enclosures with. This lasts for years. I guess if anything rusts through you can weld in a new piece easily and retain original strength. Rust usually looks worse than it is, and if you design your interior so that you can see most of the inside of the hull through lockers, slatted linings etc. you can keep on top of it. I would be much more scared of electrolysis in an alloy hull, which can be rapid and deadly! Regards, Richard. From: cdbarry@h... Date: Thu Jun 21, 2001 12:59 pm Subject: Re: push-pull? GMAW (MIG) guns feed wire into the weld instead of using stick electrodes. The wire can be mounted on a spool on the gun or in a separate box connected to the gun by a hose which also carries shielding gas and current (and maybe cooling water). If its separate, the spool can be larger, the gun lighter and smaller. To feed the wire down the hose, you have motorized drive wheels that pinch the wire. You can have the wheels at the box end (push) or the gun end (pull - though this is rare) or both ends. Rigs intended for steel are often push - it's cheaper and results in the lightest possible gun. Aluminum is softer than steel and push rigs tend to jam, or even if they don't they feed at an iregular speed which changes the arc length and hence its characteristics, especially the type of metal transfer through the arc which is very important. There is a lot of other stuff related to selecting GMAW equipment as well, especially the characterististics of the power supply (CC, CV, Pulse, etc.) that can be researched on the web. A very good source for all things welding is www.lincolnelectric.com. The education section has numerous books, training materials, videos, etc. at ridiculously low prices. From: cdbarry@h... Date: Thu Jun 21, 2001 1:05 pm Subject: Re: push-pull? Push rig http://www.lincolnelectric.com/products/wprod/powermig255.asp Push-pull rig http://www.lincolnelectric.com/products/wprod/recpk98/300cobr.asp From: pvanderw@o... Date: Thu Jun 21, 2001 2:09 pm Subject: For purposes of comparison... For those of you doing comparison of origami vs. standard construction, and of steel vs. aluminium, there is some interesting info about an aluminium Van de Stat 34 here: http://www.green-witch.50megs.com/ This boat has been under construction for about 2 years and is still mostly an empty hull. There are a lot of the builder's opinions, to which you may feel free to disagree. Mr. Swain's friend could have built his boat and sailed to Australia and back in the same time. There is a 1986 steel version of the boat for sale in Florida for about $30,000. Peter From: "Doug Barnard" Date: Thu Jun 21, 2001 4:54 pm Subject: RE: [origamiboats] Thoughts on painting > Rust usually looks worse than it is, and if you design your interior so > that you can see most of the inside of the hull through lockers, slatted > linings etc. you can keep on top of it. So your boat has an un-insulated hull? You don't get major condensation that wrecks the insides of those lockers? From: brentswain38@h... Date: Thu Jun 21, 2001 8:50 pm Subject: Re: Thoughts on painting An uninsulated hull is only an option in warm climates. People who tried that here in BC found that it often rained hard with condensation inside when it was clear and sunny outside.They produced many gallons of water per day while living aboard in the winter. During cold spells the entire inside of the hull ,with the exception of a three foot circle over the stove , was coated with a half inch layer of ice for weeks on end.Everything which came in contact with the hull became saturated in an hour or two , then froze solid when it got cold. Sheet foam insulation kept the boat warm, but condensation behind the foam was runing like a river despite any attempts to build a vapor barrier. Fibreglass insulation became a soggy mass in a day or two despite any attempts at a vapour barrier. With sprayfoam , the inside of the boat was as warm and dry as any appartment building. The salt from the salt shaker poured easily and stuff in lockers stayed dry.There was only one exception. If there was a piece of steel the size of your fingernail poking through the foam , it wiould drip like a leaky faucet ,with condensation. For this reason, when you have your boat foamed , it's best not to let the foamer leave until you've checked the boat several times for missed spots. It's also not a good idea to trim the foam flush with the beams and stringers. If the hull has been given at least three or more coats of epoxy tar before foaming, it's good for life.If it' hasn't been properly painted, it may last a vey long time, or it may rust out fairly quickly regardless of conditions during the foaming.There seems to be no logic as to which it will do. Brent Swain From: Richard Payne Date: Thu Jun 21, 2001 9:54 am Subject: Re: [origamiboats] Re: Boat building texts. I found Boatbuilding With Steel by the late Gilbert Klingel extremely good. It was my "bible" when I built Nekeyah. Published by International Marine Publishing Company, Camden, Maine. 1973 Hopefully it is still in print in a later edition. Don't get too excited about cheap hulls - it is the fitting out that costs the big dollars. Regards, Richard. From: brentswain38@h... Date: Sat Jun 23, 2001 1:26 am Subject: Re: Boat building texts. What percentage of the total the hull represents depends on how good a scrounger you are . The advantage of steel is that stainless cleats and many other fittings can be built from scrap for a tiny fraction of what they cost new. When the metal work is done, you have your hatches , cleats . chainplates, anchors, bowroller, self steering, etc, etc, all stuff you have to buy for other kinds of boats. My 31 footer cost $4,000 to launch and $6,000 to get sailing and living aboard.I did my scrounging well in advance. Brent Swain From: Richard Payne Date: Fri Jun 22, 2001 10:03 am Subject: Re: [origamiboats] Thoughts on painting When I built Nekeyah I glued that white koolite stuff about 25 mm thick onto the hull and deck inside except around the stove, here I used a more fire retardant version. We are near Sydney Australia so our climate is not that cold (no frosts where I live!! ). I have no transverse frames except for the floors, and have used tubular longitudinals. The only places I have had corrosion inside has been the water traps at the lowest parts of my longitudinals. I now have bits of cloth glued into the low spots and hanging down into the bilge to act as wicks to draw any moisture from these low spots. My advice is to get rid of any water traps and your internal corrosion problems will be minimized, no matter how much condensation you experience. Regards, Richard. From: "John Callahan" Date: Mon Jun 25, 2001 9:15 pm Subject: Hull material ?'s Boat's I've built in the past were of either carbon steel, ASTM A36, or Corten construction and a skiff or two of Aliminum, 5052, I've been wondering about building using 304 ASTM A240 stainless steel. I think the ideal stainless would be 316L for salt water aplication but the cost would be prohibitive. I think the chloride stress corrosion problem associated w/ 304 can be circumvented with the proper application of paint. My question would then be.. What thickness of 304 stainless steel would equal, say, 3/16" ASTM A36 carbon steel, What physical properties do you look at to make the comparison, Hardness, Tensile strength's, Elasticity, all of the above?. For example, Ultimate tensile strength of 304 is about 1/3 greater than that of A36, Does this mean I could use 1/3 less material thickness? The weight savings, 5.04 lbs/sq ft vice 7.66 lbs/sq ft using the a 3/16" vs 11 GA. as an example. Does this come close to the lbs/sq ft of a fiberglass hull? John From: brentswain38@h... Date: Mon Jun 25, 2001 10:38 pm Subject: Re: Hull material ?'s I remember reading a story about a frenchman who has done a lot of cruising ,who built a boat out of stainless and said it was a big mistake. He had lots of electrolysis and welds cracking everywhere. If you have to protect it with paint, then what's the point. Any 304 I've used below the waterline has had major corrosion problems. I've had no problems with 316. As long as you use stainless trim on all the corners where paint can be chipped off , above the waterline ,don't over detail , and paint the boat properly in the first place, a steel boat can be extremely low mainteanance . I average an hour or two out of every year and less than $50 on maintenance, and my boat is 17 years old. Except for a few chips here and there, the original paint is as good as the day I put it on. Brent Swain From: "Norm Facey" Date: Tue Jun 26, 2001 7:55 pm Subject: spray foaming inside a steel hull I agree totally on spray foaming inside a steel hull - makes an incredible difference - and hangs on very tightly too - BUT - if it gets thin (less than 1/4 ") in an area that is routinely wet (in my case, the hull bilge where it attached to the keel), water will penetrate, and now you have a mess on your hands. Paint the interior first, then spray foam. Areas I'm still pondering are: - the bilge between the bow (read anchor locker) and keel - last boat was foamed in this area, so condensation was not an issue - but it was most definitely not smooth, so water would puddle without draining. Do I leave an unfoamed water way to provide drainage through to the keel sump, or not? How do I get a clear flowing drainage path if I do foam? - the anchor chain locker - here the foam was crushed to a significant degree by the anchor chain, primarily in areas where it was thin (over top of a stringer or frame). I like the idea of foaming all over - but how do you protect the foam, maintain drainage, and support the heavy, mobile weight of the chain clear of the hull? - beneath the motor - paint, foam & paint again? (to seal foam from diesel fuel/motor oil). Norm From: "Gary H. Lucas" Date: Tue Jun 26, 2001 10:49 pm Subject: Re: [origamiboats] For purposes of comparison... This boat was discussed quite a bit on the Metal Boats Forum. I took a look at the construction pictures, there sure are LOTS of little pieces! One of the possible reasons it is taking so long is that Tony insisted on Tig welding the hull. He also didn't believe some of us that suggested that his 250 amp machine was way to small for something of this size. I wouldn't be surprised if he had lots of trouble with warping because of the small welding machine. If the machine is too small you will not be able to travel very fast and most of your heat will be absorbed by the surrounding metal, which will expand and cause warping. Like steel you always want to weld with the least amount of heat input, which means traveling fast. I also found the pictures of his efforts to insulate the hull with rigid foam interesting. It appears he is only insulating between the frames, not over them. If you think a steel boat sweats where there is any exposed metal, imagine what aluminum with its MUCH higher thermal conductivity will do! Gary H. Lucas From: "Gary H. Lucas" Date: Tue Jun 26, 2001 10:55 pm Subject: Re: [origamiboats] Re: Boat building texts. Brent, I believe you mentioned here somewhere about installing a floor in your boat to increase the stiffness of the hull in the area where the keels are attached. I looked at all the construction pictures in the archives and when I looked at the pictures of keel installations I was a little surprise at how little reinforcing there was in the area of the keels. Have there been problems with flexing in the keel area? I am very sensitive to this issue, because I once owned a 1976 Hunter 27 which nearly had the keel fall off. Hunter 27s from 75 to about 78 had a basic engineering design flaw that weakened the hull in the keel area by a huge amount. I repaired it properly but it was a huge job. Gary H. Lucas From: "Norm Facey" Date: Tue Jun 26, 2001 11:22 pm Subject: S.Stl as a hull material Seems to me sub waterline corrosion due to differential oxygen concentration is the reason you do not use S.Stl as pilings, or to build boat hulls. Per my wife (who's the metalurgical specialist), it's all sensitivity to chloride corrosion. Either way, the conclusion is the same - stainless steel is a bad material choice for building a hull - even a reasonably prepped mild steel hull will out last it. From: "John Callahan" Date: Wed Jun 27, 2001 3:51 pm Subject: Re: S.Stl as a hull material Don't ask me how many years ago it was but I seem to remember an article in one of the Sailing rag's about a Stainless steel sailboat. I think it was called the "British Steel". I've searched for current information on this boat but can't come up with anything. Maby it was my imagination. Stainless steel is used in ship construction. 316L (L for low carbon) is the choice material for this purpose but is twice the price of regular 304. 304L is also a good choice for salt water use but its close to the price of 316L. I arn't an engineer, but i'm thinking, perhaps since ss is less ductile than mild steel it's more apt to crack at stress points. Maby a mild steel hull w/ a 304 ss deck? Less weight topside, better corrosion resistance, It would still have to be painted and maintained but you wouldn't get a rust streak every time you scratched or chipped the deck. John From: "John Olson" Date: Wed Jun 27, 2001 8:55 pm Subject: Re: spray foaming inside a steel hull I originally sprayfoamed right down to the centreline on my twin-keeler. It was suggested to me by the foaming company that I glass over the foam in the bilge to stop water penetration. I did this, and then painted over with a urethane-based intumenscent paint. After about 10 years, I found that the foam was saturated with water, but only about 4-5" up the side from the bottom of the bilge. It appeared to be starting where things like anchors, etc, had punctured the glass and the foam. I scraped out the foam to about 12" up from the centreline. The 3 coats of high-build epoxy under the foam were in perfect condition. I added 3 more coats of coal tar epoxy on the bilge area and up over the exposed edge of the foam and there's been no problem since. Cheers John From: "John Callahan" Date: Thu Jun 28, 2001 1:39 pm Subject: Re: spray foaming inside a steel hull In chain lockers, under the auxiliary and Lazerette's I've covered lagging and insulation with stainless steel sheet. Make cardboard template's, carefully marking where bends are required, transfer template to sheet metal, cut bend, fit, etc. They can be secured with cres banding, sheetmetal screws, pop-rivets, or adhesive. Also makes for a sharp locking locker. John From: "Doug Barnard" Date: Thu Jun 28, 2001 6:20 pm Subject: Your book Got my check yet? My wife and I are just dying to read your book! From: "Doug Barnard" Date: Thu Jun 28, 2001 8:50 pm Subject: RE: [origamiboats] Your book Whoops! Sorry about the wrong address... Please ignore! From: brentswain38@h... Date: Thu Jun 28, 2001 9:36 pm Subject: Re: spray foaming inside a steel hull Chain lockers tend to be high enough in the hull to allow any water to drain out of, or away from the foam. This is not the case in the bilge area or under the engine. In such places , it's only a matter of time beforwe water and ,or oil inevitably finds it's way into the foam regardless of what you cover it with. Given that it's such a small area compared with the rest of the boat , it's best to avoid foam there altogether as the problems with foaming these areas far outweigh the advantages of doing so. Once foamed, you have no way of knowing what's happening behind everything until major dammage has resulted. Insulating the floor above the bilges can drastically reduce the amount of condensation in the bilge, as can throwing down a piece of carpet for the cold seasons. Brent Swain From: yah02840@y... Date: Fri Jun 29, 2001 2:30 am Subject: Re: S.Stl as a hull material It is common practice in France to use Stainless Steel for decks and to use a liberal amount of it for detailing. Bow chocks, cleats, tracks. etc..An approach as far the hull is concerned is to use 304 or 316 SS extrusions or flat bars for longitudinals and framing. From: Richard Payne Date: Fri Jun 29, 2001 6:10 am Subject: Re: [origamiboats] Re: S.Stl as a hull material Have you thought of metal spraying? i.e. grit blast and then use a gun to plaster the whole lot with coats of melted aluminum and zinc. I made all of my rails and stanchions from mild steel and had them treated this way and it has been 100% successful. This is a pretty established and time tested process. I wish I had had the money to do the entire hull, inside and out! Having said the above, I still think that corrosion on a properly protected steel boat is a very minor concern, much much less than the problems you would have with crevice corrosion, weld decay and heat distortion with a stainless one. The thing would be an absolute nightmare! It would also be an "orphan" and difficult to sell when the time came. Remember, amateur boat builders tend to be individualists, a very special breed of people, but most of the rest of the population flock toward the sheep end of the spectrum and shy away from anything too different. Regardless of how you feel now, you will one day want to sell your creation and this becomes an important factor. Regards, Richard. From: brentswain38@h... Date: Wed Jul 4, 2001 8:49 pm Subject: Re: Your book Doug Your book is in the mail. Canada post aint too swift, like the political hacks who run it. Brent Swain From: brentswain38@h... Date: Wed Jul 4, 2001 9:08 pm Subject: Re: S.Stl as a hull material A friend bought a metal spraying gun at a garage sale for $60. The owner thought it was a paint sprayer. He then bought the whole outfit , flow meters, guages , hoses etc for $300 used, The aluminum wire he bought was quite cheap, but the oxy acetylene wasn't . He was still able to do the job, tools , materials and all included ,for a fraction of the price of hiring someone to do it , and he still had the equipment to sell at the end of it .He was told the US military was dumping all their equipment and going for the electric guns. That equipment probably ended up in a scrapyard for a dollar a pound . A group of boatbuilders in Victoria once chipped in and bought the equipment ,and did their own boats for a fraction of the cost of having it done, then sold the equipment. The resulting job worked extremely well. I once flame sprayed a boat. I found it very important to keep the gun clean. The spray started out very fine and the steel was barely warmed. As the tiny holes in the gun alongside the wire gradually filled up, the spray began to splatter, and the steel got hotter.It also didn't stick as well. It was time to take the gun apart and clean out the tiny holes. When that was done, the spray was again as fine as fine sandpaper, and the steel stoppped warming up. For a first class job, the gun should be cleaned frequently. I've seen the results of military tests on flame spraying ,and the aluminium spray was far superior to zinc. Aluminium costs more per pound, but at a fraction the weight of zinc, covers a lot more surface per pound at a given thickness. Aluminium woud probably take more oxy acetylene . Brent Swain From: "Gary H. Lucas" Date: Wed Jul 4, 2001 9:45 pm Subject: Re: [origamiboats] Re: Your book Brent, I also ordered your book about three weeks ago. Is mine in the mail as well? Gary H. Lucas From: brentswain38@h... Date: Sat Jul 7, 2001 3:43 am Subject: Re: Your book Yes. It's in the mail. From: "Gary H. Lucas" Date: Sat Jul 14, 2001 3:48 pm Subject: Brents Book I got Brent's book in the mail on Thursday afternoon, finished reading it by 11:30 pm. It's an easy read, and I read pretty fast so, don't take that as comment on the content. It has lots of good ideas on how to build your own boat inexpensively. I was little disappointed though in how little information there was on the actual design of an origami hull. I suppose this is what you would call proprietary information, but it would have been very interesting to me. I may never actually build my own boat, but I'm very interested in the process of how the design comes about. I note that in the back there are drawings and specs for three boats. I am assuming that Brent sells plans for these boats, and isn't living off the proceeds from a $20 book! If that's the case then Brent needs to sharpen his sales skills a little. It would have been real nice to have plans prices, a list of what is included with the plans, and an address and ordering information for getting the plans. Gary H. Lucas From: "Doug Barnard" Date: Sun Jul 15, 2001 6:38 pm Subject: spray foam fires? > National Fisherman did an article about a year ago relating to the fire > dangers of spray- in foam. Most of this is polyurethane and once > it catches > on fire it is nearly impossible to put out. It is still being > used but the > Coast Guard is looking seriously at not allowing it on inspected vessels. > It may be worth looking at more fire resistant alternatives. Fire is still > one of the leading causes of death among the Alaskan fishing fleet. Thanks for the tip! An excellent cite- do you happen to know the issue date? I'd like to pick up a back copy and spread the word around. In a brief search, I found that the Flexible Products Co. (makers of "Great Stuff" canned spray foam, available in hardware stores) makes a product called "Froth-Pak" that is fire retardant. A quote from the web page: "Question: Is the Froth-Pak fire-retardant? Answer: The 25FS version of the Froth-Pak (available in the 180 and larger kits) is considered to be fire retardant. It will burn if exposed to open flame, but it is self-extinguishing when the source is removed." I guess that wood or fabric could fall into that category, as well. I can see that loose wiring could rub and short itself, and when in direct contact with the foam, start a fire that way. I was planning on running standard plastic conduit, and foaming that into place. From: Richard Payne Date: Mon Jul 16, 2001 11:24 am Subject: Re: [origamiboats] spray foam fires? Check out the products of combustion of foams. I know that some generate highly toxic gases, and that even a small fire can therefore be extremely dangerous. Regards, Richard Payne. From: cdbarry@h... Date: Mon Jul 16, 2001 12:57 pm Subject: Re: spray foam fires? There is an extensive Coast Guard report on the subject that can be found by searching the Coast Guard site, www.uscg.mil, probably under marine safety and environmental protection. Also look at the NVICs, especially "Voluntary safety standards for fishing vessels" (probably 5-86). From: brentswain38@h... Date: Tue Jul 17, 2001 2:26 am Subject: Re: Brents Book -Plans for the 26 are $200, for the 31 $300, for the 36 $350 and for the 40 $500.They can be ordered the same way as the book. Designing an origami boat is done the same way as designing any hard chine boat, then the plate shapes are taken from the drawing, or off a model and an origami model is made. It can then be lofted full size into the plate and construction begins. I'm not much of a salesman or hustler, as long as my income matches my outgo, I don't worry too much about the numbers in some banker's computer.As I live aboard and keep cruising full time, I've never had to pay moorage on my current boat, and my cost of living is tiny .I support neither vehicle, nor ex's, nor booze nor nicotine, nor offspring (don't have any that I'm aware of.) Cruising can be cheap as long as you do it at sea rather than in the bars. Brent Swain From: brentswain38@h... Date: Tue Jul 17, 2001 2:39 am Subject: Re: spray foam fires? A friend was doing a bit of welding on his 36 footer in Frisco Bay, when the foam caught fire. The entire aft end of the boat was gutted and the loran was melted into plastic stalagmites and stalactites. Despite the extreme heat , any place where the foam was painted with cheap latex paint, it wouldn't burn. This wasn't the intumescent , fire retardant paint, just cheap hardware store latex paint.The fire couldn't get enough oxygen through the paint to support combustion. Even the fire resistant intumescent paint sold by pitsburg and other manufacturers doesn't add up to a great expense in the greater scheme of things.It's well worth while painting the entire inside of the boat after foaming and triming the foam, before puting the interior in. Intumescent paint foams up when heated to form a protective insulating ,non combustible , carbon like foam which insulates the foam from the flame . This material can be scraped off and re heated several times before there isn't enough left to protect the foam from an open flame. Brent Swain From: "Sigge Johansson" Date: Tue Jul 17, 2001 11:24 am Subject: Origamo 45? Hello Brent Are 40 the upper limit for the Origami method? Or is it possible to build a 45-footer? With a rudder under the hull -- skeg supported? (so far I've only seen pics on Origami boats with aft hung rudders) If Yes: What would the price tag on that plan package be? Regards, sigge From: "Shelley & Foster Price" Date: Fri Jul 20, 2001 12:03 pm Subject: Irony rope to chain splice Hello Guys I'm looking for the instuctions for the "Irony" rope to chain splice for three strand - this is the one where the rope goes down the chains links instead of round and being backspliced. I know its in Brion Toss's book but there isn't a copy round here, it was also written up in "Practical Boat Owner" mag recently. I know the basics of the splice but I need to know more about its properties and how to size the rope to chain. Regards - Foster From: "Doug Barnard" Date: Mon Jul 23, 2001 6:13 pm Subject: RE: Re: Waste Heat Recovery > From: owner-trawler-world-list@s... > [mailto:owner-trawler-world-list@s...]On Behalf Of Alex Hirsekorn > Waste heat is also routinely used for watermaking on large ships > (often with an assist from excess vacuum). This link shows some systems > built by Alfa Laval that are too large for our purposes. Again, systems > such as these should be scaleable. The above post, combined with a "what if" from Brent Swain's "How to Build a Better Steel Boat", gave me a bit of inspiration for a watermaker that uses waste heat. It requires a dry stack installation. I've uploaded a schematic to the TWL Attachment Archives (thanks Paul!): http://www.whooppee.com/TWL/distiller.jpg A float valve in the cool tank turns on a raw water pump when the level falls too low. The cool tank in connected to the hot tank by an open pipe, thus maintaining a constant water level between the two. As water is evaporated, it goes into the 1/2" copper line which is coiled in the cool tank, condensing it. The water jacket would also provide insulation from the heat of the exhaust stack as it passed through living spaces. Tank construction would be of scrap stainless steel. Any commentary? Hey, maybe this could be turned into a moonshine still! :) From: "Doug Barnard" Date: Tue Jul 24, 2001 5:05 pm Subject: Re: Waste Heat Recovery > From: Michael Schooley [mailto:schooley@k...] > Looks like a nice simple design. I think you might be onto something really > good. However no engineer can resist suggesting a few changes; Lord save us from the engineers! :) > 1 Add a brine bleed to the bottom of the hot tank, otherwise the salinity > will increase until it reaches 100% and the still stops working. Gotcha on that one. > 2 To recover some of the heat from the brine before you dump it overboard, > you could put the line from the cold tank to the hot tank inside the brine > bleed line. This makes it a reverse flow heat exchanger. I was thinking that the pipe would be short, about an 1 1/2" in diameter. This would make the unit fairly compact. As the brine dump wouldn't happen continuously, would this really be worthwhile? > 3 Make the hot tank and the exhaust pipe concentric pipes. The drawing was purposely exaggerated to show the concept, but I was thinking of maybe an inch or so of clearance all 'round the exhaust pipe. > 4 Use a platelet heat exchanger for the cold chamber and condensation line > and reverse the flows. > even though they cost more than scrap stainless, I think the compact size > and efficiency be worth the cost. Yikes! That little jewel looks expensive. I was thinking of a coil of 1/4" or 1/2" copper line inside the cool tank. You work for NASA? :) Also, I'm not following this "reverse the flows" thing. That chart is nice, but how does the water flow? How would you get it to go backwards? > 5 Since you are using the hot chamber to shield the living spaces from the > exhaust heat (I think this is a really good idea by the way!) you don't want > to ever let the hot chamber run dry. However when the fresh water tanks get > full, the water/steam has to have somewhere to go. Therefore, I suggest a > pressure relief valve at the top of the exhaust stack. The other alternative > would be a pressure relief valve on the fresh water line, just prior to the > storage tank, vented overboard, but that means another through hull. That sounds good. Though I think that thing isn't going to work quite that well that I have to worry about all of the spare fresh water that I would have to get rid of! > 6 Once you add a pressure relief valve to the hot chamber, you might as well > match it to the operating pressure of the water system and eliminate the > fresh water pump. All you need is a check valve and a pressure accumulator. I don't think that there will be that much pressure! If so, I would want to relieve it immediately. > 7 Since you will have hot water half-way through the condenser, add a tap in > the middle to feed the hot water tank. This would mean a custom plate heat > exchanger, unless you use two in series and take the hat water before the > second heat exchanger. Uh oh, too complex! Too many parts! :) > 8 Since you will have pressurized steam on board, feed it to one of those > cool sounding steam whistles like the old tug boats used to have and > activate it with a pull chain in the pilothouse. I think that you're seeing "boiler" and I'm seeing "evaporator" in this design. As fine as it would be to come motoring into port, toot-tooting on my steam whistle, jaw thrust forward and chest swelling with manly pride, with this system, all I would get is a flaccid sigh. Trying to build pressure vessels is way beyond my level of expertise! Thanks for the commentary! From: winslow59@y... Date: Tue Jul 24, 2001 11:56 pm Subject: MBS Festival Are any of the OrigamiBoats members planning to attend the Metal Boat Society Festival? Are any Swain/origami boats likely to be there and available for viewing/inspection? http://www.metalboatsociety.com/festival.htm From: brentswain38@h... Date: Fri Jul 27, 2001 1:22 am Subject: Re: MBS Festival There are none of my boats going to the Metal Boat Festival that I'm aware of . There possibly would be if it were in Oak Harbour as usual, but they decided to have it near Portland, Oregon, a long way from most of my boats, and many other boats from BC and Washington. Brent Swain From: brentswain38@h... Date: Fri Jul 27, 2001 1:31 am Subject: Re: Waste Heat Recovery A friend tried this without much success. I believe his tank was too big.There is a limit to how much water you can boil with a limited amount of heat source.A vacuum pump would drastically lower the boiling point. You would have to flush the salt out frequently. Brent Swain From: brentswain38@h... Date: Fri Jul 27, 2001 1:41 am Subject: Re: Origamo 45? The biggest boat I've designed(or have any interest in designing ) is the 40 footer. You can biuld any hard chine hull using the origami techniques . You can take the plate shapes off the lines drawing by computer, or make a model and take the plate shapes off the model.The rest of the building proccess is the same. The stringers can't be much heavier, or they'll have trouble bending, but you can put in more of them, or stack them after the hull is together, for added stiffness. In aluminium they can be bigger. An inboard rudder makes the self steering and inside steering options fragile, expensive , and extremely complex. There is no way the rudder can be made as strong and reliable as it is with a transom hung rudder. Brent Swain From: stephenw@t... Date: Sun Jul 29, 2001 10:57 pm Subject: Non-origami boats allowed? Greetings, I have just purchased a Roberts 35 sailboat hull, deck and cabin. Right now it's just a big empty tin can, still in red primer. It will be an engineless boat with a schooner junk rig. I am dealing with junk rig issues on the junkrig list. I have lots questions relating to finishing this boat. Also questions related to sourcing new or used things like galvanized portholes and an anchor winch, and design for building a self steering for spade rudder/tiller. I am also interested in information on strengthening the boat to accept unstayed cedar masts. Any advice will be greatly appreciated. Stephen Wandling Vancouver, BC From: neilhuget@c... Date: Mon Jul 30, 2001 1:06 am Subject: Re: [origamiboats] Non-origami boats allowed? Hi, www.boatbuilding.com is all you need to know also, www.sailnet.com...read all the articles by "sue and larry", they home built a 34 junk rigged boat, sister ship to annie hill's Badger From: "Gary H. Lucas" Date: Tue Jul 31, 2001 12:04 am Subject: Re: [origamiboats] Re: MBS Festival I would have liked to attend this affair, I didn't hear about it until too late to change my travel plans. I flew from NJ into Seattle on Thursday, then to Yakima and back home again on Saturday. It would have been nice stay for a few more days and get something more out of the $1674 the customer spent on my airfare! Gary H. Lucas From: "Gary H. Lucas" Date: Tue Jul 31, 2001 12:09 am Subject: Re: [origamiboats] Re: Brents Book Brent, A little self promotion would never be considered to be hustling. The world DOESN'T beat a path to your door even you have the greatest thing the world has ever seen. You still have to put up signs to guide people, and that is all I was suggesting. So what is included in your plans set? I am considering buying a set to further my education, as it seems unlikely I'll ever get around to actually building my own boat. I do however go sailing frequently so all is not lost. Gary H. Lucas From: brentswain38@h... Date: Wed Aug 1, 2001 12:10 am Subject: Re: Brents Book Plans include the basic shell(hull,deck, rudder, skeg , keel ), mast,rigging, sails, tankage, hatches,hatch hinges , deck layout ,interior layouts, detail drawings (hatches, self steering, bow roller, rudder fittings , chainplates , mooring bitts , cleats , handrails,ballast,exhaust, keelcooler,mast support, tabernacle etc. The book has drawings for the roller furling, anchor winch , self steering, engine mounts running pole fittings ,jibsheet leads,dinghy,chine doubler plates, sheerlegs,mast support,tabernacle, bow roller, head, etc. Brent Swain From: "Patrick" Date: Thu Aug 2, 2001 4:12 pm Subject: Free Steel Hi all, I have a bunch of steel for anyone that might want it for free. It was formed for some kind of shoring for some really big ditches, thats all I can find out about it. A few of the pieces are 35 feet long but most are in the 10 foot range. It is all 3/8ths inch thick. Jut as a wild guess I would say there is 50,000 pounds plus of this stuff. If anyone wants it, it's free for the taking but you will need a crane or very large forklift and a flatbed semi with a 40 foot trailer. Just let me know. The price is right anyway. From: "Patrick" Date: Thu Aug 2, 2001 5:26 pm Subject: Brents book I know its probably here somewhere but I need the url to order the book. TIA From: "Doug Barnard" Date: Sun Sep 2, 2001 7:02 pm Subject: RE: [origamiboats] Free Steel Where you located? From: "Pat Folk" Date: Thu Aug 2, 2001 7:14 pm Subject: Re: [origamiboats] Free Steel I am in Stockton CA...the central valley and not far from Sacramento From: "Gary H. Lucas" Date: Thu Aug 2, 2001 9:52 pm Subject: Re: [origamiboats] Brents book Patrick No internet ordering or credit card orders as far as I know. Brent's book is available by mail from him directly: To order a copy of Brent's book "How to Build a Better Steel Boat a Heretic's Guide" (illus.,100 pages paperback) send $20 plus $3 for postage to: Suite #427 1434 Island Highway Campbell River BC Canada V9W8C9 From: "Alex & Kim Christie" Date: Sat Aug 4, 2001 6:13 am Subject: 36 foot bare Swain hull for sale in Nanaimo For anyone looking for a bare hull to get a head start on their project, I just spotted this ad in the Vancouver Island "Buy, Sell and Trade" publication: -------------------------------------------------------- 36' Brent Swain designed hull and deck - steel. All metal work can be finished onsite. She lays in Nanaimo and is available to view. Steel was mill-abraded/primed. $13,000 (CDN) (250) 714-2422 (Nanaimo, BC) --------------------------------------------------------- I called the number and enquired further about it, reaching the father of the owner. This single-keel bare hull has cockpit, pilothouse, decks and coachroof on, but is not yet ballasted. Rudder has been built and is ready to hang. Stringers to be installed still. Evan Shaler has performed the work on it to date, and estimated another 200 hours welding work left to go. The people are selling it for $1000 less than what it cost to build to present stage. I think it is a pretty good deal for anyone who wants to bypass the time and labour aspect on such a project. The fellow who commisioned it has been laid up with an injury in Portland Oregon, and cannot complete the vessel. The above number will get you his father, Franz, who lives aboard in Nanaimo, and appears to be handling the sale of the hull for his son. Just a phone number for contact at present, until Franz contacts his son for e-mail address. I may go buy and take some digital snaps when I can, and will post to files. International enquiries can e-mail me if they like, and I can pass on messages to Franz's cellphone, as I am in the same province, just one hour north. Alex Christie From: Stephen Wandling Date: Sat Aug 11, 2001 8:39 pm Subject: Coatings in Vancouver I have heard some horror stories, here in Vancouver, BC, about overly thinned epoxy that has to be redone in a couple of years, and I hope to avoid practitioners that do less than satisfactory work. If you have any sandblasting/epoxy companies that you can recommend, or recommend against, please let me know. I am also interested in getting the same type of info on urethane foaming companies. Stephen From: brentswain38@h... Date: Mon Aug 13, 2001 7:01 pm Subject: Re: Coatings in Vancouver Dave Johnston of Tasman Industries does excellent sprayfoaming. Brent Swain From: brentswain38@h... Date: Mon Aug 13, 2001 7:06 pm Subject: Book postage Rates I've found that air mail of my books to Europe , New Zealand and Australia is around $10. Surface mail is around $5 . When ordering it could you please specify if you want it sent air or surface and include adequate postage. Brent Swain From: Stephen Wandling Date: Tue Aug 14, 2001 5:56 pm Subject: Shrinking plating Brent, Thanks for the sprayfoaming reference below. What is your opinion on fairing the plating on a non origami boat that is bulging (in usually) because of the welding to frames and longitudinals surrounding it, by heating the plate at the bulge red hot with a tiger torch and quenching it with a mat of towels soaked in cold water? I recall you had suggested jacking out a bar placed at the bulge and tacking it to the frames when it's in position. Do you have an opinion on the pros and cons of these methods? Some info I have received re the heat/quench method is that you have to get the steel temperature right. In other words, does it need to be 'almost' red hot, or cherry red, etc. I am also told that you only get one chance with this method and attempting to do it again can leave the steel in an annealed state? Cheers, Stephen From: brentswain38@h... Date: Thu Aug 16, 2001 9:06 pm Subject: Re: Shrinking plating You're right , you only get one shot at it. If it doesn't move enough, you can always try the flat bar method.The flat bar method is probably a lot easier. I wouldn't worry about anealing, as heating and quenching does the same thing each time, so the steel remains the same.The point is you aren't going to accomplish anything by doing it more than once. When you heat the metal it wants to expand, but being surrounded by metal, it can't , so the molecules are squashed closer together. When you quench it, they contract further than they would have otherwise. Brent Swain From: brentswain38@h... Date: Thu Aug 16, 2001 9:07 pm Subject: Re: Shrinking plating Hotter the better, short of meltdown. Brent Swain From: Stephen Wandling Date: Fri Aug 17, 2001 1:10 am Subject: Re: [origamiboats] Re: Shrinking plating I was doing fine until we got to the "short of meltdown" part! And how does one know when one is approaching this critical point? Are there colour stages you go through, for example? Stephen From: "Gary H. Lucas" Date: Fri Aug 17, 2001 2:13 am Subject: Re: [origamiboats] Re: Shrinking plating Stephen, Unlike aluminum which goes from shiny to GONE! almost in the blink of an eye, steel is very forgiving in this respect. You heat it and it gets redder and redder until it starts getting white hot before it finally starts to slump. I wouldn't worry too much about overheating. If you decide to use an oxyacetylene torch get yourself a rosebud tip and a LARGE bottle of acetylene. You don't need the large bottle because of the amount of gas required, you need it because acetylene is dissolved in acetone in the bottle and the rate you can draw off is limited by the surface are of the liquid in the bottle. An indication that your bottle is too small is when the torch starts popping like fire crackers. What is happening is you are drawing off acetone vapors that explode when they reach the flame. This can be very dangerous because you often get a blowback into the torch where the flame is burning down inside the torch. If you don't turn off the torch immediately it will melt down in your hands! The amount of heat an oxyacetylene torch with a large rosebud tip can put out is absolutely amazing to see, something around 500,000 BTUs in a flame about 1" in diameter! This is important because this bending method works best when you can heat a very small area to a high temperature very quickly. The slower you heat the bigger the area that gets hot and the less bending you get. Hope this helps. Gary H. Lucas From: Stephen Wandling Date: Fri Aug 17, 2001 5:01 am Subject: Re: [origamiboats] Re: Shrinking plating Gary, Phew! I'm pleased to learn of steel's forgiving nature. I gather both from Brent and yourself that a lot of heat is needed. I had initially been told that a 'tiger torch' burning straight propane would suffice. The sections I will be heating will be about 20" x 20" and the plate is 1/8". Right now, I don't own an oxyacetylene torch set, but could easily arrange for one. There are only about a half a dozen 'dents' that need to be dealt with. Thanks for the advice. Stephen Wandling From: Richard Payne Date: Fri Aug 17, 2001 8:41 am Subject: Re: [origamiboats] Re: Shrinking plating I don't like welding shell plating to transverse framing, especially above the waterline where distortion shows. Have you tried removing the problem weld with an angle grinder before heat shrinking? Regards, Richard Payne. From: cdbarry@h... Date: Fri Aug 17, 2001 2:12 pm Subject: Re: Shrinking plating This general technique is called "line heating" and is well established in shipbuilding, not only for removing distortion, but for producing curvature in the first place. Four passes on one line is the limit for producing continued movement unless you induce prestress in the plate, but that is only because it becomes less effective, not because it's damaging. Line heating is approved by ABS, etc. for most shipbuilding steels any home builder would encounter. A concentrated heat is used and water quench is generally applied in the immediate area. A cutting tip with the cutting oxygen turned off is the approved tool. From: Stephen Wandling Date: Fri Aug 17, 2001 4:37 pm Subject: Re: [origamiboats] Re: Shrinking plating You bring up an interesting point. This is a Roberts designed hull and therefore it has transverse framing and longitudinal bars. I did not build this hull and didn't receive any 'manual' regarding how the construction details were to proceed. It would appear, since the longitudinals are 'floating' in slots in the transverse frames, that the longitudinals were intended to be pushed out and tacked to the plate. I am unclear whether the longitudinal is then supposed to be welded to the transverse framing after being fastened to the plate. It does appear that the longitudinals are only meant to be tacked to the plate and not continuos welded (or maybe the welding hasn't been completed). As I am only just starting this work, I will have to take a careful look at the boat later today, but I believe that the plate isn't welded to the transverse frames in the area adjacent to the bulges, but only tacked to the longitudinals, with the longitudinals 'floating' in the slotted transverse frames slots. Almost all of these 'bulge' areas are forward and generally seem to be 'created' by the close proximity of the adjacent chine welds, which incorporate a chine bar which may add to the problem as it has significant welding. Would your recommendation be for me to cut all welds from the transverse frames to the plating, with the exception of at the chines? I recall that Brent Swain's experience is that more damage occurs at the transverse frame and chine bar areas when a steel boat experiences a grounding. I will contact Bruce Roberts and get confirmation on the intended welding pattern for the transverse and longitudinal framing. Thank you for your comments. Stephen Wandling From: Stephen Wandling Date: Fri Aug 17, 2001 4:45 pm Subject: Re: [origamiboats] Re: Shrinking plating Am I correct in assuming that 'induced prestress' might be achieved by jacking out the longitudinal and the plate in the area of the bulge? Would it then be appropriate to use line heating while the stress is in place? In lieu of a cutting torch, in your opinion would a 'tiger torch' fired by propane be an adequate tool for heating areas up to 20" x 20"? Thanks for the info. Stephen Wandling From: "Gary H. Lucas" Date: Fri Aug 17, 2001 7:09 pm Subject: Re: [origamiboats] Re: Shrinking plating Stephen, CDBarry's recommendation of a cutting torch with the oxygen off makes much sense that what I suggested. I was thinking your hull plating was much thicker. But the reason a cutting torch is used is because the preheat flames, which are all you have without the oxygen jet, are VERY concentrated on a small area and very hot. This is ideal because the less metal you actually heat to bright red, and the more the area around it stays cool the better the metal bends. Any torch which does not use pure oxygen for combustion will produce lots of BTUs but in a much larger area. Think Sledge hammer versus ball peen hammer. Experiments are being done using lasers to bend complex shapes by rapidly heating very small areas and some of the results I have seen pictures of are really amazing. Gary H. Lucas From: brentswain38@h... Date: Sat Aug 18, 2001 1:32 am Subject: Re: Shrinking plating Longitudinals are normally welded for about 2 inches every 6 inches. Fully welding them would create an enormous amount of distortion. Not tacking transverse frames to shell plating and leaving the longitudinals to float off the transverse frames when the longitudinal chine welds shrink, greatly reduces distortion.Welding heavy metal, like chine bars ,to light plate always causes distortion. Designing chine bars into a steel boat doubles the amount of welding and is a bad idea. Doubler plates inside the chine are a far better way to make the chine reefproof, without the distortion ,and such doubler plates are only needed amidships on single keel boats. Forceing the longitudinals out of the transverse frames with wedges may cure a lot of distortion. Brent Swain From: Stephen Wandling Date: Sat Aug 18, 2001 8:05 pm Subject: Transverse & Longitudinal framing What are the prime purposes served by transverse (TF) and longitudinal framing (LF) in a hard chine boat? The Roberts I am working on has 2" x 3/16" bar for transverse frames and 1" x 3/16" bar for longitudinals, with 1/8" plating. I am trying to get my head around how this is all supposed to work together. It is my understanding that in Brent's boats you only have longitudinal framing and only in the middle 2/3 or 3/4 of the boat? I gather that is to support and/or strengthen the curved sections? But, don't you have transverse framing in the cambered cabin top? The TF in my boat is not welded to the plating at all. It is welded to the chine bars and is tacked to the LF that sets in slots. The LF is tacked to the plating, while the chine bars are welded continuously. I should say that the LF is 'supposed' to be tacked to the plating. In fact it isn't in many areas, such as around bulges in the plating. After removing the bulges, should I bring the LF into contact with the plate and tack it? Also, at the first frame aft of the bow, the LF are well out of their slots in the TF. Should I weld in tabs to make this connection? Another concern is that the LF bars are not all straight, and in fact many 'snake' their way through the boat in many areas. My limited engineering understanding tells me that they don't have any of the required strength if they aren't straight. It would be a messy job to cut all of the welds to the plating and shorten these LF members, but if it's absolutely necessary then I will have to do this. Some time you have to wonder at the 'bargain' one buys. Stephen Wandling From: Richard Payne Date: Sat Aug 18, 2001 12:37 pm Subject: Re: [origamiboats] Re: Shrinking plating I agree with Brent that you should space out your longitudinals with wedges and then let them pull in with the welding. Chines do not necessarily mean distortion though. Nekeyah is triple chined with chine tubes. To fit the chines to the frames, offsets were plotted on the ground and marked by pegs. The tubes were then run through a rolling machine which I made and which cold rolled the necessary bend into them. Each panel was plated in two lengths of plate. Once they were accurately fitted to the chines, some scraps of flat bar were lightly tacked on edge to the chines outside the plates. The butt welding was then done and the plates were allowed the necessarily shrinkage movement. Only after this were the plates tacked onto the chines. All outside welding was completed first to pull a bit of an outward bow into the plates. Welding was staggered , max. 3 inches at a time. This worked well and our hull is pretty fair with no filler needed at all. When the hull was complete, I removed all of the transverse frames ( keeping the floors and bulkheads ) as the designer confirmed that they are more for ease of construction than structural strength, and provide places where you can't paint properly and thus rust traps. It was all a lot easier than it sounds, just time consuming. Regards, Richard. From: WIJNANDA69@H... Date: Mon Aug 20, 2001 2:50 am Subject: scrap/salvage/usefull boat stuffs I will be driving from the Juneau, AK. area to Sacremento Ca.area and was wondering if I could get some leads on places to scrounge for suitable parts for a 36' steel sailboat. The names/locations of places where I can get anything from steel tubing for trim to used sails and stoves for cheap. (i.e. Pac Marine Exchange, Popeye's, Boeing surplus) as we all know every little bit helps. Thanks From: "Doug Barnard" Date: Mon Aug 20, 2001 4:12 pm Subject: RE: [origamiboats] scrap/salvage/usefull boat stuffs Well, this isn't near Sacto, but in So. Cal, a great place to check out is Walt's RV in Fontana (out near San Bernardino). They're a surplus/used parts dealer for RV parts. They have good deals on stoves, and thousands of used windows. I got my surplus windows for my current boat, dual pane sliders about 30" X 20", for $35 each. From: "Doug Barnard" Date: Mon Aug 20, 2001 4:12 pm Subject: finding building locations Any tips as to how to scrounge up a suitable location for a bit of shipbuilding? I'd like rent to be as cheap as possible (free?), so going with realtors or agents would preclude that. Weather isn't all that much of a factor, so an open stretch of field would be just fine. Obviously you can't ring the doorbell of a house that isn't there- how do you locate the owners? I'm also thinking about attaching wheels to the hull (temporarily, of course!) so that if I have to beat a hasty retreat, it won't be that much of a problem. Sometimes a "handshake" deal can suddenly go sour. There must be some sort of farm equipment thing that would do; any idea as to what a set of four wheels, with two steerable is called? Skeletal trailer? Hay hauler? From: "Pat Folk" Date: Mon Aug 20, 2001 7:22 pm Subject: Re: [origamiboats] scrap/salvage/usefull boat stuffs I posted earlier that I have a bunch of free steel if you want that. email me privately if your interested in it. But it will take a flatbed to haul it and a crane or large forklift to load it. From: Stephen Wandling Date: Wed Aug 22, 2001 6:54 am Subject: Sequencing I am trying to work out some sequencing issues that appear to be important to me. Several involve dealing with spaces that will be enclosed when the sandblasting/coating is done. The first involves the integral water tanks. These are intended to be built of mild steel and be cement wash coated on the inside. The tank bottom areas of the hull are presently covered with a mild rust. Can I just build the tanks on the rusty hull, cement coat them and consider that there will be no further corrosion because the surface will not be in contact with air? The other area is the fin keel. Can I assume the same thing here: That placing the ballast (lead), either in a melted form or set in pitch or resin, will seal out the air? Also there will be plates welded on top of the ballast area and I could add the oil as suggested by Brent Swain I believe. There is already surface rust inside the fin keel. There's lots of info out there, but some of these types of issues aren't dealt with. Maybe I should just go on common sense, but it can't hurt to ask. Cheers, Stephen Wandling From: cdbarry@h... Date: Thu Aug 23, 2001 12:37 pm Subject: Re: finding building locations This is not quite to the subject,but you may want to look at modular construction and block outfitting. The idea (aside from the fact that modularization saves labor both in construction and outfit) is that you could build each module in a smaller space, then just get the big space to join up. From: brentswain38@h... Date: Thu Aug 23, 2001 8:56 pm Subject: Re: finding building locations Modular construction doesn't work with origami construction as the plates used are 8ft by 36 ft or larger. One can do 1/3rd of the steel work in advance by building everything which can be built before doing the hull ( cleats, habdrails , hatches, rudder, stanchions mast and fittings,bow roller,bilge pumps, heater, thru hulls, valves, anchor winch, mast tabernacle, anchors , etc, scrounge ballast,wood, paint,sails, rigging ,engine, etc. That way once you get the shell together, it takes a fraction of the time to finish the boat.It also reduces the burnout rate. Brent Swain From: "Ronald" Date: Tue Aug 28, 2001 10:44 am Subject: Hallo all out there help needed found this in the photo section... Bella Via of Comox 44' double-ended steel Swain junk double ended I'm looking for why, well living in France but all my friend in Norway and 44' should be as me 45 and my wife 44 exact the lenght we are looking for a oceangoing sailing home.......44 lod could be a nice low and fat and deep, means to me liveabord and sail so where to go...to get a plan as stell for me is the way to go building intelligent and not old fashioned whu not and junk sail....easy and singlehanded i like that please help Ronald From: Stephen Wandling Date: Tue Aug 28, 2001 4:43 pm Subject: Re: [origamiboats] Hallo all out there help needed Ronald, You can contact Brent Swain at brentswain38@hotmail.com and I am sure he will be able to give you all of the information you need about building one of his designs. Cheers, Stephen Wandling From: brentswain38@h... Date: Wed Aug 29, 2001 1:32 am Subject: Re: Hallo all out there help needed Try jackaranda@h... The boat belongs to Jack Carson. He bought a bare hull 36 footer and did some severe modifications. She is long and low, but narrow and not particularly deep. Brent Swain From: brib@a... Date: Sun Sep 9, 2001 3:09 am Subject: interesting day it's been a very interesting day reading the last 324 messages. I have been attracted to the idea of searching out the apparent freedom suggested by the single-handed sailing experiences of Joshua Slocum. I saw Brent Swain's boat construction on the website of the interior builder whose ethics were earlier (albeit falsely) in question, while fascinated by the metal boat building and Spray copies of Bruce Roberts. It wasn't until I found the magic look-up word, origami, that I came upon this group. The rough and ready product shown in the photos of Brent's 31 footer, and the wilderness setting of the construction of one of the boats, have me convinced that a budget conscious builder has no real alternative to turn out a solid and safe boat. The spirit of Slocum is alive and well in the no nonsense, solidly sensible approach to boats and sailing evinced by Brent Swain's techniques and execution. This is the closest thing I've seen to the situation offered to Slocum when he was kicking about before rebuilding the Spray. I want to know if an apartment dweller such as myself can put together a plan to build one of these boats. It looks like a game plan detailing materials and tools, labour requirements, a determination of cost to produce an enclosed hull with a three coat tar epoxied, foam insulated, and latex painted interior within the shortest period of time, is the first major hurdle. I'll be sending a check shortly for Brent's book. I'm curious to know why Brent has settled on the 31 footer when so many seem to think bigger is better. Congratulations on a great discussion group. Brian From: "Alex & Kim Christie" Date: Sun Sep 9, 2001 5:46 pm Subject: Re: [origamiboats] interesting day Hello Brian, Welcome to the discussion and thanks for starting a new thread in the currently quiet halls of origamiboats group! Well, your last question about size was an excellent one, and I'll respond with my reflections, gathered from conversations with Brent in the past since I have had very similar thoughts. The going theme these days seems to be, "bigger is better", but in my view the closer your boat is to being a "ship", the more energy and money it will take to build and maintain, and the less independent the sailor is, thus negating the real reason for undertaking the project in the first place. Slocum avoided the complication trap with Spray, which was considered at that time a "micro-ship" compared to the usual world-sailing boats of the time. Whereas painting the hull of a 31 or 36 foot hull in an afternoon can be a relatively simple and sane (maybe even pleasurable?) process, the painting of a 50 foot hull is a real "job" and much less of a casual affair. Relating things to "human scale" helps keep things in perspective for me: According to Brent's and others' experiences, the 36 foot half-shell hull plates appear to be the upper limit that two people working together can rock back and forth and manouver into place by themselves. Beyond this size, one is going to need specialized equipment suited to the task. Some people may have suitable equipment, but most don't. I know that pulling the hull together is only a one-time thing, but one can use this as a frame of reference for future activities with the boat too, such as haul-outs, maintenance and handling the boat at dock or at sea. I liked your comparison of what this boatbuilding process offers with Slocum's spirit. I think that puts it all into a nutshell: build it, and go! Alex From: "Doug Barnard" Date: Sun Sep 9, 2001 6:18 pm Subject: RE: [origamiboats] interesting day Currently, the primary problem that I'm finding is the ability to locate a building site. The local homeowner's assn. is starting to give me grief over re-building a 20-footer, they'd for sure flip over a start-from-scratch project! The idea of getting halfway through and getting evicted has me scared, but I don't want to rent some huge, high-dollar commercial space to get this done. Being in the L.A. area doesn't help matters much, either. Wheel-abraded pre-primed steel in So. Cal. is also a problem. You boys up in the Northwest have all the good suppliers! > I'm curious to know why Brent has settled on the 31 footer when so > many seem to think bigger is better. Congratulations on a great > discussion group. Brian I'm looking to modify a traditional 48' full-displacement trawler design to origami methods. I've just finished a major design rev, and have made the otherwise all-business design into something more sexy and streamlined. I'm working the boat up in a 3D package- if anyone wants to comment, I have an .avi of a complete flyaround. Or I can send stills... Be careful about being too time-conscious, as if you aren't totally into the process, you can make dreadful mistakes or burn out. Maybe start with the ship's dingy, to get your chops down? Brent talks about building sub-systems first, so that they can be attached to the hull when it's done. Fortune favors the brave! DB From: brib@a... Date: Sun Sep 9, 2001 8:10 pm Subject: picking up the thread I may be a few years from making a run at this, but I would like to clarify some of the logistics involved in carrying out a building program As I understand it, 31 feet is sufficient to cruise the world, even though I recall that Slocum with his slightly larger craft had mused that if he were allowed the opportunity to change anything, he would have made a slightly larger version of the Spray. I have to make a clear decision on size, whether 31 or 36 ft. Having made this decision, I would like to talk out the steps to assemble the craft. Perhaps anyone interested in talking this one out could flesh out the problems with each step. Buy the plans from Brent. Buy the steel from closest source, sand-blasted, zinc primed, and delivered to a building site. Buy or rent a suitable welder, powered by a gas-powered generator. Buy sufficient quantity of epoxy to seal-coat interior, and exterior Buy diesel engine. Outfit inside and out. The problem of not having a place where the project can sit until finished needs to be dealt with at every stage. I would like to identify whether there are stages to which the task may be taken , and then the project may be stored to wait on better weather for a construction step, or for more funds. Are there storage facilities at a reasonable (read low) cost in the lower mainland? The next problem is, what are the best tools to do the job correctly, and should they be bought, or is renting the thing to do. What kind of trailer , heavy moving equipment should be at hand, etc. Solutions to both these problems depend greatly on fixing a time line for the project. I was amazed to see the construction of the boat proceed without a "strong back" , and to see assembled boats resting on the twin keels. I'm curious to know how the two halves are set together to be welded. What I've read about epoxies, is that they are temperature and humidity sensitive. How has this influenced the building schedules in coastal BC? From: Stephen Wandling Date: Sun Sep 9, 2001 8:46 pm Subject: Re: [origamiboats] picking up the thread I'm a construction Project Manager, so I understand your desire to have a plan before getting too far into a boat building project. I am currently finishing a steel hull (not origami, unfortunately) and have put some effort into developing a plan. I will insert my comments in your plan below: brib@axion.net wrote: I may be a few years from making a run at this, but I would like to clarify some of the logistics involved in carrying out a building program As I understand it, 31 feet is sufficient to cruise the world, even though I recall that Slocum with his slightly larger craft had mused that if he were allowed the opportunity to change anything, he would have made a slightly larger version of the Spray. I have to make a clear decision on size, whether 31 or 36 ft. Brent seems to have done a lot of his cruising as a singlehander. Crew size will be a requirement for selecting a boat size. Having made this decision, I would like to talk out the steps to assemble the craft. Perhaps anyone interested in talking this one out could flesh out the problems with each step. First I would recommend buying Brent's book, if you haven't already done so. Next might be site selection. A very desirable feature is having 220VAC with 50 Amps to power the welder. Buy the plans from Brent. Buy the steel from closest source, sand-blasted, zinc primed, and delivered to a building site. You might move this down a few steps, after you get your tools and welder lined up. Buy or rent a suitable welder, powered by a gas-powered generator. With 220VAC with 50 Amps to power the welder, you save a lot of bucks and noise without the generator. Buy sufficient quantity of epoxy to seal-coat interior, and exterior I don't have pre-primed steel so I have to interject sandblasting here and will have the same crews do the epoxy coating at it needs to go on within about 4 hours of achieving bare steel. It's recommended to put on one coat of your paint of choice over the last coat of epoxy, before the epoxy is completely cured. (It can be done later.) After the epoxy coating you will affix firring strips and bulkheads for the attachment of the interior. Then, it is common to have the hull insulated with urethane foam insulation. At this stage the boat is capable of sitting in the weather, either on land or in the water, for an indefinite period, if required. Buy diesel engine. I thought you were building a sailboat?!!? Just joking. I am one of those insane types that is building a boat without an engine. You will need the engine's mounting specs to enable properly building the engine mounts and associated shaft alignment. Outfit inside and out. With the bulkheads and firring strips, the interior is pretty straight forward. It's thinking ahead to all of the things that require cutting and welding in the hull, deck or cabin that have given me problems. You basically want all welding and cutting complete before you apply the epoxy coating. Like tanks, thru-hulls, portholes, cleats, stanchions, handrails, and the list goes on and on. The problem of not having a place where the project can sit until finished needs to be dealt with at every stage. I would like to identify whether there are stages to which the task may be taken , and then the project may be stored to wait on better weather for a construction step, or for more funds. Are there storage facilities at a reasonable (read low) cost in the lower mainland? My boat is now 'on the hard' in Richmond and I pay $150/month, but don't have access to 220VAC with 50 Amps to power the welder. My understanding is that when building in a residential area, it is often difficult to get a permit for a 'boat shed' but apparently you can build a boat "in the open" with no permit, at least in some municipalities. The next problem is, what are the best tools to do the job correctly, and should they be bought, or is renting the thing to do. What kind of trailer , heavy moving equipment should be at hand, etc. Most of these issues are well covered in Brent's book. Solutions to both these problems depend greatly on fixing a time line for the project. I was amazed to see the construction of the boat proceed without a "strong back" , and to see assembled boats resting on the twin keels. I'm curious to know how the two halves are set together to be welded. It's in the book. The simplicity of this method is the brilliance that Brent is bringing to the process of building steel boats. What I've read about epoxies, is that they are temperature and humidity sensitive. How has this influenced the building schedules in coastal BC? There are temperature and humidity criteria for epoxy coating, but I am informed that this work proceeds year round in the lower mainland. You might have to wait a bit if you get a cold spell. I will be watching this thread, because I still have issues that I haven't yet worked out. Good luck. Stephen From: darryl_marlene@h... Date: Mon Sep 10, 2001 5:34 am Subject: Finishing hull #1 from CCBB Hi everyone I read with interest most of the letters today. I`m in Nanaimo working on my 36 foot pilothouse . I hope to foam it Friday. If I can answer any questions on the benifits of having Confidence Custom Boat Building build your boat let me know. They did a great job on mine. If youre in my area I`ll gladly give you a boat tour. Darryl From: pvanderw@o... Date: Wed Sep 12, 2001 9:42 pm Subject: Re: picking up the thread > As I understand it, 31 feet is sufficient to cruise the world.. To get a feel for size, read the books by the Hiscocks and the Pardeys. The Hiscocks finally went to a larger steel boat which they had modified when 1/2 way around the world, as I remember. There once was a general notion, perhaps because of the Hiscocks, that the right size of boat for a couple was a little short of 30'. A larger boat required too much strength to handle the sails and too much maintenance. Equipment is better today on both accounts, but it is still a point to ponder. When you are getting down to a choice of a couple boats, ask the designer(s) pointed questions about the load carrying capacity, and do the math with rigorous honesty about what you expect to take and what you need in terms of consumable supplies. Capacity is more important that length, as a criterion. Peter From: cdbarry@h... Date: Fri Sep 14, 2001 2:07 am Subject: Size and other issues First, length is not the only measure of size, and certainly not cost or difficulty of construction. Increased size can make construction easier because spaces aren;t as tight. Setting principle dimensions is often the most difficult aspect of design and requires a great deal of thought and analysis. Commercial naval architects often do a series of "point designs" systematically varying dimensions to settle on the final parameters, but this decision is far and away the most important one and not to be taken lightly. Second, I can't say enough about the avantages of advanced/block outfit. Mr. Swain's notion of building systems complete prior to hull construction is a good approach to this. In fact it is possible to build substantial parts of the interior prior to hull construction, and then just load it in through the top of the steel hull (this is called "blue sky advanced outfitting"). The late Dale Calkins did a paper on advanced outfitting for small vessels that was in Journal of Ship Production a few years ago and Oetter, Duffty, Welter and myself published a paper at this year's Ship Production Symposium on advanced outfitting whole panels prior to joining them. Though this technique was based on developable panels, it should be adaptable to origami panels as well, with a little thought. From: "Doug Barnard" Date: Fri Sep 14, 2001 5:24 pm Subject: RE: [origamiboats] Size and other issues One point that wasn't brought up is market value. Adding a few extra feet when building is no big deal, but it can add thousands to the value of the finished boat. An under-30-foot boat sounds like an oddity, but on boats closer to 40', it sounds like a wise choice. As you're designing, it's always wise to imagine what the next owner might desire, and adjust your own preferences accordingly. I've finally got around to ordering a book that C.D. recommended, "Ship Production". It should be here by the weekend. I really like this idea about modular production. Trying to drag sheets of paneling down a narrow companionway doesn't sound like much fun. Though for those trying to build without the help of a shipyard, wouldn't the necessity of having a crane/gantry system outweigh the benefits? Also, what about areas in midspan of the seams? Might the steel not quite form according to computer predictions, and really throw off your developed bulkheads/soles? In answer to my own question, I can see that if you installed (dare I say it? :)) transverse frames at key points, where walls and floors hit, then matched up collars on the interior, that would be a handy thing. The way my design is working, it's turning into 3 long strips per side, instead of the "split orange peel" look of a pure Swain origami. It'd be much easier to take the offsets for the interior on a design of this type. I did a brief search for the articles that were mentioned above, but had no joy. Are there reprints available? From: "Alex & Kim Christie" Date: Fri Sep 14, 2001 8:09 pm Subject: modular drop-ins Due to the nature of the building technique, I think the shape of the Swain hull interior can vary a little beyond predictable parameters until you've fully fixed the deck on, so it might make it hard to prefab bulk-heads, which would have to be custom fit. Mind you, there are not that many bulkheads in a 36 foot boat, or boats on either side of that size range, right? But there is still a lot of stuff which can be pre-fabbed before the boat is even built, or during. It would be interesting to know if modular units have been done with deck off, however, as maybe I am wrong on that count. Anyone have any experience on this? Alex From: Stephen Wandling Date: Mon Sep 17, 2001 9:12 pm Subject: Vancouver BC Building Site? I have recently purchased a 35' Roberts steel hull that is lying at a yard without 220 VAC - 50 Amp power. The hull is and empty shell and I had intended on hiring a welder with a portable rig to complete the required work, but the failure of a construction Project Management contract to materialize is forcing me to consider other options. I am now considering moving the boat to a location with suitable power and buying a used stick welder and completing the welding myself. If anyone knows of a location with 220 VAC - 50 Amp power that is economical and/or is amenable to some form of barter, I would be very interested. The ideal location would be in the Greater Vancouver/Lower Mainland area. I can be reached at 604-649-1418 Thanks From: cdbarry@h... Date: Tue Sep 18, 2001 2:09 am Subject: Re: Size and other issues > I did a brief search for the articles that were mentioned above, > but had no joy. Are there reprints available? www.sname.org From: brentswain38@h... Date: Tue Sep 18, 2001 8:41 pm Subject: Re: picking up the thread The two halves are lined up at the bow and two points on the stem a measured distance down from the stem, near the waterline are tacked. The rest of the centreline is then pulled together with comealongs and tacked inside and out wherever possible, as you go. As you get to the weight bearing portion of the centre of the boat it gets more difficult. Jacking up the chines helps, as does rocking the hull back , pulling together the part which has lifted off the ground then rocking the boat foreward onto the tacked together part and continueing. To stop the plates from overriding one another at the stern it's neccessary to tack a piece of flat bar to the centreline on each of the halves to prevent the override . They can be broken off after the centreline is together. We try to do our epoxy painting in the summer. If you've got your steel work completed and it's winter, you can still make progress by pre fabricating the interior. Having the plate still in the primer stage lets you weld your interior attachment tabs where you need them.Tabs the size of your hand are just as good for attaching interiors as transverse frames and are less time consuming and less of a liability if you hit a reef. When painting weather arrives you remove your interior parts , putting the bigger ones under the cockpit while you paint up foreward. Then you move them foreward while you paint aft. I just received a copy of the metal boat quarterly from the metal boat society. They mention a place in Hadlock Washington which has surplus devoe bar rust 235 epoxy for $50 US for a 5 gallon pail. The same pail in Canada is $350 CDN.I've been told that they also have a lot of primers and antifouling, cheap. Brent Swain From: "Richard Till" Date: Tue Sep 18, 2001 11:03 pm Subject: Re: Surplus paint I have been in touch with D&R Surplus in Port Hadlock. They are presently out of Ameron Devoe Bar-rust 235. They have limited stock of another 2 part epoxy at the moment. Looks like the painting season on the BC coast may be over for this year anyway? Busy with detail work and dumpster diving for more stainless pipe. rt From: cdbarry@h... Date: Wed Sep 19, 2001 1:00 pm Subject: Re: Size and other issues --- In origamiboats@y..., cdbarry@h... wrote: > > I did a brief search for the articles that were mentioned above, > > but had no joy. Are there reprints available? > www.sname.org Also www.nsnet.com, then look under the documentation center. From: robertgm77@e... Date: Thu Sep 20, 2001 4:10 pm Subject: Re: Surplus paint >Look for expoxy paint from the industrial suppliers such as people who paint oil tanks at refineries.It is cheap but will be basic colors. From: rct_51@h... Date: Fri Sep 21, 2001 12:30 am Subject: Re: scrap/salvage/usefull boat stuffs For what it's worth: there is a place called "The Bitter End Boaters Exchange" in Gibsons BC. The place is run by Garry White. I have the leading edge for a fin keel (1/2 a piece of sch 40, 6") if it is of any use and enough 1/2" plate to do the sole of a keel. rt From: cdbarry@h... Date: Fri Sep 21, 2001 3:08 pm Subject: Society of Boat and Yacht Designers Meeting To all SBYD members and friends, The second meeting of the SBYD, Chesapeake Chapter for this year will be held in the Dodson House conference room of the Chesapeake Bay Maritime Museum, 6 October 2001. We will be meeting during the Mid-Atlantic Small Craft Festival, which is held every year during the first weekend in October at the CBMM. Mr. J.B. Currell of MAAS Plastics will share his thoughts on wood/epoxy construction and fiber reinforced epoxy composites. The meeting will begin around 1000 hrs. and should end around 1400 hrs. After the meeting attendees are encouraged to visit the MASCF on the museum grounds. Copies of the minutes from the previous meeting will be available for review and approval at the meeting (if not before via e-mail). See the included map below for location. Respectfully, Nathan R. Fuller, Jr. Secretary, SBYD Chesapeake Chapter phone: 1-703-532-0044 e-mail: 73314.104@c... postal: 6444 Queen Anne Terrace, Falls Church, Va. 22044-1417 USA From: brentswain38@h... Date: Fri Sep 21, 2001 7:16 pm Subject: Re: scrap/salvage/usefull boat stuffs For the leading edge of a fin keel, if you use sch 40 you'd be wise to double it up. Even with lead poured behind it sch 40 will dent if you hit a reef at full speed . Sch 80 (1/2 inch wall thickness)doesn't dent no matter how hard you hit. Brent Swain From: Stephen Wandling Date: Fri Sep 21, 2001 8:46 pm Subject: Re: [origamiboats] Re: scrap/salvage/usefull boat stuffs Brent, I am trying to adapt some of the design details from your excellent book into the Roberts I am completing. I am removing the skeg/spade rudder assembly and installing a low aspect skeg with an outboard rudder. It's hard to determine some of the required detail from your book and I am wondering if I might benefit from buying a set of plans, if they contain the additional detail. For example, do you recommend sch 80 pipe as the leading edge of the skeg? What diameter (it looks to be about 1 1/2" in the picture?)? The upper portion of the pipe looks to extend maybe 18" above the skeg. Is it intended to insert all of this into the hull, and if so, how is it dealt with on the inside (gussets, etc)? Is the skeg plated with 3/16"? The max width of the skeg at the hull connection appears to be maybe 3 1/2", is this about right or is more better (I know more is stronger, but I am assuming that if the skeg is too 'fat' it might reduce performance)? I could ask similar questions about the anchor winch, rudder, etc. Would a set of plans for one of your boats contain the detail that I am looking for? Thanks for all of your help Brent. Stephen From: "Alex & Kim Christie" Date: Fri Sep 21, 2001 8:59 pm Subject: photo of Swain 36 being trailered If anyone was ever curious how the twin keeled Swain hulls are best transported by road, I'd suggest having a look at these photos, which show what I surmise to be a 36 footer in transit by Don's Transport of Victoria, BC. The trailer is basically a low-deck flat deck, and the hull is well strapped down. These are "spy" shots, taken several days ago with digital camera through the windshield of my Van at 70 Kilometres/hr, so might be a little fuzzy! I'll put these photos in the group's photo section for those who only recieve daily digests which don't have attachments. Alex Christie From: "Alex Christie" Date: Fri Sep 21, 2001 9:08 pm Subject: Re: photo of Swain 36 being trailered I should add that the vessel is called "What Is", of Port Alberni. Anyone know the owner? Also interesting is that the owner has not installed an inboard, but has chosen to have what looks to be a longshaft outboard in a well. There is one of those rings around the prop for added thrust, in the manner of a Kort Nozzle, but on a smaller scale. Alex Christie From: "brent swain" Date: Sat Sep 22, 2001 8:55 pm Subject: Re: [origamiboats] Re: scrap/salvage/usefull boat stuffs ABC salvage just off SE marine drive in Burnaby has always been a great souce of scrap. They mangle the hell out of everything, but they always have lots of stuff. Brent Swain From: "Richard Till" Date: Mon Sep 24, 2001 8:29 pm Subject: Re: [origamiboats] Re: scrap/salvage/usefull boat stuffs Brent, I agree. On closer examination, i did order Sch. 80, 6". This should match the 1/2" sole plate in wall thickness. Just measured it to make sure and it all matches up. rt From: wade panzich Date: Wed Sep 26, 2001 9:46 pm Subject: Re: [origamiboats] scrap/salvage/usefull boat stuffs Whats up sucka, I hope all is going well for you down there just wanted to say hello and wish you luck with everything, got my engine done I just need to put it in, I cant find anyone to help me, everyone is gone. All is great here, the weather has been good and saw some lights last night. Keep in touch I may be down there sometime I will keep you posted, Aloha bro Wade From: evanmoonjunk@y... Date: Wed Sep 26, 2001 11:43 pm Subject: Re: photo of Swain 36 being trailered --- In origamiboats@y..., "Alex Christie" wrote: > I should add that the vessel is called "What Is", of Port Alberni. > Anyone know the owner? > Hi Alex, yes this is a boat that I pulled together about ten years ago in Port Alberni. The owner is Toni Janske(spelling unsure} He wanted a boat just under 30' so he could ship it to Europe on a freighter and also wanted a flush deck for max. interior space. We put in an outboard well cause he did not want to use interior space for an inboard. He seems to be happy with the boat but it has been several years since I talked to him. Apparently he trucked the boat over to Nanaimo so he would not have to sail around. Probably does not have a whole lot of time off....Evan From: "brent swain" Date: Thu Sep 27, 2001 12:46 am Subject: Re: [origamiboats] Re: photo of Swain 36 being trailered Evan I just had a look at Rob's boat in Cortenay. Nice workmanship. While I was comming home from Tonga, I found that the intake thru hull on my head was comming out of the water when the boat heeled in gusts and I had to wait for the lulls and pump like hell to get rinse water into the head before the next gus came. I've since moved the intake much closer to the centreline.Bill Lornie had to move the intake for his exhaust cooling almost all the way to the centreline to stop it from sucking air when he heeled or was in rough water. Rob's head intakes would have been out of the water anytime the boat heeled more than ten degrees. When offshore cruising , you can be heeled 25 degrees for weeks on end. I told him to move them nearer the centreline. Lately I've been putting in a stainless doughnut around the exhaust outlet , flush with the hull plate,as the heat from the exhaust burns the hull paint around the exhaust thru hull and you get a serious corrosion problem there after a few years, even with a wet exhaust . The aft keel stifners should be tied together with an angle iron floor of heavy angle (3 inch by 3 inch by 1/2 inch),triangulating the trailing edges of the keels with the centreline , otherwise a hard collision with a rock will drive the trailing edge of the keel up into the hull a couple of inches . I learned this the hard way, and had to jack the keel down with a hydraulic jack before welding in the angle iron floor. I just missed you here in Comox by a couple of days according to Karl.I may be through Nanaimo tomorrow some time. Brent Swain From: rct_51@h... Date: Fri Sep 28, 2001 9:14 pm Subject: Re: scrap/salvage/usefull boat stuffs Another place to check: Mariners Xchange, 12220, 2nd Ave Steveston, Richmond BC. Phone (604)271-2284. On another topic: Over time, I have developed a very low tolerance to diesel fumes of any kind. Can anyone comment on effectiveness and efficiency of an outboard. I have seen them rigged in wells, brackets on rudders etc. I notice that, in general, wells seem to circulate fumes back into the cockpit. I have a Honda on my CAL 25 right now--it runs like a clock under most conditions. An x US Coast Gaurd officer (tourist) asked to see the construction of the (36')steel boat the other day and commented that a 10 hp Yamaha high thrust outboard (when compared to an inboard) delivers the equivalent of 35 hp at the prop? Brainstorming--any thoughts would be welcome. rt From: "Dale J. Robertson" Date: Fri Sep 28, 2001 9:29 pm Subject: Looking for a yard to build a hull Is anyone aware of a steel boatbuilder on the east coast (preferably in the D.C. -Annapolis area) TIA Dale J. Robertson From: "John P Barker" Date: Sat Sep 29, 2001 6:59 am Subject: Re: [origamiboats] Re: scrap/salvage/usefull boat stuffs An x US Coast Gaurd officer (tourist) asked to see the construction of the (36')steel boat the other day and commented that a 10 hp Yamaha high thrust outboard (when compared to an inboard) delivers the equivalent of 35 hp at the prop? I was going to say something very rude about our CG but I will limit my self to saying NO WAY!!! It will push your boat but lacks the power to stop it quickly. Another thing to think about is your electric generation requirements out board motors are usually week in this department. John From: "Alex & Kim Christie" Date: Sat Sep 29, 2001 8:18 pm Subject: Outboards for motive power People will almost universally agree that a nice slow turning diesel with properly matched propellor and reduction gear are a nice way to go. But if you can't afford such an installation, there are some remarkable new outboard products out there which will suffice, and then some. My thoughts on outboard motors, having used them on a heavy boat in a pinch, then finding them to work remarkably well: I think it works better than people will admit, but it is important to recognize that not all outboards are equal. My Honda 7.5 hp did sterling service with a special aftermarket low-pitched "elebhant ear" prop, which I used in tandem with a 15 hp Suzuki 15 hp with low pitch prop. The Honda alone could push the boat fine in calm, the two together were needed in chop or headwind. My recent forays to the Honda dealer in Campbell River revealed that they now have a high-thrust version in their outboard lines which have 2:1 reduction gears in their hubs, similar to the Yamaha line, and very large "lobed" propellors. Starting with a machine like this will at least give you the most possible thrust out of a given engine. It is true that the ability to back up quickly was hampered, but I soon developed a fail-safe strategy: I would simply back in slowly to the slip, saving the powerful forward thrust for stopping the boat, which it did rather smartly. My two regular outboards were very good at this, and I can bet that a proper 2:1 hub outboard with lobed prop would be even better. It may be possible that actual measurement of pulling power ("bollard pull") of a Honda or Yamaha high-thrust 2:1 hub outboard could be equivalent to a 35 hp with regular high speed prop, since the 35's prop would be slipping alot while trying to move a heavy weight from a stand-still. But a 35 hp with low-pitch pulling prop might beat it by some degree. It is the 2:1 reduction in the high-thrust motors which makes all the difference, and this coupled with a proper pulling prop can present quite a formidable force. It should in theory double the pulling power of the 10 hp. Nothing beats going out there and trying it out, and I was as surprised as anyone to feel the "muscle" of my puny 7.5 Honda accellerating my heavy 36 footer from full stop to a reasonable cruising speed in short order. It is all in the pitching of the prop, the size of the prop blades, and ideally the gearing of the hub (which, though I did not have, would have only been an improvement.). Say: as an experiment, if someone in my area has a 10 hp high-thrust, then put it on a boat and bring it over to my place where I have a Honda 35 on a runabout, and we'll have a tug of war to see which can pull the best! As for electricity generation, perhaps the new Honda generator line which has come out might work. They are very small, but very efficient of fuel with high output. Regards, Alex Christie From: "Alex & Kim Christie" Date: Sat Sep 29, 2001 8:22 pm Subject: electric drive Electric drive may be an option worth considering, as you can use the same motor to generate electricity while under sail. It can work both ways in an on-off mode, according to the literature for the Electric Wheel (Solomon Technologies). This means while you are motorsailing the drive can be pushing you up a wave, but generating electricity going down a wave, or when sail power overtakes the drive in terms of thrust transmitting to the hull. http://www.solomontechnologies.com/ offers the Electric Wheel Alex Christie From: Richard Payne Date: Sun Sep 30, 2001 10:40 am Subject: Re: [origamiboats] electric drive I had an electric vehicle for some time - it was a little Mazda van with 96 volts dc in wet cells. It used an advanced transistorized scr speed control and would get up to 60 MPH for short bursts. The best thing was that I could recharge it at work and drive for nearly free! Unfortunately ,the achilles heel was the battery technology. The life of the batteries is not economic and for that reason I would suggest you give the electric idea a miss - once you work out the number of cycles and the cost of the batteries you will see that whilst it sounds good it is an expensive way to go until we have more advanced battery technology, which is a real pity. Regards, Richard Payne. From: "Alex & Kim Christie" Date: Sun Sep 30, 2001 5:17 pm Subject: Re: [origamiboats] electric drive I guess the other hope is the promising developments in the Ballard Fuel cells, which could provide a clean, vibration-free source of energy. I note also on the www.solomontechnologies.com website that most installations have a Panda 4kw generator for recharging. While this may be a step backward to internal combustion technology, it does allow one to isolate sound and vibration with a machine which should have long life. With a generator, solar panels, wind turbines, and drag generation through the prop, you could certainly have a crack at saving enough fuel to pay for the unit over its lifetime, or at least make the battery replacement issue a little less harsh. Alex Christie From: rct_51@h... Date: Mon Oct 1, 2001 7:07 pm Subject: Re: electric drive and outboards Thank you for the brainstorming. Solomon technologies has an impressive solution, albeit with an expensive capital outlay. I once towed a large Grand Banks from Vancouver Bay to Egmont with a 10hp outboard on a skiff against the wind. They had run out of diesel and the wind was pushing them up on the rocks. Also towed a dive boat (out of fuel) from Spanish banks to Burrard Civic with the 7.5 Honda on my Cal 25. This seems to indicate that the thrust can do the job. Tug-o-war would qive a quantifiable result. The weakness appears to be in attaching the motor to the hull. An inboard has more structural integrity in so many ways. Still thinking, rt From: fprice@i... Date: Tue Oct 2, 2001 5:32 am Subject: Re: [origamiboats] Re: electric drive and outboards Hello Guys There has been a recent article in "Cruising World" magazine detailing the setup of an outboard on the quarter of an Alberg 30 yacht. Thie setup detailed was way the best solution to using an outboard that I've ever seen, enabling the engine to be postioned so that the quarter wave didn't drown it, and that following seas also had "less of a chance" of killing it. In the up position it was right up at the rail out of the way except maybe if you were lying alongside a wharf (what you call a non floating piled dock?) The other advantage I see in this solution over a well is that it allows a reasonably big engine to be used without the overheating/air supply problens that wells often seem to give. The article is at home but if anyone is interested I can scan and post it. Regards Foster Price Southland, New Zealand From: "brent swain" Date: Tue Oct 2, 2001 7:46 pm Subject: Re: [origamiboats] Re: scrap/salvage/usefull boat stuffs Fishermen have come up with a simple solution to diesel fumes, install a couple of large electric fans hooked up to the ignition switch, one to pump a large amount of air in and another to pump it out. Then make the engine compartment as airtight as possible from the inside of the boat. That should be easy to plan if you start in the building stage. Outboards can work well, but I'd still weld in diesel engine mounts , stern tube, and exhaust outlet in the building stages to leave your options open. Making your mounts low and wide enables you to use any engine that comes along. Making them too high and narrow limits your options.Potential fuel tanks can start their life as water tanks. On my last boat the new owner trashed the diesel by overloading it. There was a steel boarding ladder on the side, connected to the bulwark cap by welded on chain links. He mounted the outboard on the boarding ladder and put a large scotchman under it to act as a float. When a wave came along , rather than submerging the outboard, it floated over the waves with the help of the scotchman. I've been told that extensions for a Johnson outboard fit into one another and you can put together as many as you want to make as long a shaft as you want Brent Swain From: "Alex & Kim Christie" Date: Tue Oct 2, 2001 9:04 pm Subject: diesel outboard from China Diesel Here is an outboard from China Diesel which is designed for pushing big boats. $995 U.S.! I wonder if it could be fitted with a really long shaft? Currently 41" from bottom of unit to motor mount, longer than the longest longshaft outboard. 'Tain't a lightweight, at 250 lbs, but interesting to ponder if it could be rigged up right. I assume it is made in China, which would bother my conscience if I were to buy, considering their oppressive stand on Tibet... http://www.chinadiesel.com/mrn/diesel_outboard.htm Alex From: "Doug Barnard" Date: Wed Oct 3, 2001 12:46 am Subject: RE: [origamiboats] diesel outboard from China Diesel And with most teak coming in from Myanmar (Burma), what's a boatbuilder to do? :( From: brentswain38@h... Date: Thu Oct 4, 2001 11:26 pm Subject: Re: diesel outboard from China Diesel Use any other wood but teak. Teak inside a boat tends to make the interior look like a cave during overcast weather, and using wood on the outside of a steel boat is a big mistake. I used to use salvaged gumwood from motorcycle crates , but now they are mostly made of metal. Gumwood is much better than teak for corners as it takes a lot more abuse. Brent Swain From: cdbarry@h... Date: Mon Oct 8, 2001 7:56 pm Subject: Re: Outboards for motive power The calculations are fairly simple to do to compare thrust, etc. and would tell the story. The current 3 volume PNA has data for B series and Kort nozzles, and segmental data is available from the Blount- Hubble 1981 paper (www.sname.org) I have spreadsheets for B-series, segmental props and Kort 19A nozzles in Excel, using these references. If you want me to do a specific check, let me know with speed, etc., or I can send you the sheets. From: cdbarry@h... Date: Mon Oct 8, 2001 8:01 pm Subject: Fuel Cells The Coast Guard is currently using fuel cells to power some lights in Alaska. MTU also has a program going for marine fuels cells for marine propulsion. From: evanmoonjunk@y... Date: Fri Oct 12, 2001 9:08 pm Subject: Re: photo of Swain 36 being trailered Hi Brent, Thanks for the feedback. Somehow I missed your message the last few times I checked the forum. The deal with Rob is that he has had years of experience as a fisherman and had his mind made up about some ideas on his new boat. I tried to convince him to change his mind about a few things on the boat but without success. At the time he was happy as he got what he wanted. There is always a lot of discussion of ideas whenever I build a boat for a customer. I always tell people what you recomend as well as telling them what others have done, and then help them decide what they would be happy with. but the final choice is theirs(within reason!)...Evan From: rct_51@h... Date: Wed Oct 24, 2001 3:19 am Subject: Interesting experiment with UHMW plastic Local industries use Ultra High Molecular Wheight plastic for flights on conveyors, wear plates in chutes, bearings and bearing surfaces, etc. Someone described its' performance as "nylon on steroids." Nevertheless, it does eventually wear in extermely abrasive environments. When it gets worn into irregular shapes it often gets discarded. The good news is: you can shape it with woodworking tools. Having welded nylon with good success in the past, i surmised this stuff would join just as well--it does. I took (2) 1.5" slabs and welded them together to make 3" wide bow rollers out of. I tested the weld with a blacksmith hammer--the joint is rock solid. To weld the stuff: drill holes in roller pieces; heat both surfaces of roller pieces with propane torch until clear liquid plastic appears in an even film; place on threaded rod quickly with the two liquid surfaces facing; tighten nuts on ready rod. This ensures even pressure and symetry. I used the same size rod to do this as to turn down the rollers. The trick is to rehearse everything before you actually do the weld. I plan to make more rollers this weekend for spares. rt From: normkoenig@y... Date: Sun Oct 28, 2001 2:15 pm Subject: Specs on Brent's designs Group, I just stumbled onto this group and am fascinated by Brent's designs. I have a few questions, though: Are there non-pilothouse versions available? Is there standing headroom in such designs in the 31 and 36 foot version? How much? Does anybody have any drawings with sample interior layouts? Are specs available for the 31 and 36 footers? Thanks in advance for your help. - Norm From: Stephen Wandling Date: Sun Oct 28, 2001 6:37 pm Subject: Re: [origamiboats] Specs on Brent's designs Norm, I am sure Brent will be along shortly and will provide answers to your questions, or you can email him directly at . I didn't discover Brent's boats until after I had purchased a 35' Roberts designed steel boat, or I probably would be building a Swain boat right now. I want to make a comment on pilothouses. I confess to having a prejudice against 'wheelhouses or pilothouses'. "Real men man the helm in the wind and rain" and all of that good stuff. I had hoped to have my boat in the water by now, but circumstances have deemed otherwise. I am glad. Given the onset of the new season and a few samplings of the season to come, I am realizing that if I intend to make this boat my full time home I will have to have a 'full time' view of the weather conditions to be expected. The long and short of it is that I will now add a minimal pilothouse to my boat, enabling me to have a look around from inside while the vane steers it's course. Since I won't have an engine I won't be making the typical use of the pilothouse: motoring, but by running a morse cable from inside, connected to the trim tab on the rudder I can have steering with a 'jog stick'. If I want to actually sail from inside, this will also require running the halyards from the two junk sails and their sheets inside as well, as well as a Plexiglas 'skylight' panel to enable observing the main sail's set. But, most of the time I will let the vane do the steering. [This reminds me that I have not yet resolved how to run the halyards, etc. into the pilothouse and still allow their manipulation from the cockpit, in a manner that will not result in water leaking in to the pilothouse space. I guess I could have them channeled in a 'trough', running fore and aft and without a top, that has a drain. But issues on shifting from cockpit to pilothouse and back are still there. Any ideas?] I will confess to being well into the second half of my first century on the planet, which I suspect may have some impact on my pilothouse decision! Cheers, Stephen From: evanmoonjunk@y... Date: Thu Nov 1, 2001 12:53 am Subject: Re: Specs on Brent's designs Hi Norm, These boats have built with pilot houses, without pilot houses, normal cocpits, no cockpits(flush deck in stern) raised flush deck in back and variations of this. I have done all of the above as well as a 30' with a raised flush main cabin. There is no problem getting lots of headroom as the cabin floor can be installed according to the headroom you require Brent has some sample interiors in his plans, you would have to contact him to get copies.As far as specs are concerned, those are in the plans as well, if there is anything specific you would like to know, you can e-mail either myself or Brent...Evan From: robertgm77@e... Date: Sun Nov 4, 2001 9:17 pm Subject: bilge keels or not ? I recently met some people who were on a bilge keel boat that ran aground. All usual methods of getting oneself off,kedging,pulling the mast over etc only dug the keel deeper on the side they worked on. They had to get towed and the boat had minimal damage.Has anyone had this experience ? I am considering one keel design or the other and trying to evaluate the pros and cons of both. From: Russ Ashworth Date: Mon Nov 5, 2001 4:01 am Subject: Re: [origamiboats] bilge keels or not ? If the boat is sailing and healing when you hit the lee keel will be anything up to a foot or more deeper than usual, and releasing the sail will allow the boat to come upright thus reducing the draft. The way to get a bilge or twin keeler off is to get it upright. Or put the kettle on and wait until the tide comes in. That is the way they do it in England.:) Check out the following for some fascinating reading. http://www.brayyachtdesign.bc.ca/html/twinkeels.html http://www.brayyachtdesign.bc.ca/html/blgekeel.html BTW. I have just bought an English Twin Keeler. It is an amazing little boat. Russ Ashworth An oar will always start first pull. From: "Alex Christie" Date: Wed Nov 7, 2001 5:51 am Subject: New cover photo showing bilge keels Greetings, You'll notice I changed the home page photo; this is a boat I took a snapshot of last summer while in Vancouver. Didn't see a name on it. Anyone know it? Anyhow, thought I'd post it as it shows very nicely the shape and positioning of the bilge keels that have been the subject of discussion lately. Alex Christie From: brentswain38@h... Date: Wed Nov 7, 2001 8:35 pm Subject: Re: Specs on Brent's designs I can't imagine why you'd want to sit in the driving rain in an open cockpit in raingear, just to look stylishly foolish, when you could be in a pilothouse , warm and dry in a t shirt sipping on a hot chocolate reading dry charts. both the 36 and 31 footers have lots of headroom. If you dropped the floor of the 36 as far as it can go you'd have almost 7 foot headroom in the trunk cabin and 8 ft in the wheelhouse. We usually go for 6ft 2 inch headroom and make the bilge into tankage. The 36 is 35 ft 5 inches overall, 29 ft waterline, 5ft 10 inch draft with the fin keel, 4ft draft with the twin keels , 17,280 lbs empty, full depends on how much of a packrat one is. 5700 lbs keel weight,(4500 lbs lead ballast, 1200 steel ) Most people go for a 46 or 47 ft mast stepped on deck. The 31 footer is 31 ft overall, 26 ft waterline, 3500 lbs lead ballast , 4500 lbs total keel weight, 4ft draft twin keels , 4ft 6 inch draft single long fin keel . Most people go for a 40 ft mast stepped on deck . Both boats have 3/16th inch hull plate , 1/8th inch deck, cabin cockpit and rudder plate, 1/4 inch keel plate and 1/2 inch on the bottom of the keel. Altho I've built a 36 ft hull in ideal conditions, and shell ( hull deck cabin cockpit , keels, skeg tacked together in 6 days, it usually takes 2 to 3 weeks . Morse cable on the trimtab works well for inside steering, but lately I've been using a shaft run from the transom under the deck with an arm sticking up linked to the trimtab and an arm inside sticking down linked to the jogstick. Morse cable can corrode and sieze up, and it's travel distance is limited. The solid stainless shaft will last forever and you can give it whatever travel you need. Brent Swain From: brentswain38@h... Date: Wed Nov 7, 2001 8:49 pm Subject: Re: bilge keels or not ? The last thing you want to do in a bilge keeler is run aground at absolute high tide. I did once and had to dig myself out. By the time I did the lagoon had frozen over and I had to ram my way through a quarter mile of five inch ice. Most people who have built my twin keelers wouldn't want anything else and most of those who hav built single keelers wish they had twin keels. Jack Carson sailed one of my 36 foot twin keelers around the world, then built himself another twin keeler. He said that he was able to get into a lot of remote places and hang out in river mouths where the single keelers can't go . He said that for the whole east coast of Australia a twin keeler can hang out in quiet waters in drying anchorages while the single keelers bounce in the swell outside. Twin keelers are slightly slower upwind than a single keeler, but the differece is very marginal . One of my 36 ft twin keelers just sailed from Sooke to San Francisco in 5 1/2 days . I sailed from Sooke BC to Ensenada in 14 days , and just sailed home from Tonga to BC , to windward for all but the last 1,000 miles . I sailed from Hilo to BC in 23 days, in spite of making absolutly no easting against 20 knot NE winds until 38 north . Twin keelers don't have the tankage in the keels that single keelers have. My current 31 ft twinkeeler has never paid to stay in a marina in the 17 years since I launched her , largely due to her ability to dry out. Brent Swain From: brentswain38@h... Date: Wed Nov 7, 2001 8:54 pm Subject: Re: bilge keels or not ? If you get stuck on a falling tide,in a twin keeler, relax, put the coffee pot on and enjoy the break. Some twin keelers often pull into an anchorage at night and deliberatly hit the beach, put out a lot of anchor rode and go to bed , with no worries about dragging anchor . When a gale blows through an anchorage there is no place I'd rather be than hard aground. Brent Swain From: "Mike Tracy" Date: Thu Nov 8, 2001 12:14 am Subject: Re: [origamiboats] Re: Specs on Brent's designs Brent, How's the headroom and draft on the 26 footer? Mike From: "Alex Christie" Date: Thu Nov 8, 2001 6:04 pm Subject: Kobella - a 36 footer For new members to the group, I have posted photos of Kobella in the photo section. This is a fine 36 footer located on the British Columbia coast. I think it is a good example of the type, and the photos show some details that are typical hallmarks of Swain boats. These are: "ship"-style main cabin hatch, owner-built manual anchor winch, pilot house and more. What sets these boats apart from other is that the plans and the book provide details for constructing nearly everything on the boat, obviating the need to purchase expense "marine" parts of dubious quality. I think Brent has dealt very well with the age-old adage:"The most important piece of equipment will always fail when you need it the most", and has engineered the accessories to deal with the worst conditions one typically meets. There is a lot of store-bought equipment out there which is only designed to look pretty and function on a shelf in a marine store. Alex Christie From: paull01@y... Date: Sun Nov 11, 2001 7:25 pm Subject: Email Onboard Brent, I was curious about your email setup. You said you've been living aboard with very little need for expense. I was wondering how you communicate with email. Do you use an HF setup? Do you have to go through an ISP? Paul Woodinville,WA From: "Alex Christie" Date: Mon Nov 12, 2001 1:58 am Subject: Origamiboats group: 6 New photo albums Dear Group, For the benefit of new members, I have added six new albums of photos to the Photo section. Some of the albums are a repeat of those in the old Files section, re-created in the Photo section for ease of viewing with thumbnails. Of particular interest to everyone may be the "Building Sequence" photo album, which I have re-organized to follow the actual lay-out and building sequence of a typical 36 footer, from plate as delivered to basic hull (sans keels and skeg). The views which follow most logically are the "Paul's boat" photo file, which shows a hull in one piece before painting. Also added are snapshots of Brent Swain's own 31 footer, and the newest 40 footer (there are two now) in the South Pacific. The Dove III album shows the 26 footer built on Vancouver Island and sailed through the Canadian Arctic Northwest Passage (there is a great book available about this exploit). The new home page photo shows designer Brent Swain's 31 footer standing proud on a drying mudflat. The twin bilge keels and skeg assure a steady footing. It is great to see more people joining the group every day (about 5 a day now). Please feel free to post any questions and thoughts you may have to the group any time. Alex Christie From: winslow59@y... Date: Wed Nov 14, 2001 8:17 pm Subject: MBQ & Brent Swain -- plus META The current issue of the Metal Boat Quarterly (vol.14 - no.4) has an article by Brent Swain titled, "Origami Boatbuilding" -- includes six fotos. Metal Boat Society: http://www.metalboatsociety.com/mbs/index.php -- also -- Marc Bouriche, of the French shipyard META, submitted an interesting article about their Strongall building process ("...use of extra thick aluminum plates to make a stressed skin - without the classical skeleton of ribs and rib-bands, double chine hull) and the aluminum hull anti-corrosion product, Inversalu. META http://www.reducostall.com I would be interested in learning more about the META sailboats -- and reading personal experiences and opinions. From: "Doug Barnard" Date: Thu Nov 15, 2001 12:10 am Subject: RE: [origamiboats] MBQ & Brent Swain -- plus META I believe that you have to be a member to get into the section on the current issue... From: "Gary H. Lucas" Date: Thu Nov 15, 2001 12:28 am Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META Doug, What are you using to design your boat? I have done some playing with Rhino and was able to create developable plates in 3d that I then cut out of paper and assembled. Gary H. Lucas From: Doug Lind Date: Thu Nov 15, 2001 12:51 am Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META I was thinking of buying a hull from Winfield (Brent Swain design) made out of aluminum but after reading someof these threads I an now considering steel. I am only part way through. I am not much of a welder so I am looking at an already built hull. I have just ordered Brent Swain's book so I will take it from there. Thank you Doug From: "Gary H. Lucas" Date: Thu Nov 15, 2001 1:25 am Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META Doug, You mentioned 48'. Brent only has designs to 36', which is why I asked. Gary H. Lucas From: Doug Lind Date: Thu Nov 15, 2001 1:56 am Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META If you follow the thread down there is a different Doug a Doug Barnard From: "Gary H. Lucas" Date: Thu Nov 15, 2001 2:01 pm Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META Sorry about that! So what is leaning you towards steel? I work in aluminum every day, for machinery that needs to be light and corrosion resistant, in the commercial greenhouse industry. After owning several fiberglass boats I've always wanted an aluminum boat, despite such issues as electrolysis. Gary H. Lucas From: "Doug Barnard" Date: Thu Nov 15, 2001 6:46 pm Subject: origami trawler (was MBQ & Brent...) Here I am! I, too, am using Rhino 2 to get my developable plates. I'm just about ready to try the first printout at 1/2" = 1 foot scale. The actual hull design is the 48' LRC from Charles Wittholz. By taking the table of offsets from any design, you can (hopefully) convert it to an origami boat. Once I get this model completed, I'll do the deck house as well, all of the parts that I'd have CNC cut. The one problem that I'm having is to make the bow plates concave. I'm assuming that once the hull is welded up, the bow can be pulled in with come-alongs to form against the crash bulkhead (which has curved edges), just aft of the chain locker. Sound right? I'm thinking about writing a little tutorial on how I converted my offsets, for public perusal in the origamiboats library. Would there be interest in this? From: jmatt@e... Date: Fri Nov 16, 2001 1:52 am Subject: Re: [origamiboats] origami trawler (was MBQ & Brent...) It would be very helpful. Begining Rhino student here. JM From: "Alex & Kim Christie" Date: Thu Nov 15, 2001 7:08 pm Subject: converting offsets to origami templates Doug, Your project sounds very interesting, especially the aspect of converting any table of offsets to origami-style building. I'd guess that after trying it with the real steel that there would be some aspects of steel behaviour that are hard to predict, but this information could be fed back into the design for improvement. By all means feel free to put something in the files about it! Alex Christie From: "Alex & Kim Christie" Date: Thu Nov 15, 2001 7:09 pm Subject: Rhino URL? Doug, can you send URL for Rhino for us all to check out? From: "Doug Barnard" Date: Thu Nov 15, 2001 10:23 pm Subject: RE: [origamiboats] Rhino URL? > Doug, can you send URL for Rhino for us all to check out? http://www.rhino3d.com/ DB From: "Doug Barnard" Date: Thu Nov 15, 2001 10:23 pm Subject: RE: [origamiboats] converting offsets to origami templates Well, here's the reader's Digest condensed version- it may take me a while to get the full tutorial done. So far, the only type of surface that I've found that can take advantage of the "Unroll Developable Surface" command is a "Sweep 2 Rails". This requires longitudinal lines, like the chine and the sheer, and a *straight* line that sweeps along them. The two rails can be a "Curve: Interpolate Points", which allows for the control knots to be right on the vertices. This makes for smooth longitudinal lines that pass though exact coordinates. So you grab the Table of Offsets of the source design, and begin inputting. The way that I do this is to make a square that has one corner at 0,0 and the other corner at the measurements called for in the offsets. I draw a series of squares for each station, then draw *separate* Polylines that snap to the corners of the squares. Once I have my transverse profile polylines, I then move them into position along the longitudinal axis according to the distance that the station is from the datum point. So station 0 is at zero, station 1 moves in 2'6", or whatever. You go through the entire table, making your ribs and moving them into position. So now your have something that looks like half of a boat. Making sure that your Osnap is turned on to End (points), draw a continuous Curve: Interpolate Points that snaps to each of the transverse vertices. Select the line segment at station 0, and Sweep 2 Rails. After you have done this for all of the longitudnals, you can select the surface strips and Unroll Developable Surface. These strips can be saved as .dwg (AutoCAD drawing), and taken into AutoCAD to be plotted to the scale of your fancy. Then, using a spray adhesive like Scotch 99, and working outside, attach the printout to poster board and cut out with an X-Acto, or whatever. Does this make sense? Anyone feel free to ask questions. One problem that I've had is in the line to swept. Let's say that you want to make a boat with a curved transom. Even though the line is curved in a way that's parallel to the surface, and the surface should "see" it as a straight line, I can't seem to unroll the resultant surface. Maybe somebody else might have better luck than I at this; if so, please share! Also, there are gaps between the strips. I don't know if this is due to lack of display precision, or whether these gaps are going to be show stoppers. I'm doing all of my conceptual modeling in discreet 3ds max, not because it's necessarily better, but because I know it very well. Anyway, I can see that the gaps are there when I import the file in via IGES, and I need to weld shut the vertices of the polygonal mesh. When I build my physical model, I'll be looking closely to see if I can easily close the gaps. I'll be outputting the .dwg file at 1/2" = 1 foot, or 2' long for my boat, so that should be big enough to be able to tell. Another thing is that I'll need to produce two Rhino models; one that is strictly for unrolling, and another that has the actual hull concavity up around the bow so that I can plot the bow crash bulkhead. I wish that I could get the file to work without these disquieting anomalies, so anyone please sing out if you have answers! ShipConstructor's ShipCAM sounds like it could do the trick, but 9 grand for software is a bit out of my league. From: Russ Ashworth Date: Fri Nov 16, 2001 2:30 am Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META At 09:01 AM 11/15/01 -0500, Gary H. Lucas wrote: Sorry about that! So what is leaning you towards steel? I work in aluminum every day, for machinery that needs to be light and corrosion resistant, in the commercial greenhouse industry. After owning several fiberglass boats I've always wanted an aluminum boat, despite such issues as electrolysis. There is an aluminum Swain boat in a yard at the top of the hill in Nanaimo. Gene Wunderlin took me to see it a couple of years ago but I can't remember the name of the guy who is building it. He makes self steering gear. Russ Ashworth From: jmatt@e... Date: Fri Nov 16, 2001 10:14 am Subject: Re: [origamiboats] converting offsets to origami templates On Thu, 15 Nov 2001 14:23:57 -0800, you wrote: >Well, here's the reader's Digest condensed version- it may take me a while >to get the full tutorial done. Thanks, thats more than I knew before. Some pondering time required here. JM From: "Alex & Kim Christie" Date: Fri Nov 16, 2001 3:39 am Subject: aluminum swain hull in Nanaimo I think the first name of the fellow who is building the Swain hull in Nanaimo is Arkon. Ring a bell for anyone for the last name? Alex Christie From: douglind@s... Date: Fri Nov 16, 2001 3:58 am Subject: Re: MBQ & Brent Swain -- plus META I have just discovered this site and it is quite interesting. I am leaning towards steel instead of of aluminum for a couple of reasons. I had reservations about rusting out from the inside on steel but here I have learned that with proper preperation of the hull this doesn't have to be a worry. The other concern I had was resale value. Here I also found out that the original cost is a lot less so that would explain the difference. I think a steel hull is also stronger than aluminum, and there is the electrolysis on aluminum. I know this can be controlled but it is not such a worry with a steel hull. From: "Darryl Carriere" Date: Fri Nov 16, 2001 5:52 am Subject: Re: [origamiboats] aluminum swain hull in Nanaimo his name is Erkan at 250 755 7810 Darryl From: arthur nogueira Date: Fri Nov 16, 2001 2:43 pm Subject: RE: [origamiboats] aluminum swain hull in Nanaimo Hello!, My name is Arthur Nogueira and I have been following your discussion for a while. I could not, however, visit the site where I hear everybody saying there are lots of photos. Could you please help me with how to get there? Thanks. Regards, Arthur From: arthur nogueira Date: Fri Nov 16, 2001 3:04 pm Subject: RE: [origamiboats] Re: MBQ & Brent Swain -- plus META Hi! I am interested in metal boats (I have a fiberglass one currently), but all I ever heard seemed clearly biased towards aluminum. Have you read Michael Kasten's comments at http://www.kastenmarine.com/ ? Three conclusions seemed obvious to me: a) for the same weight, aluminum is stronger; b) aluminum will not corrode from the inside; c) electrolysis is fully controllable. It remains that aluminum is more expensive. But then there is the fact that you do not have to paint aluminum above the water line. Kasten's conclusions are, and I quote: "In choosing between steel and aluminum, the deciding points are mainly in the realms of: I. Budget: Many builders can provide an alloy vessel for less money if it is not painted, except on the bottom. II. Maintenance: What is not painted will not need to be re-painted. III. Resale: An aluminum boat will have a much higher resale, allowing any minor difference in original cost to be more than recovered. IV. Weight: As we've seen, aluminum wins this one, and in a larger vessel, will permit lighter displacement, a smaller engine, and greater range. V. Carrying Capacity: Less weight being given to structure will allow more to be put into fuel or cargo. VI. Stability: Aluminum wins again due to being lighter and therefore permitting weights to be lower down. With correct design, adjusting the vessel to suit the material, there is no reason to prefer one material or the other, unless steel will be top-heavy for a given vessel size restriction. VII. Strength: The overall point to be kept in mind is that an aluminum structure can be made with much larger scantlings, the same or greater strength, and still be much lighter than a similar structure in steel. In simple terms, aluminum is structurally more "efficient" than steel." Would you mind further elaborating on your favoring steel? In particular in relation to the preparation of the hull to avoid inside corrosion? Maybe I am missing something here and I would rather make an informed decision before actually starting to cut through sheets of metal. Thanks. Arthur From: winslow59@y... Date: Fri Nov 16, 2001 6:51 pm Subject: Apologies for lack of clarity re: MBQ article. I extend my apologies to the board if I gave the impression the MBQ article by Brent Swain, or the META article, are available online. Metal Boat Quarterly, the magazine puplished by the Metal Boat Society, is mailed to MBS members and not available on newsstands or online (currently). I thought some mention of it here would provide an opportunity for those interested to seek out a copy of the magazine. You can go here: http://www.metalboatsociety.com/mbs/members.php to request a sample copy of the MBQ and get information about the MBS. Note: Other than being a MBS member (primarily to get the magazine), I have no affiliation with MBS. From: "Gary H. Lucas" Date: Sat Nov 17, 2001 3:59 am Subject: Re: [origamiboats] converting offsets to origami templates Doug, On the Rhino newsgroup I describe myself as a block and cylinder guy, not the sexy curves kind, so there is a lot I don't know about using Rhino. However I don't think what you are describing would be considered an Origami type of construction in the Brent Swain context. The construction I believe you described is more like the Van De Stadt type of construction. A while back Alex posted a file that you could print, cutout and tape together to see how a Swain hull goes together. I posted a revised version with lines showing how ALL the elements of the single sheet of metal which forms a Swain hull are actually CONICAL sections which you would form in Rhino using Rail Revolve not 2 Rail Sweep. You might look for that file to see what I am talking about. If you are interested I can send you my crude Rhino model that may help you understand how I came to this conclusion. I printed the model out on paper and cut out the two hull sides, the transom and a deck, then taped them together to prove that all the surfaces would assemble properly. In reality no metal stretching is required to pull the hull together properly, so a very accurate pattern can be made and assembled. Brent welds in the angle iron longitudinals that warps the metal slightly and the result is that the conical sections become somewhat spherical and actually makes the hull even fairer. The construction you describe depends on very accurate assembly and very careful welding to produce a fair hull. Brents method almost guarantees a fair hull. I use the term 'fair' here to describe a hull where all the curves blend smoothly into one another and there are no 'hollows' where the curves reverse. I am not sure of the terminology though so my description may be a little off. My model is not a very good looking boat, but it proves the point of Origami construction. Gary H. Lucas From: "Doug Barnard" Date: Sat Nov 17, 2001 9:21 pm Subject: RE: [origamiboats] converting offsets to origami templates > From: Gary H. Lucas [mailto:garyhl@m...] > However I don't think what you are describing would be considered > an Origami type of construction in the Brent Swain context. The > construction I believe you described is more like the Van De Stadt > type of construction. Ah! Excellent discourse here! I was wondering the same. It was for this type of feedback that I posted my methodology. I'm no great shakes at Rhino myself, or at computer-aided hull design. Having to sit there with my hat in my hands, as experts told me what was what, hasn't been a problem since I got out of my teens! > A while > back Alex posted a file that you could print, cutout and tape together to > see how a Swain hull goes together. I posted a revised version with lines > showing how ALL the elements of the single sheet of metal which forms a > Swain hull are actually CONICAL sections which you would form in Rhino using > Rail Revolve not 2 Rail Sweep. You might look for that file to see what I > am talking about. If you are interested I can send you my crude Rhino model Yes, please do! I'll send you my model as well. Please post any commentary that you have on it for any that would like to make additional comments. When it comes to putting my hard earned $$$ on the line to build a big damn boat, my ego takes a backseat! > In reality no metal stretching is required to pull the hull > together properly, so a very accurate pattern can be made and assembled. Can't wait to see it! > actually makes the hull even fairer. The construction you describe depends > on very accurate assembly and very careful welding to produce a fair hull. In Brent's book, he describes cutting out six square panels, and saying that the only way to put them together will form a cube (I paraphrase here). When you see the strips that are formed by the Unroll process, you can see that their curves aren't "parallel"; that they require bending to be able to put them together. When I build my 2 foot model, I'll be able to see this more clearly. I'll be sure to post pictures. I can see that having transverse patterns, from various stations, would be a handy thing when welding up the hull. Maybe even tack on the side decks before attaching the hulls together? > My model is not a > very good looking boat, but it proves the point of Origami construction. One of the reasons that I went with the strip approach is that the hull lines seemed to want it. The lines of the trawler are more broad through the design than the sleeker lines of Brent's boats. Maybe it's a lack of expertise on my part, or maybe its one of those ragbag vs. smokepot things. More work is definitely called for! I think that what were doing here is an important thing, in that with the refinement of these techniques, we can make it so that basically *any* chined boat can be built cheaply and efficiently by backyard builders. Whether it's origami, Van De Stadt, or some mix of the two remains to be seen. I just want to get myself going on the waterways! One of the big messages that I got from Brent's writings is that origami-type construction is the fastest way to get from Point A (boatless) to Point B (cruising the world in an optimum, paid-for yacht). Last weekend, I took a tour of a total-Bristol Nordhavn 46 that is going down to the south coast of Mexico in a few weeks. Absolutely phenomenal trawler, incredibly well set up. I just checked my accounts, and I seem to be a bit shy of the $500K to go out and get my own! Hmmm... maybe if I check under the couch for dropped change? Thanks for the response! From: "Alex Christie" Date: Sun Nov 18, 2001 2:11 am Subject: The need for a compact liveaboard trawler yacht Very interesting experimentation going on here with Rhino 3D being used to unwrap a chined boat. Might I direct some of our common thought toward the idea of a short, fat power vessel? While it is the antithesis of the sleek, ocean- crossing sailboats, it has some virtue for the mostly dock-bound liveaboards. While I am planning to build the 40 foot sailboat, it has struck me that for those who plan to travel only coastal routes a trawler-type yacht would suit fine. If you are to be a full-time liveaboard with 95% of time to be spent tied to the dock, then the need for an ocean crossing mast and sails is also downgraded, and the money can be either saved or plowed into on-board luxuries. A nice big good- looking steel power vessel could really fit the bill. 36 feet of power vessel on a wider beam than the sailboat would likely produce a liveaboard of very spacious accommodations, easily on par with the 40 foot sailboat, would it not? Phil Bolger once did a fun workup of a "Trawler Houseboat", only 30 feet or so long, very beamy, and quite lofty. While not intended for ocean-crossings, it was seaworthy (he made no promises for comfort, but did indicate that it wouldn't sink in big waves - ie the crew would be worn out long before the boat was). The origami system works very well with moderately-beamed hulls; I wonder what extra reinforcements other than longitudinals and bulkheads would be needed for stiffening the larger skin surface areas of a high-sided power vessel? It is such a different kind of hull that it is likely to need a lot of thought to do it right. Something to think about. Alex Christie From: "Alex Christie" Date: Sun Nov 18, 2001 2:13 am Subject: Re: aluminum swain hull in Nanaimo Dear group, I had a look in Nanaimo for the Erkan aluminum Swain hull, hoping to capture some images for our photo files, but did not find it on Prideaux where the train tracks cross it. Perhaps he has moved it, or launched it? Anyone have some info on this? Alex Christie From: "Daryl Carriere" Date: Sun Nov 18, 2001 3:35 am Subject: Re: [origamiboats] Re: aluminum swain hull in Nanaimo I just talked to Erkan on the phone , his boat is still in his yard at 145 Prideaux. The tracks cross Prideaux in two places. Darryl From: Alex and Kim Christie Date: Sun Nov 18, 2001 5:40 am Subject: re: location of aluminum swain hull in Nanaimo Ahah, it was in the back of my mind that this may have been the case, the tracks crossing the road twice, but I didn't act on it. Will attempt another try on my way back up Vancouver Island on Monday. Everyone keep their eyes peeled for new photos, should I have some success! Alex Christie From: kupris1948@a... Date: Sun Nov 18, 2001 12:58 pm Subject: inorganic zinc rich primer recoat time, is there any? I would like to leisurely sandblast an interior and prime as I go. I work alone and outside. I want to overcoat the zinc primer with coal tar epoxy . Will there be a time limit between zinc and zinc or zinc and coal tar? John. From: "Doug Barnard" Date: Sun Nov 18, 2001 6:12 pm Subject: RE: [origamiboats] The need for a compact liveaboard trawler yacht Great point, Alex. As cool as the Swain designs are, they are just one kind of boat. To me, one of the most appealing things about building a boat for myself is that I can build exactly what will be of the most use to *me*. Trying to fit into other molds ain't what it's about, man! I'll continue to share successes and failures with the list as I work through the design process. Hey, I don't want to share my anchorages exclusively with leased fiberglass eyesores! > Phil Bolger once did a fun workup of a "Trawler Houseboat", only 30 > feet or so long, very beamy, and quite lofty. Sounds suspiciously like the infamous "Busted Flush", owned by John D. MacDonald's fictitious Travis McGee! > The origami system works very well with moderately-beamed hulls; I > wonder what extra reinforcements other than longitudinal and > bulkheads would be needed for stiffening the larger skin surface > areas of a high-sided power vessel? This is of concern to me, as well. Brent tells us that when traditional designs are holed, it tends to happen at the transverse ribs. I have the feeling that I'll need to add some rib/bulkhead bracing, but how much? From: rct_51@h... Date: Tue Nov 20, 2001 5:55 pm Subject: Re: inorganic zinc rich primer recoat time, is there any? If you look in the ICI Devoe coatings website they have tehnical data sheets. Catha-cote 302 reinforced inorganic zinc primer seems to have a (self) recoat time of 90 days depending on conditions. International paints uses a different system that appears to be fairly fussy by comparison. Note that some manufacturers have replaced coal tar products recently because of the toxicity. They claim that some of the mastics will outperform coal-tar without the hazards. They may cost more too? There are disclaimers attatched to the data sheets that relate to intercoat delamination--contact your supplier is the last word. From: Doug Lind Date: Thu Nov 15, 2001 3:51 pm Subject: Re: [origamiboats] MBQ & Brent Swain -- plus META A lot of the reasons why steel was not my first choice are not there anymore. My major concern was that of floating around in a bucket of rust. I have learned that with proper preparation of the hull it will not rust out from the inside in 10 years. The second was resale value as this is still lower by far for a steel sailboat than one out of aluminum. Bringing into the fact that building a steel hull is a lot less, this concern has diminished. A steel will take more abuse and it does not have the same electrolysis as an aluminum hull. I haven't made my mind up completely yet, but these are the reasons why I am leaning towards steel. From: "Alex Christie" Date: Wed Nov 21, 2001 2:40 am Subject: New photos uploaded Dear Group, A day ago I dropped by to see Darryl Carriere's 36 foot steel Swain sailboat, and took a few photos for the group photo files. The snapshots are located in the album, "Darryl's Boat". The profile photo of his boat shows very well how fairness is acheived on these hulls without the use of fillers. Darryl has graciously loaned me many photos from his own collection showing both his and other boats in build, as well as a few of an Aluminum boat in Nanaimo. When I wade over to the school to use the scanner next week I'll scan them and post to the group. Alex Christie From: johnh94927@y... Date: Wed Nov 21, 2001 7:40 am Subject: Newcomer sez: Fantastic group And there's so much I want to know, of course... I guess I can start with the SHaler Junk. I searched under shaler and under junk, but didn't come up with much of what i was lookin fer. can anyone gimme info on on this cool-lookin boat? AND - anyone have any experience with any of Weston Farmer's steel desings? THe 32' Tahitiana wasn't origami, but he designed a smaller 23' sloop - I've forgotten the design name - that looked pretty cool. And... And... And... From: Stephen Wandling Date: Wed Nov 21, 2001 9:17 pm Subject: Re: [origamiboats] Newcomer sez: Fantastic group John, I am not clear on where you got the "SHaler Junk", but there is an Evan Shaler on this group and at evan shaler . Evan has built many of Brent's design for people at his site in Nanaimo, BC Canada. I don't recall if he has been involved in any junk rigged boats. Stephen From: "Alex & Kim Christie" Date: Wed Nov 21, 2001 10:50 pm Subject: Evan Shaler Junk John, The photos that you refer to in the photo album called "Shaler Junk" are indeed of a vessel designed and built by Evan Shaler. I am not sure, but I think Evan Shaler modified the building technique used for the Brent boats to build a steel version of Allen Farrell's famed CHINA CLOUD, a 42 foot wooden sailboat with junk rig in the tradition of the chinese junk. CHINA CLOUD is a rather famous boat on this coast, the stuff of legend, as well as the builder, who lives a nomadic life aboard, a paragon of simple-living. Evan can answer more about this himself, or perhaps Brent, but I don't believe he did up actual plans. With his long experience building Brent's boats he just "did it"! Alex Christie From: Stephen Wandling Date: Thu Nov 22, 2001 12:11 am Subject: Re: [origamiboats] Evan Shaler Junk Alex, I don't see "Shaler Junk" in the Photo Album, but I see the "Bellavial" listed under "42' Steel Brent Swain junk schooner" in the Files section. Is this Evan's boat? Stephen From: "Alex Christie" Date: Thu Nov 22, 2001 1:23 am Subject: Re: Evan Shaler Junk Stephen, The photo album of 4 photos of the Shaler Junk are in the new "Photos" section now offered on Yahoogroups (the photo of Bella Via is in the old "Files" section, formerly the only place photos could go). After you click on "Photos" you'll see it three rows down and two albums over from the left. regards, Alex Christie From: Stephen Wandling Date: Thu Nov 22, 2001 2:14 am Subject: Re: [origamiboats] Re: Evan Shaler Junk Alex, Ah, the mind works in strange and interesting ways. For some time now, for reasons I don't think I even want the answers for, I have been going to the junkrig site at yahoo and looking for origami stuff. I recall your fairly recent message about rearranging photos and recall that when I looked I couldn't find them. Thanks for your patient guidance. I have never seen these photos before. What a beautiful boat and seeming homage to Allan Farrell's "China Cloud". Is this boat engineless as it appears? If so I am doubly impressed. Thanks. Stephen From: origamiboats@t... Date: Thu Nov 22, 2001 3:38 am Subject: Shaler Junk engine Yes, Evan has done a great job on his junk. I believe the Shaler junk is powered by diesel engine. Like Farrell's CHINA CLOUD, it has twin keels, though I don't know if they are more like Brent's boats or not. Evan's rudder appears to be fixed on a skeg, as per the Brent boats, as opposed to Farrell's traditional junk rudder which goes up and down with a block and tackle. Some time Evan will sign in on this and set me straight on the subject! Alex From: evanmoonjunk@y... Date: Fri Nov 23, 2001 3:12 am Subject: Re: Shaler Junk engine Hi Alex, I fanally checked in again to see what is going on, I guess I should look at the pictures more often to see what's there! Here are some answers to the questions flying around. The basic construction is based on Brent's method with variations. All the components are pulled together the same way except the bottom of the hull. When I came up with the idea of building this boat(a long time ago) I spent a great deal of time talking to Allen about China Cloud, pros and cons etc. He insisted that a flat bottom was important so I incorporated that into the design. So instead of a V as in Brent's boats there is a section in the bottom that is flat(with a curve fore and aft) that is shaped like the bottom of a dory. This made for interesting challenges pulling 3 plates together for the hull but it worked. If I was to do it again I would do it with a shallow V for ease of construction and to get a bilge area which I don't have much of now. At the time that I conceived the idea to build this boat I had already built quite a few of Brent's boats and wanted the challenge of building something a little different. I developed the concept the same that Brent did, with cardboard models. Allen had a wooden half model of China Cloud plus his lines and ofsets(which are also in the book about China Cloud, "Sailing back in time"). I started off with half inch to the foot models geting the shape as close as I could to the half model(about 7 of these) and then went to 1 inch to the foot (3 of these). From the final model I was abel to take accurate measuerments to make scale drawings from which I could loft out the hull, decks etc. The boat draws about 4' 10". It is a lot heavier than China Cloud because of steel, Engine, fuel tanks, twice as much water etc. I also wanted to go deeper draft(extra 18") for better windward performance which it did accomplish. The keels are bigger than I should have gone. The length of them was based on China Cloud forgetting at the time that a wood boat needs a lot more strutural support than a steel boat. Oh well live and learn! There is 200 gallons of water in the keels plus 2000 lbs of lead plus a sump in each end. Yes there is an engine as in my last boat (a Brent 31') I could not afford one ,this time I wanted one. I originally was going to go hydraulic drive, but as I could not afford that either I settled for an ancient 2 cylinder Hercules(circa 1945) The rudder is fixed on a skeg using all the same methods as on Brents boats. If you have any more questions feel free to ask and I will be happy to answer them.....Evan From: robertgm77@e... Date: Sun Nov 25, 2001 1:05 am Subject: Peugeot motors/ beamier boats I am really enjoying all the discussion.All info is good from my standpoint.I am at the stage of either building a boat or buying someone elses dream.I have the opportunity to buy a 36 ft steel Spray finished hull with a new 52hp Peugeot motor,maybe known as a Vetus motor.Does anyone have experience with these motors ? How about Sprays,pros,cons? I have done the usual research,Bruce Roberts website,books but do not know anyone who has sailed one.Re building a boat, has anyone built a beamy,ie 12 to 14 ft,cruiser 36 to 40 ft length via origami method ? From: carlmbentley@y... Date: Sun Nov 25, 2001 7:44 pm Subject: brent's book hello all, great message board. i have several questions, but before i start asking - i'd like to buy the book to make sure i'm not missing anything. some quick questions first though, how much is that in u.s. $? is this still the correct address (see below)? is the book available year round ? thanks in advance carl From: "Alex & Kim Christie" Date: Sun Nov 25, 2001 8:17 pm Subject: Re: [origamiboats] Peugeot motors/ beamier boats Re: Robert's question about the Spray: Pros: Lot of purists poo-poo the Spray, but it is a great boat for living on --- being heavy and wide not much will throw it about. Lots of people have made successful voyages in them, and are happy with their boats. Sailing upwind may not be their forte, but that hasn't stopped people from using them, same as with junk rig advocates. With all that beam, you are getting your money's worth when living in a marina compared to most any boat out there, and probably could live very comfortably a 35 foot Spray with aft cabin. Lots of people on this coast, with its light summer winds, are very happy with their big Sprays, and don't mind firing up their big 120 hp Lehman diesels to get somewhere (the Spray is not a light air vessel, nor is it a light engine vessel). I've read that they come into their own after 25 knots of wind. Anecdotes have also come in about how the sails blow out quite often because the boat is so stiff and won't yield to an oncoming blow. Make sure you have a good set of storm sails, or religiously reduce sail on any rising wind. Cons: It is likely better to buy a Spray from someone else has used ten years of their life building. This is the heartbreaking truth about building heavy displacement boats with tons of extra bits to fit and weld. If you can get this finished Spray hull with engine, and all for a good price, and plan on living aboard full time, then go for it, why not! When building, boats cost by weight, not by length. The steel Spray hull is one of the heaviest you can find, therefore it is easy to use up your building budget just getting out the basic hull, never mind finishing it off. Compared to the quick building of a Swain hull, the Roberts Spray will take you years to build with its mile and miles of internal framing. The Swain hull is probably the lightest steel boat possible for a given length, is faster to build with less welding runs on the hull skin (hence less distortion), and requires no filling and fairing. In Canada you can buy your steel pre-primed, avoiding the need to sandblast before painting. Two 40' boats have been built using the origami methods, and one 39' is in build in Alberta. I am planning on getting across the Big Water to Vancouver to see and photograph two of these boats this month, so keep an eye out for an anouncement on the board about them. Also, I'll be seeing the 39 footer over Christmas holidays. Regards, Alex Christie From: Stephen Wandling Date: Sun Nov 25, 2001 8:20 pm Subject: Re: [origamiboats] brent's book I believe the address you have is an older address. Brent's own recent directions to me were: > For a copy of my book please send $20 plus$3 for postage (prefer money order ) to 3798 Laurel Drive, Royston, BC V0R 2V0 . > Thanks. Brent Swain This is his parent's house and is where I bought my copy. Send him US$20 and you will probably get free postage. The book is available all year round and is well worth the price. It's thin, but full of new ideas, hence the subtitle "A Heretics Guide". Stephen From: "Alex & Kim Christie" Date: Sun Nov 25, 2001 8:34 pm Subject: Re: [origamiboats] brent's book The price for Brent's book to a US address is $20 US, plus $3.00 shipping. Brent may confirm this shortly, as well as the address question (I have Campbell River as his mailing address). Regards, Alex Christie From: Stephen Wandling Date: Mon Nov 26, 2001 7:30 pm Subject: Steel boat construction in Vancouver BC?? I am in the process of completing someone else's 'dream' in the form of a 35' steel boat. The project had stalled because of the usual lack of funds, but this has changed and I am now eager to proceed. I had lined up a great guy with a portable welding rig who knew boatbuilding, but now he is off to Alberta because of a lack of work here. Given the time of year and the fact that sandblasting/coating will take place right after the steel work is completed, I am looking to do the work inside, which means moving the boat from the outside storage its in, to either a yard or some other inside space. Does anyone out there have recommendations for either a welder/boatbuilder or a small yard that might be suitable for this project? I'm not looking for the 'cheapest' or the 'best', but rather, a good, solid person/yard to finish things off. Any suggestions will be appreciated. Stephen From: Russ Ashworth Date: Tue Nov 27, 2001 12:17 am Subject: Re: [origamiboats] Steel boat construction in Vancouver BC?? Steve, Try Reed Point Marina. They have some covered spaces. Russ From: Russ Ashworth Date: Tue Nov 27, 2001 1:17 am Subject: Dickinson Stove Hi all, As some of you know I had planned to build myself a boat and in preparation I bought an old Dickinson diesel stove to rebuild and play with so that it would be ready to fit as soon as I got the deck on (or sooner). :) It has been completely gutted and rebuilt with new burner, baffles, fire bricks etc and it works fine. Meanwhile my wife said that there is no way that I am ever going to build a big boat like that and in any case we don't have the space to build it so go and get a little one and go sailing. Which is what I did. Hey, if your wife told you to go and buy a boat, what would you do?:) Well,I am now the proud owner of an 18' 6"F/G twin keel Alacrity sailboat... and a Dickinson stove. Try as I might I can't figure out how to fit the stove in the boat. So, if anybody would like to make me an offer for the stove or would like to trade for a small flued kerosene stove (and I do mean small) just give me a call. I am in Vancouver. Russ Ashworth From: "Douglas Pollard" Date: Tue Nov 27, 2001 1:26 am Subject: Re: [origamiboats] Dickinson Stove Russ, Be careful of those diesel heaters they put carbon in the air. You will find yourself cleaning a certain amount of soot. I am nearly 70 years old and have known many people who have lived aboard for long periods of time. I know several who have lung problems from such stoves. At least that's what they are claiming. I suspect mildew could be a cause also. Anyway its worth being careful. Lots of ventilation!! Doug Pollard From: "Alex & Kim Christie" Date: Tue Nov 27, 2001 3:33 am Subject: Safety of stoves, Dickenson et al A lot of people blame the machines they live with for damaging their health, while paying little attention to basic maintenance of said machines -- an age old problem that is most prevalent in our treatment of automobiles, but extends to all areas of our lives. My general impression is that Dickenson stoves are quite well made and don't create soot if the fuel is properly combusting in the burning chamber (the pot). Also, in a properly functioning stove there is no output of soot into the boat interior -- that's what the flue pipe is for! The main way to get such a problem would be from having A) a faulty, gummed up carbeurator and B) a blocked flue pipe or flue pipe with too many bends and turns, constricting the draft. What usually happens is that people use the stove for years and years without maintaining it, expecting all the while that it should function perfectly, then they blame the stove when it ceases to function properly. Even heating systems in houses need periodic maintenance, yet people persist in ignoring their maintenance, to their peril when they feel dizzy from carbon monoxide poisoning. Living aboard requires that one maintain the systems upon which you depend so that such problems as under-carbeuration don't occur. That is, "a machine is only as good as the human maintaining (or not maintaining) it!". Alex Christie From: "Douglas Pollard" Date: Tue Nov 27, 2001 3:53 am Subject: Re: [origamiboats] Safety of stoves, Dickenson et al Alex, You are exactly right and that's why I said be careful. I also have one and have used it a long time. A pot burner has never been considered clean burning and even generating plants who of course don't use this type of furnace, but use gun type burners which are probably the ultimate in efficiency use scrubbers to clean their stacks. All it takes is a gust of wind across a ventilator or slightly open hatch you have a slight vacuum in the boat and a downdraft. What I'm talking about is long tem accumulated effects. I have never seen a boat with such a stove that could stand a white glove test. I am not saying don't use one I'm saying, "Be careful." Doug From: Russ Ashworth Date: Tue Nov 27, 2001 5:13 am Subject: Re: [origamiboats] brent's book At 12:20 PM 11/25/01 -0800, Stephen wrote: The book is available all year round and is well worth the price. It's thin, but full of new ideas, hence the subtitle "A Heretics Guide". Stephen Brent's book is well worth the money for the philosophy alone even if you are not building an origami steel boat. It will give you a new view on what is important, what to spend your money on, and how the modern boat manufacturing industry is conning the average boater out of 1000s of dollars. So if you've got barrels of money to burn then don't read the book, otherwise..:) Russ Ashworth From: "Alex & Kim Christie" Date: Tue Nov 27, 2001 5:54 am Subject: Re: [origamiboats] Safety of stoves, Dickenson et al I agree with Doug, the pots used in diesel stoves are a might primitive and not terribly efficient, and sure is an area that could use some research and development. Some are more prone to carboning up than others (sometimes within the same model line, go figure), and that, coupled with a tendency for users to run them on the lowest setting (they otherwise make the cabin roast) plus the downdraft problem he mentioned probably accounts for the soot. So do take Doug's advice, be careful how you use them. (I use propane!) Something else I have often wondered about in terms of cumulative effects is the breathing of diesel vapours/fumes from the engine compartment. In most boats, the engine is not truly compartmentalized from the rest of the cabin, and over the years as fuel line leak, the oil pan drips, and even exhaust leaks from around the head (at least on this 10 hp Volvo diesel we had). All this just goes right into the living quarters. Doesn't it make sense to seal off the engine from the rest of the crew? Anyone have some experience with this? Our last liveaboard boat had a completely separate engine compartment, and it made life very bearable, plus we didn't have that tell-tale diesel odour clinging to our clothes when we visted the land-dwelling cousins. Alex Christie From: Russ Ashworth Date: Tue Nov 27, 2001 2:16 pm Subject: Re: [origamiboats] Safety of stoves, Dickenson et al Running a seperate inlet from the deck to near the stove, having enough flue hight and a reasonably straight run all help too as they would with a solid fuel stove. A friend of mine had a Dickenson that often smoked but his flue was only 4 ft high and exited on the side dech below cabin top level. Plus he had a but solid dodger. You might also like to check out this site about balenced flues. http://www.nbasic.demon.co.uk/sailing/balflues.htm Other reasons for keeping the engine in a separate compartment are fire safety and to keep the bilges dry in the event that the cutlass bearing (constant drips) or a through hull leaks. Russ From: "Douglas Pollard" Date: Tue Nov 27, 2001 10:40 pm Subject: Re: [origamiboats] Safety of stoves, Dickenson et al Alex, I have also wondered about diesel fumes. It does seem to me that there are respiratory problems among a lot of long term live aboards. Since we are on this subject I'd like to say that gassing batteries in the boat that are not vented overboard may be a health risk. Mine are under the settee I have six of them. I presently use Gel cell batteries all though I think they gas some too. Besides that I originally used Prevailers but since they have been bought out by an American company I have not been able to get more than about 30 months out of any I have bought. I have been told by a battery salesman that the company that bought them out did not by the process under which they were manufactured. Who knows? So a separate engine compartment with batteries in it, except for the heat problem might be a good idea. Another thing I think is a problem is the wooden interiors put in most boats. Mold grows between the inner and outer hulls. You can't see it and you can't get rid of it easily. I insulated the hull on my boat thinking there would be no sweating and therefore no mold. That didn't work. I would make all interior wooden sections in the hull and overhead removable so they could be cleaned every couple of years. I watched a man with tears in his eyes put a forsale sign on his boat because the doctor told him that he was going to die if he didn't get off of it Also keep those Radar units up high and take care with the poison bottom paints. Anyway that's all I know ,or think I know about this dreary subject. LIVE LONG AND SAIL FAR.. Doug Pollard From: "Douglas Pollard" Date: Wed Nov 28, 2001 12:31 am Subject: Re: [origamiboats] Safety of stoves, Dickenson et al Rus, That's a good site. He may have worked out a good solution. A little vacuum in the boat wouldn't seem to make any difference to the stove at all. Doug From: rct_51@h... Date: Wed Nov 28, 2001 1:06 am Subject: Re: Safety of stoves, Dickenson et al Alex: how did you engineer the separate engine compartment? I am interested in researching this. Diesel has much to recommend it as a safer power source--living with it when you are not running it seems to be the challenge. As I mentioned before, i have developed a significant intollerance to the stuff. Still putting the keel on between rain storms so it's not a crucial issue yet. Thanks, rt From: carlmbentley@y... Date: Wed Nov 28, 2001 8:45 pm Subject: Re: brent's book no word from brent yet ? can anyone provide the most recent working address for ordering the book, i'll take my chances. -carl From: Stephen Wandling Date: Wed Nov 28, 2001 8:53 pm Subject: Re: [origamiboats] Re: brent's book As below, my directions from Brent were to mail $20 plus $3 postage (US funds apparently accepted at par) to: 3798 Laurel Drive, Royston, BC V0R 2V0 This is his parent's house and they apparently are handling this for Brent. It is where I went to buy my copy when I visited the Island. Stephen From: "Alex & Kim Christie" Date: Wed Nov 28, 2001 10:01 pm Subject: Re: [origamiboats] Re: brent's book The Royston address should work fine, it is his father's place, and I think he checks in there regularly. Alex From: david@t... Date: Thu Nov 29, 2001 7:09 am Subject: Sailing Ability Hi all There have be lots of posts about building Brents designs but I have not seen anything on what they are like to sail, how comfortable they are and how they perform in a storm. I have followed the discussions with interest, it has wetted my desire to find out more. I aim to cruise around the world in my retirement and are currently looking at designs and constructions methods. Bretts method is about the simplest I have seen but that is only part of the equation. What are they like to live on and what are they like for cruising. Looking forward to your replies. David From: "Michael Casling" Date: Thu Nov 29, 2001 9:10 pm Subject: Re: [origamiboats] Sailing Ability David, are you in New Zealand if so may I ask where? If you are in NZ I would like to here your thoughts on the designs and construction types currently available. Also what would you be comparing the Swain boat to that is available locally. I was in NZ 1948 to 1968 and have made several trips back. My brother owns a Lotus 10.6 in Tutukaka. I am most familiar with the Bo Birdsall designs and was going to get one built in Auckland in the early 80's but I got married in 1984, bought property and kept my Tanzer 8.5 which is of solid fiberglass construction. The Swain designs are of interest to me based on initial cost plus the total time involved to build. I am a fin keel fan but must admit that the twin keels and rudder skeg make it easy to beach and clean the bottom. What attracted me to the Birdsall design was the overall performance, to be able to break out of the displacement mode off the wind, but probably at the expense of comfort on the wind. At 17000 lbs for a 36 foot boat the Swain would be solid into the seas. As a cruiser the depth of the hull would be a benefit and in my opinion I do not think the hard chine would make much difference. The people who have sailed on the 36 can provide more input on this. The other consideration is the living comfort inside in different weather conditions. Vancouver BC is similar to Wellington in terms of temperature and rain but not as windy. It does seem as though a wooden boat or even fiberglass would be more cosy in lousy weather. Again the Vancouver sailors can answer that question. You have also asked the question about sailing performance ( I have my theories based on my own experience and think it would sail similar to my current boat but with the advantages of being larger and having a longer LWL ) but I also look forward to the replies from Brent and or others. Michael Casling From: Richard Payne Date: Fri Nov 30, 2001 9:58 am Subject: Re: [origamiboats] Re: brent's book I would like to order Brent's book also, if I could find out how to, and what charge there would be for airmail to Australia. Regards, Richard Payne. From: "Jesús" "Alborés" Date: Fri Nov 30, 2001 4:03 pm Subject: Re: [origamiboats] Re: brent's book Richard, I write you from Spain. I asked for Brent's book, enclosing US$30 (20 for the book, 10 for the airmail postage), at the following adress: 3798 Laurel Dr, Royston BC V0R2V0 Canada That was about a week ago; today Brent email me saying the book was sent a couple of dayys ago. So, this is the right adress, and the answer comes very promptly. I wish Amazon would be near so quick as Brent. Regards, Jesus From: Mark_Schlichting@h... Date: Fri Nov 30, 2001 8:33 pm Subject: Re: Sailing Ability/Living Aboard My wife, Jean, and I built our 36' Brent, Costa Vida, primarily to live aboard and have been doing so for a year and a half while completing the interior. It's great! We moved from my old 35' Colvin - a steel Saugeen Witch - and the Brent boat has at least 30% more interior space due to higher freeboard and 6" greater width (maybe the frameless construction method contributes too). Because the fuel and water tankage are in the keel and not under the settees we also have a lot more storage (ours is a fin keel). With our woodstove heat the boat is really dry (even here on Vancouver Island) and with a decent propane stove/oven and shower (with demand propane Bosch water heater), its a pleasure to live on. We specifically used light wood for the cabinsides (maple) and white painted bulkheads, plus an extra port in the main cabin to give a open and spacious feeling interior. The 6'2" headroom certainly helps as well, especially compared to the 5'9" on the Colvin. We haven't done any offshore sailing yet but the local cruising we've done so far has shown the boat to perform very well. We went with a 47' mast stepped on deck and sprung for a new mainsail with a used Genoa and Staysail and she moves nicely. We have heard many first hand accounts of how well the design performs in offshore conditions. Shinola's windward beat back to NZ by way of Hawaii was apparently quite dry compared to the other boats cruising in company. The submarine type companionway hatch creates a watertight seal quickly and easily - a lot better than slats and a turtle hatch. I believe passage times on the Brents is quite respectable but you'll have to wait for someone with offshore experience to comment on that first-hand. From: david@t... Date: Fri Nov 30, 2001 11:14 pm Subject: Re: Sailing Ability/Living Aboard Mark Many thanks for the comments. The boats and their method of construction are great. I am sending away for Brents book so I can find out more about them. I looks forward to hearing more about their sailing ability. Regards David From: david@t... Date: Fri Nov 30, 2001 11:26 pm Subject: Re: Sailing Ability Mike Thanks for the reply. Yes I live in Auckland New Zealand. I have sailed on a Lotus 10.6 and found them to be a lovely boat. I currently sail a 25 foot lift keel trailer yacht. I am looking at cruising yachts for a planned cruise around the world. I have several options, buy an existing boat and refit her or build a new boat. I am not sure what option I will settle on yet, it depends on finances and wether anything suitable is around at the time. I like the strength of steel but was not sure about the construction. Broberts kitset boats were appealing due to their method of construction. I have also been looking at Michael Kasten designs due to their traditional looks. His ideas on gaf rig is also appealing due to the simple rig and low stresses. David From: rct_51@h... Date: Sat Dec 1, 2001 2:02 am Subject: Re: virus warning My program picked up a so called "as yet incurable" virus in Doug's last message. I deleted it instantly. Hope no one else got infected. Poor weather for building. I'm turning out pulleys for blocks out of UHMW plastic using a neat device I borrowed to bolt onto the bed plate of my drill press. Then i got some free time on a milling machine--makes an awsome finish. So far the cost of the pulleys has amounted to some minor scrounging expeditions. Picked up a Dickenson propane stove for a decent price. Got to build a pump for the head next. rt From: paull01@y... Date: Sat Dec 1, 2001 6:17 pm Subject: Re: Sailing Ability/Living Aboard Hi Mark and Jean. Those are real inspiring words for those of us who are planning and saving up for the kind of lifestyle you are already living. I realize how important it is to be able to have a shower inside in a climate where one is unable to have a sunshower out on deck or in the cockpit. Do you think you could send a sketch of your layout to the Files section? I am interested in seeing how you incorporate a shower stall into the design. Perhaps you could send some pictures as well? If you don't have a scanner or computer access to upload the files, just drop me an email and I could upload them for you if you send the sketches or photos to me in the mail. I'd send them back to you after I uploaded them. Also, does anyone know if Brent has incorporated a shower into his 31 footer? Paul Woodinville, WA From: paull01@y... Date: Sat Dec 1, 2001 6:41 pm Subject: Re: Shaler Junk engine Hi Evan. Thanks for all the info on your design and a description of the Origami process used by Brent. I was kind of hoping you were using design techniques that were inline with the philosophy and methods used in the construction process. I've been toying with the idea of an origami approach to Bolger's 35' Volunteer. It already has a (flat) steel bottom. I'm sure there would be a way (for mere mortals) to come up with a folding version of this type of design. I think the approach of making a model of the original - and working from that - makes the most sense. Bolger achieves a 2' draft with the use of leeboards. I'd also be interested in seeing the lines of your junk. Do you think you could post a 3-view to the Files section? If you don't have access to a scanner and computer, I could upload them for you if you sent me the sketches. I'm also interested in the length and beam and any other details about the rigging etc. you'd care to include. I know there was a nice coffee table book put out on China Moon. Do you know what the title is and if it's still published? Paul Woodinville, WA From: paull01@y... Date: Sat Dec 1, 2001 6:49 pm Subject: Oops Evan, I see the title for the book "Sailing Back in Time" was right in your post. (And my reply). I think I'd better get some breakfast. Paul From: Stephen Wandling Date: Sat Dec 1, 2001 8:37 pm Subject: Re: [origamiboats] Oops There is also the Dan Rubin book "Salt on the Wind: The Sailing Life of Allen & Sharie Farrell" if you want a more in-depth account of the Farrell's incredible lives on the BC coast. Chapters has it but Amazon doesn't. Figures. From: "Doug Barnard" Date: Sun Dec 2, 2001 8:34 pm Subject: adapting designs (was Shaler Junk engine) > -----Original Message----- > From: paull01@y... [mailto:paull01@y...] > I'm sure there would be a way (for mere mortals) > to come up with a folding version of this type of design. Thanks to the great efforts of List member Gary Lewis, I've tried some of his methods using Rhino 3D, and had less than rousing success. I'm paraphrasing here, but so far the two of us have found that the "split orange peel" look of Brent's plate development is pretty much specific to sleek sailing hulls. Junks and trawlers, with their more rounded bows, require more splits, or going to more of a strip approach. Gary turned me on to Van De Stadt, who also has a "speed building" approach. Frankly, it amazed me that in the whole wide world, only two guys have said, "Hey, this boatbuilding thing sure takes a long time!" Anyway, I've sent away for more materials, and the brand new book written be Van De Stadt about his designs. I'll report back to the list when the goodies arrive; as they'll be coming in from Holland, it might take awhile. I had good success with assembling a paper model of my trawler design. I've also refined the interior/exterior, and completed virtual flythrus of the exterior, interior and below decks. Next, I'll try for a larger scale model that incorporates a "bustle" (integrated swim step) and all of the cabin. Basically, everything that I'd have CNC cut. There was a disturbing note in the Rhino help file about a lack of precision *sometimes* when unrolling surfaces. Whoever wrote it said that *sometimes* it would produce unfair plates. No mention was made as to how to avoid this calamity, whether the plates had to re-cut, and just how bad the funkiness was. I'm also assuming that this poor fellow was trying to assemble the bogus plates on to a standard frame. The great thing about the folded steel approach is that it tends to be self-correcting, by pulling the gap together instead of leaving a gap that you could throw a cat through. So I'm not too freaked out by these events. From: brentswain38@h... Date: Tue Dec 4, 2001 7:47 pm Subject: Re: Safety of stoves, Dickenson et al On fishboats they have a saying "air in-air out" They install a fan blowing air into the engine compartment and another blowing air out. I think that a big one hooked up to the ignition switch, taking air out would be adequate, but the resulting vacuum in the cabin can cause serious downdraft problems for your stove if you don't let enough back in. Another solution , used on the Fab-all stoves ,is to have a separate , outside air intake for the stove. That way the stove burns only outside air and is sealed from the cabin. Any downdrafts on the boat put the same pressure on both the chimney and the air intake simultaneously. The first manufacturer of oil stoves which uses titanium for burner pots is going to be popular. When the Russian military collapsed , titanium production was cheap, so they re-directed it to civilian use . I've heard that you can go into a hardware store in Russia and buy a titanium shovel or garden rake for cheap.I've also heard that the Russian pilots are the people to talk to for Russian contacts if you want to import anything from there .A company could order titanium pots from Russia for less than they are now paying in the west for stainless. A titanium pot would last forever. Any oilstove manufacturers listening? Brent Swain From: Robert.Biegler@s... Date: Tue Dec 4, 2001 7:57 pm Subject: Re: material --- In origamiboats@y..., brentswain38@h... wrote: > The first manufacturer of oil stoves which uses titanium for > burner pots is going to be popular. There was a short note on a science website about half a year ago that a process had been developed by which one can get titanium from the oxide through electrolysis, same as with aluminium (don't ask me how they get titanium at the moment; apparently it takes even more energy). So I hope that in 5 to 10 years, titanium should come down to a price not far above that of aluminium. If that ever does happen, it'll be the day of titanium hulls, assuming welding is not any more difficult than with aluminium. Regards Robert From: brentswain38@h... Date: Tue Dec 4, 2001 8:13 pm Subject: Re: Sailing Ability One of my 36 footers sailed accross the atlantic from the canaries to the west indies , 2200 miles in 14 days . Another sailing west from Mexico to Hawaii covered 1006 miles in 6 1/2 days , beating into a 25 knot northwesterly. Another sailed from Sooke BC to San Francisco in 5 1/2 days. One owner built a 36 footer and sailed it around the Pacific, then built one of my 26 footers and sailed it through the Northwest passage, then built another one of my 36 footers to cruise the Pacific in again. His daughter is building one of my 26 footers. He wouldn't want any other design. Several owners have built several of my designs for themselves, and put a lot of sea miles on them. Most wouldn't even consider anything else . They sail well and with the more traditional hull shape are very comfortable at sea. Everyone I know who has built one of my designs and followed the plans has been very happy with them. Those who don't follow the plans are not my responsibility. All who I have worked for are still the best of friends. Brent Swain From: brentswain38@h... Date: Tue Dec 4, 2001 8:20 pm Subject: Re: Sailing Ability A well insulated steel boat would be much more comfortable in cold weather. There is no comparison between the insulating abilities of wood and sprayfoam insulation, sprayfoam is a much better insulator, and a steel boat is much drier;more watertight. Deck leaks on a well built steel boats are unheard of . They are the rule rather than the exception on older wooden boats . There is also a great deal of comfort in the form of peace of mind in a steel hull. Brent Swain From: Jim Phillips Date: Tue Dec 4, 2001 11:15 pm Subject: origami cats, design book Brent, I was wondering how I could purchase your design book. Do you design multihulls? After owning monos and sailing about 30 000 miles from Oz to the Med and around the Caribbean, we are now back in Australia and looking to build an aluminium cat via a frameless method over the next few years. Any info about your method and your design book would be greatly appreciated. Cheers, Jim. From: rct_51@h... Date: Wed Dec 5, 2001 1:45 am Subject: Re: material At present, welding titanium is still regarded as a fairly specialised process--it would be an expensive proposition for the average home builder. rt From: "Doug Barnard" Date: Wed Dec 5, 2001 2:59 am Subject: RE: [origamiboats] Re: material I believe that you have to heliarc titanium, a real pain! That stuff is gnarly! From: "batsondbelfrey" Date: Wed Dec 5, 2001 3:58 pm Subject: Re: material --- In origamiboats@y..., "Doug Barnard" wrote: > I believe that you have to heliarc titanium, a real pain! That > stuff is gnarly! Another nice idea shot down by reality. Sigh. At the moment I know next to nothing about welding, I am reading this group because the method seems interesting and I really *like* the idea of an impact resistant hull. I got an email reply from John Barker, but there was no text. John, your computer may have a case of Badtrans. Regards Robert From: "mat_man22" Date: Wed Dec 5, 2001 10:35 pm Subject: Re: origami cats, design book Jim, I am also on the lookout for an aluminum origami catamaran plans and have not found much. I would think the French designers might be a place to look (they are into cats and aluminum). This link is for free (?) 40' origami cat plans. http://www.mala.bc.ca/~bigras/ Please pass on anything you find. Thanks Mat From: Jim Phillips Date: Thu Dec 6, 2001 3:59 am Subject: origami cats, Brent's book & Tony Bigras G'day Mat, I had already checked out Tony Bigras' site. I think he is definitely on the right track with his unstayed biplane rig and alum hull - my plans exactly - but, unlike his design thoughts, I don't want to have any structure on the bridge deck. (We're inclined to a (nearly) horizontal alum bimini with solar panels on top that will provide very little wind resistance compared with a central pod but plenty of shade in the tropics.) Although he says he would be interested in talking about all this, I haven't made contact with him yet. His plans are not readily available. As we will not be in a position to build for another year or two, I am using this time to investigate the various methods and designs available. An aluminium Wharram is also a possibility. I have a sneaking suspicion, however, that I may have to design the boat myself using some of the freeware available on the net such as Hulls. In the meantime, do you know how I can get hold of Brent's book? Cheers, Jim. From: Richard Payne Date: Thu Dec 6, 2001 8:32 am Subject: Re: [origamiboats] Re: brent's book Thanks Jesus, I will order the book and am most interested to see Brent's approach to things. Regards, Richard. From: "dr01allen" Date: Thu Dec 6, 2001 2:37 pm Subject: Re: material actually TIG with argon can be used without much trouble. C, N, and O will intercalate at temps over 400, if present, so the surfaces need to be clean. check out the various titanium supplier websites for other machining techniques. da From: "alex_christie" Date: Thu Dec 6, 2001 6:20 pm Subject: attachments function suspended Dear Group, I have altered the setting to discard attachments in e-mails so as to avoid any more virus attacks. I'll review this change in a while to see if I should keep it like that in the future. It is certainly one way of keeping the viruses at bay. I have not sent any messages with attachments on purpose, but my computer did after being invaded by the worm. I have gone through the group messages and have deleted any with attachments and/or viruses. We can still share and view photos and text, however, by posting images to the Photos or the Files section. Yahoo scans files as you upload them, I believe, which is why it takes quite some time to upload. Hope this restores some confidence and encourages people to post! I've tweaked my computer to a very high level of security to prevent any attack (I guess a little paranoia is a healthy thing in some cases). Alex Christie From: "mat_man22" Date: Thu Dec 6, 2001 9:32 pm Subject: Re: origami cats, Brent's book & Tony Bigras Jim For Brent's book look at: http://groups.yahoo.com/group/origamiboats/message/444 Would be nice if Hulls would do it, but I don't think it will. Output to a plasma cutter would also be nice. Pro-E would work but is expensive and not for "Boat Design". Rhino 3D would be what I would try. They have free demo. (Search in this group for Rhino and CAD) Have you looked at a glass MacGregor 36? http://www.tompatterson.com/Sailing/Sailing/Sailing11.html http://www.mv.com/ipusers/pdelnero/MAC.htm http://www.geocities.com/area51/dunes/6187/ http://www.sailboatowners.com/boats/index.tpl?fno=80 They can be found for under $10K. Mat From: "brentswain38" Date: Sat Dec 8, 2001 10:13 pm Subject: Re: origami cats, design book Just take any design for a hard chine catamaran having the displacement you expect,and make a model , then take the plate shapes off the model , or obtain the plate shapes by computer.For plate thickness just look at other aluminium catamarans of the same size and displacement .You can then make an origami model to double check to see how things work out. For a copy of my book please send $20 plus $10 for overseas airmail to suite#427, 1434 Island Highway Campbell River BC Canada V9W8C9 Brent Swain From: "dr01allen" Date: Thu Dec 13, 2001 7:34 pm Subject: plastic hulls I've just found a source for 4X8 sheets of high density polyethylene. thickness ranges are from 1/8 to 1/2". I'm thinking that these could be welded to produce a single sheet and just as good for folding and bending as metal. they may need some transverse stiffeners of wood or PVC. no epoxy, no painting, minimal maintenence, an inherent non-wetting surface, and one that should stay relatively free of hitchhikers (never seen a barnacle on a PE jug). cost looks about the same as marine plywood, < $40 for 1/4" and < $80 for 1/2". any concerns? da From: Stephen Wandling Date: Thu Dec 13, 2001 9:53 pm Subject: Re: [origamiboats] plastic hulls I suspect there would be a lot of interest in this technique on the Smallboats forum on Yahoo. From: "dr01allen" Date: Fri Dec 14, 2001 2:12 pm Subject: anyone tried Form Z anyone tried Form Z for hull design? it has an 'unfold' function that looks interesting. according to their website, where the unfolding starts is selectable by the user. it'll also add connection tabs. I downloaded the demo, the user interface is a bit awkward and the help function is minimal. I haven't worked through the manuals yet, maybe they'll help. da From: martin brumhauer Date: Fri Dec 14, 2001 3:51 pm Subject: Re: [origamiboats] plastic hulls My father has a Folboat brand poly boat. It is a 10' row/outboard boat constructed of ~1/8" sewn sheets that is a true origami boat, as it folds up and unfolds with a one piece hull. The hull is held in shape with the removeable seats. These are currently being made, and for those unfamiliar with them they are a boat that folds to ~4" thick by ~20" high by the ~length of the boat. (You may have seen them strapped to the sides of motorhomes) This boat takes some getting used to as it is flexible, i.e. when you stand in it you can feel and see the bottom flex out under your feet. One advantage of this, which I don't know how it would work in a large boat, is that the boat rides very smooth as it 'gives' and flexes with a chop. This give combined with the toughness of poly allows you to beach the boat on a rocky shore with no damage or hard impacts. The boat is also very stable, as the flexing localizes the impact of weight instead of 'rocking' the boat. One thing to keep in mind is that HDPE and UHMW have poor tensile strength, and little resistance to flexing. HDPE also does not have very good impact strength compared to UHMW. I would think a larger boat would require construction similar to a traditional wooden boat, with a 100% load bearing structural backbone/skeleton planked with the poly. As far as a small boat, anyone considering an inflatable should check out a folboat first. JK From: "ravensoars2001" Date: Fri Dec 14, 2001 8:42 pm Subject: Re: plastic hulls I have had good results welding UHMW for bow rollers etc. The technique requires pressure and precise timing to be sucessful. A consideration in attempting to join larger sheets. An overzealous forklift operator just bent a pice of 2"X 2" square tube around the curve of the aft quarter of my 36'. The hull shows no sign of impact or distortion whatsoever. I have little confidence in any plastic to resist this type of mechanical load. Given the carnage in Porpoise Bay after last nights storm (1 wood boat sunk, several glass boats washed up and damaged, aluminum floats holed etc.) i would be inclined to perform extensive destructive testing on any welded plastic hull form prior to investing money in a whole plastic boat. Imagine the backing plate system you would need under a mooring bit for example? What about mounting pintles, mast steps stern tubes etc? That said, cross linked plastic and royalex in canoes is a well proven system for the product. rt From: "r_biese" Date: Sat Dec 15, 2001 4:33 pm Subject: Hi all out there I need your help Me Ronald I've been from France to Australia with a wooden 45 double-ended ketch restored from 1912. I'm not a wood nut but IS THERE any longkeel ORIGAMI design not the fast type but blue-water a deep, large and fat seegoing Lady sorry but like the BBW's singing Jazz or Blues Lady's i like to die for....... If anybody can proof a fin kell as seeworthy and with huge space .... I let's discuss a wishbone schooner...... as I did it in Australia, singlehanded... so something 35' to 40' to sail, and to live on but not a ::: kit Ronald to type on a french keyboard well me born in Germany went to school fro UK to ?? and now living in France From: "Doug Barnard" Date: Sat Dec 15, 2001 9:49 pm Subject: Van De Staad vs. Origami So I've been perusing materials from the Van De Staad Design firm, and learning about another form of "high speed" steel construction. I purchased his rather expensive book, (suitable for coffee tables, not construction), some fairly uninformative study plans, and (the gem), his booklet on assembly techniques. Basically, long strips are developed from the hull design, and built upright in a custom cradle. For the purposes of discussion, I'll make the distinction between the "split orange peel" of origami, and the strips of VDS (Van De Staad). I think that both methods have more in common than not, and, as I've said before, it still amazes me that in the whole wide world, only two dudes have said, "Hey, I need a strong boat and all, but does it have to take so long to build?" In the case of my trawler design, the VDS method makes a lot of sense to me. As a 48' trawler is pretty damn big compared to a 35' sailboat, this would mean that I have smaller pieces to deal with. In humble apology to those that cheer the modular method, I'm hoping to avoid using any kind of heavy machinery to deal with the hull during construction. The cradle will allow me to better align the plates, and to check them against the Table of Offsets. I find the idea somewhat scary of trusting my computer drafting and metalworking skills so completely that I'd build the two halves of the hull independent of each other. Imagine if they didn't fit together! Yikes! Here's what I don't like about VDS: He doesn't seem to use longitudinal stringers, and (according to my study plans) requires transverse ribs every 1'4". All of the photographs that I've seen don't have the ribs or the stringers in place, so if anyone can clarify this, it would most appreciated. His hull plating steel is 4mm (~5/32"), somewhat less than 3/16". Assembly-wise, he builds a full cradle that has a brace on top that stretches from side to side. I don't know about you guys, but I like to have Mr. Leverage working on my team. Trying to bow out the long strips could be very problematic. I could see building the support frames like staging, and doing it a row at a time as I worked up the hull sides. Start with the keel, and get that upright. The next stage would be a support structure for the large chine plates and stem. The tops of the chine plates would be initially joined on to the stem, and allowed to extend out, resting on the staging. The plates would be gradually walked inwards, welded to the stem as they came together. All hull plates would run long, so that they would be cut flush with the transom when the hull had been pulled together. Once that is together, the staging would be built up a row to support the knuckle plates. Similar to the chines, they would be attached at the stem and bent back into position. I might even be able to use a regular come-along to get the plates together, as the long lever arm would greatly assist me. Same deal with the sheer plates, and the bulwarks. The build-as-I-went staging would also be handy for scaffolding, and when the hull was complete, a sturdy cradle to support the boat during the rest of construction. I'm thinking that 2X4s on a base of railroad ties would be suitable for this staging, with plywood tops and suitable cross-bracing. As for stringers, I'm thinking like 3/8" X 1", every two feet up the hull sides. Commentary, please! From: "brentswain38" Date: Tue Dec 18, 2001 12:02 am Subject: Re: Hi all out there I need your help --One of my 31 footers was done in a single full length keel version. One of the problems with a full length keel is that the area in the aft end of the keel amounts to roughly 300 lbs of extra steel in the stern of the vessel where you need the weight least.Being an area where weight should be kept to a minimum , it's useless for storage . and impossible to get into and paint or maintain properly. Another problem is that you have to fit the full length keel to the hull from the outside before cutting away the centreline, whereas with the shorter keel you can simply cut a hole and shove the keel through. My last boat had a full length keel and had far less directional stability than my current twin keeler or the newer , long fin keelers. Directional stability has far more to do with the hull shape than the length of the keel. My book describes this in much greater detail. Full length keels have no real advantage over long fin keels,in terms of seaworthiness , and have many disadvantages.While building an origami boat with a full length keel is light years easier than doing it the traditional way, it's quite a bit more difficult putting the keel on. Brent Swain From: "brentswain38" Date: Tue Dec 18, 2001 12:13 am Subject: Re: Van De Staad vs. Origami Doug Chines have far greater stiffness than longitudinals, they can be similar in strength to fully welded longitudinal bulkheads. Divide the space between chines into equal spaces not exceeding about 16 inches and put your longitudinals there. If you plan to foam the hull( and it would be foolish not to) Angle irons of about 1 inch by 1 inch by 1/4 inch are far stronger structurally than flat bar.Buying wheelabraded and primed steel eliminates the old problem of cleaning behind the angle irons before painting. 5 mm plates of the size you describe ar quite floppy and you'd have no problem pulling them to shape as log as there wasn't too much twist in the ends. This method requires far more welding , grinding and fitting than origami, but may be neccessary for the shape you seek. Brent Swain From: "brentswain38" Date: Sat Dec 22, 2001 11:57 pm Subject: Re: plastic hulls --Steve What is your souce of 4x8 ft sheets of poly ? I could use a bit. Brent Swain From: "greenguy2ca" Date: Sun Dec 23, 2001 6:21 pm Subject: Rust In building the steel boat supposing there has been some rust because the original primer coating was scraped off or you did not property wire brush and coat a weld on the inside. Would the process of epoxy and paint fix that or will you have a rust through point at some point in the future. No matter how thorough you hope to be I am sure that there is going to be some unprotected steel somewhere in the boat particularly on the interior underneath the angle iron or where ever. Thanks From: "dr01allen" Date: Mon Dec 24, 2001 6:49 pm Subject: Re: plastic hulls it's in an industrial maintenance catalog at work. I'll have to wait until after the 2nd to get the details. da From: "alex_christie" Date: Thu Dec 27, 2001 4:46 pm Subject: new photos of 36 footer Dear Group, I have posted 2 new photos showing good view so the 36 foot fin-keeler, Moonraven for your viewing pleasure. Alex Christie From: "brentswain38" Date: Thu Dec 27, 2001 10:41 pm Subject: Re: Rust --We've never worried much about the smaller chips and it hasn't mattered much. Many of the new epoxies (like bar rust 235) are quite surface tolerant when it comes to small amounts of rust.I've been told that newer ones are coming out which are even more surface tolerant. Larger missed spots should be touched up at the first opporunity, or, if they get rusty, cleaned up with the grinder and primed. If you have most of your welding done and it's the wrong time of year for painting, another coat of primer should hold the fort until spring. 3/16th plate , left bare and damp on one side , will take roughly 15 years to rust through , if there is no electrolysis happining. Brent Swain From: "alex_christie" Date: Fri Dec 28, 2001 4:47 am Subject: Companionway hatch design and construction Bert and Jan wrote me asking about the companion way hatches on Moonraven. My reply to them couldn't be sent because of a problem with their yahoo mail, so I'll post it here, and others perhaps would like to add anything they know about hatches on Brent boats. I've put their question here, an old response from Brent from the archives, and lastly my two cents worth: --- bertandjan wrote: > Alex, > Thanks for the pics of Moonraven... > I wonder how much the 36' fin keel version draws?? > And, did you build the sturdy looking companionway > door from scratch? What did you gasket it with? > Interested in its design.... > All the best, Bert (and Jan) Eggers.... > snowy Saginaw, Mi Dear Bert and Jan, The companion way hatches on Brent's boats are one of the most well thought-out structures I have seen on a sailboat, and it has often made me wonder why people use anything else for metal boats. The aft bulkhead of the pilothouse is slanted forward a little more than most boats, to begin with. When entering the boat, this allows a person to walk down into the boat without stooping (depending on your height), and avoids the need to have a sliding companionway hatch on top. A lip of stainless is welded to the bulkhead all around the hatch entry way, making a good mating surface for the neoprene gasketing of the aluminum hatch to seal against (the hatch door itself has a lip which fits around the outside of the lip on the boat --- I'd imagine this would make it very difficult for thieves to get much gap to pry open the door). There are two pintle hinges on one side, and a simple lever latch on the other which dogs down the hatch very securely. It looks from the photo that the Moonraven people have put two levers, though I doubt it would be needed considering the stiffness of the aluminum over such a short distance. Some folks put small plexi windows or a portlight in the door, but in Moonraven's case they put it next to the door. The door is not heavy, being of aluminum, so does not present a danger to the occupant by swinging. Because it is on pintle hinges, it can easily be lifted off when the door is open, but cannot be slid off when the door is dogged tight (nice if you are upside down inside a rogue wave...). Being a scaredy-cat when it comes to pondering deep sea passages, I like this "submarine" style of door! I have also noticed that Brent doesn't bother with opening ports on his own boat, simply plexi properly bedded with goop and a neoprene gasket. He has achieved sufficient ventilation via the forward hatch (the bow usually being in the wind at anchor), flowing out the aft hatch and main cabin hatch. I think his philosophy is that if it can't open, then it can't cause you grief in a storm. As for draft, Brent wrote about some of the basic specs in (I think) message #375 a ways back. I will copy and paste here what he wrote: "The 36 is 35 ft 5 inches overall, 29 ft waterline, 5ft 10 inch draft with the fin keel, 4ft draft with the twin keels , 17,280 lbs empty, full depends on how much of a packrat one is. 5700 lbs keel weight, (4500 lbs lead ballast, 1200 steel ) Most people go for a 46 or 47 ft mast stepped on deck. The 31 footer is 31 ft overall, 26 ft waterline, 3500 lbs lead ballast , 4500 lbs total keel weight, 4ft draft twin keels , 4ft 6 inch draft single long fin keel . Most people go for a 40 ft mast stepped on deck . Both boats have 3/16th inch hull plate , 1/8th inch deck, cabin cockpit and rudder plate, 1/4 inch keel plate and 1/2 inch on the bottom of the keel. Altho I've built a 36 ft hull in ideal conditions, and shell ( hull deck cabin cockpit , keels, skeg tacked together in 6 days, it usually takes 2 to 3 weeks ." I am planning on building a 40 foot Swain hull, which I believe draws 4.5 feet with the bilge keels, but I'd have to look at my plans again to find out. Of course, being steel, there is some variability in the choices you can make for draft simply by adding on. Myself being a former river canoeist, I'll have to simply get used to drawing that much, and be thankful that I can dry out on a mudflat if I miscalculate when anchoring. Regards, Alex Christie From: "Douglas Pollard" Date: Sun Dec 30, 2001 2:36 pm Subject: Refrigeration Hi Folks, This is not Origami so I guess its off subject but I hope it may be of some use to those who build and go off cruising in boats Here 'is a little stunt I learned while living aboard in the tropics. Most you who move aboard their boats, will at some point wind up in hot weather and will install some sort of refrigeration. I put in engine driven refrigeration that is also driven by a one horse electric motor at the dock simply by switching the belt from engine to motor. If you work on your own unit you will need a vacuum pump to pull it down to - 30" of mercury. Well I bought a hand vacuum pump at an automotive store that is used by mechanics to check vacuum diaphragms and such on automobiles. These pumps sell for about $45.00 US. One of them will pull about - 25 inches of mercury, not good enough for refrigeration. So, here is how I used mine. I have a shut off valve in the low pressure side right next to my refrigeration compressor and one just before my expansion valve in the high pressure side. Shut off the valve on high pressure side of line and use your compressor to pump low pressure side over into the high pressure side and bleed off high pressure side. Warning: I would not do this on a new installation as there may not be enough oil in the system to lubricate the pump and to pull down a system in use I would not let the pump run for an extended period even on an already used unit. You should be able to pull down the low side to about -28 inches of mercury [less than perfect] Shut off the valve on the low pressure side. Now you have a vacuum on the low side and atmospheric pressure on the high side 14 psi approx. Here is where the hand vacuum pump comes in. Using the hand pump you can pull this side down to about -25 inches of mercury,takes a lot of pumping. When you open the valves between high and low sides, you will have about -26 or -27 inches in the whole system. At this point you can fill your system. it will be less then perfect and you may experience a certain amount of icing up in your expansion valve but you have cold beer. Now here is where you have to let your conscience be your guide this is not legal in the US and I'm not sure about other places. Before you fill your unit, you could put some refrigerant in the system and pump it out by the same above method. By doing this a couple of times you can eliminate any moisture or air that may be in the unit. Every time you do this it gets better. I don't recommend doing this but if you were a long way from help it would be something I would at least consider as even a little freezing in the expansion valve is a pain in the neck. By the way I use the 134 a refrigerant that they sell in automotive stores in my system. Apparently it must not be to hard on the atmosphere as they sell it to people who have no means or knowledge of refrigerant recovery systems. It is cheap and puts refrigeration back in the hands of the amateur. The only drawback is it takes longer to pull your system down when in use. So you have a longer engine run time. It takes about 45 minutes run time to pull down my refrigerator. I have a hundred amp alternator and that run time charges my batteries as well. The problem is you get sloppy about burning lights and using the single side band radio and all of this is wear on your engine. We did without refrigeration about five years but I finally gave in, as my wife was about to mutiny. I'll have to admit it didn't take long to acquire a taste for cold beer again. So you boat builders out there may want to keep this in mind for a future day when you will also give in. Doug Pollard