View Full Version : Hybrid Construction
09-25-2004, 09:31 PM
I guess that I can’t decide between “traditional” and “modern” boatbuilding methods, and have been wondering about combining some of the best features of each. Cold molded veneers may be used as a last resort to rescue old carvel planked boats, but I have never seen a description of new construction using cold molding over carvel planking (as opposed to cold molding over strip planking). I would appreciate comments and suggestions from experienced builders about the following proposed construction method. Final design is not chosen, but I am thinking about a traditional cruising sailboat in the 35-foot range.
1. Upside-down hull construction.
2. Laminated or steam bent frames over molds at each station, i.e., Herreshoff method.
3. Planking with 1/2” or 3/8” stock riveted or screwed to frames.
4. Thickened epoxy to fill small gaps between planks, prior to fairing and application of diagonal cold-molded veneers to achieve the design hull thickness.
5. Apply glass below the waterline for abrasion resistance
6. External lead ballast
In suggesting this method, I’m making the following assumptions – please let me know whether or not you think they’re valid:
1. Spiling and fitting planks would be more pleasant and interesting than stripping.
2. The fit of the inner planking could be a little less precise than traditional full thickness planking with caulked seams.
3. The inner planking layer would weigh less than a similar thickness of strip plank with epoxy.
4. The thin inner planking would be easier to bend and fasten to the frames than full thickness planking.
5. Planking stock of 3/8” or 1/2” would be thick enough to result in a fair hull before the cold molding is applied.
6. Butt blocks and shorter stock could be used more liberally on the inner planking since the cold molded layers would provide some dimensional stability.
7. If the planks were fit dry to the frames, one wouldn’t have to deal with removing epoxy from the inside of the hull during planking.
8. The interior of the hull would have a more traditional appearance than one gets with strip planking.
9. The frames provide a structural element for attaching furniture, ceiling, and bulkheads.
10. Plans for a traditionally built boat could be used without significant modification for cold molding, at least as far as mold shape and spacing are concerned
11. The resulting hull would be stiffer than a similar boat that was traditionally planked
Should the inner planks be glued to the frames, or just dry fastened?
Would rivets or screws be better to fasten the thin inner planking to the frames?
Pros and cons of laminated vs steam bent frames?
Difference in time and materials cost for this method vs strip planking?
Thanks in advance for allowing me to tap into your collective wisdom and experience.
[ 09-27-2004, 10:26 PM: Message edited by: Dave Lesser ]
09-25-2004, 09:36 PM
Sans the epoxy, this is pretty much the method used to built Gypsy Moth 1V?--Chichester's round-the-world yawl. variants have been successful. It's a variant of double-planking, with the exterior layer a seamless veneer.
09-26-2004, 12:15 AM
A few thoughts......
That's a lot of work. While it depends on the size of the boat, I don't think you really need both frames and the outer layers. The trend has been away from transverse framing toward longitudinal framing for some time now, with interior structure and a few well placed bulkheads or ring frames where needed.
Depending on the frame spacing, 1/2" material may or may not fair in easily. I would think 3/8" is too light for anything more than a canoe or smaller skiff. The smmaller stuff is harder to handle at every step of the project. There's a reason 3/4" is so popular- it will easily span 3' and remain fair, and it's easy to get out of readily available standard "1 by" stock. How much more time to mill the smaller stuff?
Nothing adds strength faster than increasing total hull thickness, and the weight penalty is usually pretty small. Calculate out the difference and see. Frames/ribs only get in the way of a nice clean interior, and make finishing more time intensive.
I would glass the entire exterior- to stop at the waterline is a false economy and can lead to issues down the road as the surface works and wears unevenly. The added weight and expense is insignificant in the scope of the total project.
Try to come up with a list of priorities- cost, time to build, level of finish, longevity, resale, weight, etc. Once you've established the dominant criteria everything else will come into focus, and the choices will be more obvious. Good luck!
09-27-2004, 09:25 PM
Thanks for the feedback. After a little more research, I have learned that Paul Gartside uses a variation of my proposed method in his shop in British Columbia. Anyone have experience with his boats?
09-28-2004, 04:09 PM
To try a different approach altogether, the first thing that comes to mind reading your question (which appears to have been well laid out ahead of time and suggests a program that seems like a good one) is this: While the WB site, and the forum in particular, are good resources to have at the center of any building project (amateur OR professional,) it is a really bad idea to center any project around feedback from the forum (I don't mean to sound preachy here, I'm just making sure we're reading from the same page).
Dave L, don't take this as a slight, it's clear from your post that you're not just blithely diving into things here, but from one of the responses you got I am motivated to add the reminder that the hierarchy of references goes: experience; professional advice - including published references; opinions of friends/folks at the yard; opinions of anonymous forumites. The only truly reliable use of the forum is as a hub for meeting other like-minded folks whose opinions you can share in-person. The exception to this are the FAQ threads on the grounds that they contain advice that has been peer reviewed, not gospel, but definitely worth consulting.
So, to balance the measure, I'm on side and think your proposed method is sound. If I think it's crazy that you'd prefer the fairing of planks to the fairing of strips, I'm not gonna argue with you about it.
And if you figure how to keep a hull together that's got carvel planking over stringers with no frames, you better patent it 'cause my few experiences have taught me to consider that an impossibility - although it sure would lighten a hull up.
I think you should consider a Gartside design, he's got a timeless sense of lines, cruises in boats of his own design and he's messed around with epoxy.
And, since the molded outer skin's going to hide the location of the fasteners on the inner skin, I'd consider gluing planks to frames with 5200 or epoxy, or blind fastening through the frames. Repairs on this boat will be with a router and circular saw, and so buried fasteners would be a potential nightmare.
To combine carvel planking with cold molded is the method used in Turkey to build traditional boats of my design. They seem to favor it. With behind them a long tradition of boatbuilding
Pic 1 again http://www.tantonyachts.com (http://www.tantonyachts.com/Pac00143_small.jpg)
Pic 2 http://www.tantonyachts.com (http://www.tantonyachts.com/Pac00120_small.jpg)
Pic 3 http://www.tantonyachts.com (http://www.tantonyachts.com/936Prof_small.jpg)
09-28-2004, 07:58 PM
Hey YMT, your pics are coming up kinda small. Can we fix that?
09-28-2004, 08:05 PM
Would one of you kind gentlemen please explain to me the advantages, any advantage in fact, of the proposed construction method? I seem to have missed something.
By covering the traditional plank-on-frame caravel boat with veneer and glass you not only greatly increase the labor and materials expense, but also most likely increase the weight beyond what it could be. You also eliminate any of the repairability advantages of traditional construction by covering the fasteners and binding the planking together. These fasteners, I might add, now only serve to weaken the planking and frames, create potential electrolysis issues, add weight and expense, and consume labor.
On the interior, the transverse frames make it more difficult to finish the hull shell, add weight and expense, and are less effective structurally than simply increasing the entire hull thickness evenly through-out the shell. Plus, in those few spots where the frames don't end up 100% bedded against the hull dampness and then rot can get a start in the hull.
It seems to me one would be better served by either going with a traditional plank-on-frame hull, and enjoying the advantages there-of, or going with a more modern interpretation of engineered wooden construction. To combine the two only seems to nullify the advantages of each, with no benefit gained in return.
But others here are smarter, with vastly more experience than I have, so I look forward to learning and improving my knowledge base! What would the advantage of the proposed construction method be? Thanks in advance1 smile.gif :cool:
[ 09-28-2004, 09:50 PM: Message edited by: Kev Smyth ]
09-28-2004, 08:08 PM
Conrad, read the post. Dave L. states pretty clearly what he thinks are the advantages/disadvantages are.
There's no debate, just you being contrary.
Pic 4 http://www.tantonyachts.com (http://www.tantonyachts.com/Pac00142.jpg)
09-28-2004, 08:36 PM
The initial list of "advantages" appears to be based on assumptions, not experience. For example, thinner planking will be harder, not easier to fit and lay fair- with a thinner edge the fit must be perfect across the entire width, not just at one point. Thinner planking is less likely to lay fair, more difficult to handle, and more likely to snap or split than traditionally sized planks. And if the fit isn't as good as traditional construction with caulking would require, then the epoxy slathered on the outside will leak through, complicating the interior finish process. Finally, if one hasn't built a boat before, spiling and fitting will be much slower than stripping, and often requires two people to proceed at an acceptable rate.
Shorter stock and more butt-blocks isn't a good idea- the shorter planks won't bend in as fair as longer continuous planks, and much more time and material will be required. And the frames absolutely must be glued to the planking. Since the fastenings are covered, frame replacement will be a chore. It would be best to do everything possible initially to prevent the possibility of rot.
A more traditional looking interior is the one aspect one can't deny- but why not just build a traditional boat, and do it properly, retaining all the advantages?
Having been through this debate myself I've (obviously) come to the conclusion that it makes no sense to mix the old and the new. Each works very well when done properly, but there's no real advantage of mixing and matching. What is forgotten in the discussion so far is the immense amount of time required to build an even somewhat traditional round bottom design in the 35' range. Anyone working on a time and expense budget should focus first on this fact. Traditionally built, this is a 6-10,000 hour project. Do you really want to add a couple thousand more hours with all the extra layers, epoxying, fairing, etc.? How long are you planning on living? How much of that time do you want to spend sailing the boat as opposed to sanding it? ;)
[ 09-28-2004, 09:47 PM: Message edited by: Kev Smyth ]
Pic 5 http://www.tantonyachts.com (http://www.tantonyachts.com/Pac00211.jpg)
09-28-2004, 08:39 PM
Hey YMT, that's got it. You rule.
09-28-2004, 08:41 PM
And Kev Smyth, you've been Scotted, why are you here?
Pic 6. Hybrid construction. Design #936. Drawings. Page 6. Catalogue no.936
09-28-2004, 08:45 PM
Originally posted by buhmkin:
And Kev Smyth, you've been Scotted, why are you here?Take this to the bilge or private mail- everyone here except you seems to understand the accepted common courtesy. :(
09-28-2004, 08:47 PM
You're STILL here?
09-28-2004, 08:52 PM
Originally posted by buhmkin:
You're STILL here?And I'll edit to add, Kev Smyth/Conrad, it's your lack of understanding of common courtesy that got you Scotted, so dry up and move on.
09-28-2004, 09:00 PM
Originally posted by buhmkin:
You're STILL here?Why yes, Eli, someone has to do more than just complain about others. :(
I've offered quite a bit of information, admittedly from my perspective, on various aspects of the construction method under discussion. The topic originator may eventually agree or disagree- it is, after all, his project, life, and choices. And variety is the spice of life, eh? ;) But I haven't read much from you that expands the subject at hand. You sadly seem more interested in attempting to diminish my credibility and ideas instead of offering your own suggestions. That's Dave's loss and your discredit, but really has no impact on me.
As suggested before, why not take your snideness to the bilge, and focus on the topic at hand here. Stop complaining, and instead offer and defend your opinion, based on your experience. :cool:
[ 09-28-2004, 10:36 PM: Message edited by: Kev Smyth ]
09-28-2004, 09:13 PM
Ahhhh, yer still here.
09-28-2004, 09:40 PM
Dave Lesser ---
"The devil is in the details" or so the saying goes.
The outside layers are effectively sealed by the cold molding and the glass.
The inside layers are not sealed so they will expand and contract as their moisture content changes.
There is a good chance that your boat will pull itsself apart. There is a good chance it will not.
09-29-2004, 12:50 AM
Thanks to all who have taken the time to post thoughtful replies. I didn’t intend to stir up a hornet’s nest. I have no boatbuilding experience except for a 9’6” Nutshell pram, but I have read everything that I can about design and construction for many years. So, I’m certainly not speaking from experience, just trying to clarify some points that I may have read about but don’t fully understand.
The reason for suggesting thin fore and aft inner planking would only be to prevent the hull from exceeding the design thickness after applying the cold molding. I can imagine that the thin planking would be harder to fair if the frames were spaced too far apart.
One of the complaints that I have heard about strip planking is that it takes a long time to remove epoxy from the inside of the hull. I had hoped that carvel planking the inner layer would prevent that step. Also, if the “carvel” planking were the same thickness as the strip planking, I would assume that it would be lighter without all the epoxy used in stripping.
Kev Smyth, I appreciate your concern about adding to an already enormous undertaking. Although I would enjoy the building process, the goal is to get to sailing. But once the boat is in the water, I would like to be able to minimize the time needed for maintenance. Hence the attraction of engineered wood. I know neither method is maintenance-free.
Yves, thanks for the photos. I enjoyed looking at your designs.
Buhmkin, how does a newbie to the forum evaluate the credibility of the advice that is offered? It would be nice if the user profiles included a place to post a resume with information like: Who is a professional, who is an amateur. Number, type, and size of boats built. Number of boats still floating. Formal training or certification, etc.
Mike, thanks for your comments. I ran across Cecil Borel’s site a while back. It looks like a fantastic project, and gives some idea about the amount of work involved. I think that he may have been one who complained about the time needed to remove the epoxy from the inside of the hull.
George, your point is well taken. That is the kind of concern that I would want to resolve before devoting years and fortune to such a project. But, if one is strip planking, is the inner layer completely encapsulated with epoxy? Would encapsulating the frames as well as the planking help to eliminate this problem? Are there ways to “stabilize” wood without encapsulating it? Is that what CPES and similar products are intended to do?
If there is any consensus so far, it seems like most would use epoxy or other adhesive instead of rivets or screws to fasten the inner planks to the frames. Now we’re getting somewhere.
09-29-2004, 01:52 AM
Dave- my apologies for any controversy that follows me. Some here apparently have a hard time separating their dislike of my conservative politics, appropriately expressed down below in MNBR, from what goes on here. :rolleyes:
If you're at all handy with a calculator and have some time I think you'd find a lot of your questions answered by Dave Gerr's book "Boat Strength." He has very cleverly laid out a system for figuring the scantlings of any size boat you may have in mind, for a wide range of materials and techniques. It will also allow you to convert the plans for any design from one construction method to a variety of others. All of the scantlings given are toward the heavy or conservative end of the scale, and very appropriate for a cruising boat. In many cases that I've worked through they exceed the old ABS standards for engineered panels by a generous safety margin. Principles Of Yacht Design by Larsson and Eliasson is more technical and heavier going, but still doesn't require a super-computer.
If I were to build a large engineered wooden boat today I'd do it with strips and urethane glue from a tube- one of the less expensive Home Depot urethanes. I hear the newest Tite-Bond is getting rave reviews, and cleans up very easily. I'd buy a nail gun and hire a high school kid. Then I'd put a layer of heavy glass/epoxy on the exterior and seal the interior with epoxy once all the structure was in. Glass in some bulkheads, bunks, etc and you'll have a very, very strong boat that's easy and inexpensive to maintain.
You're aware the early strip boats only had paint between the strips and a lot of edge nails or wooden dowels? Some even left out the paint. Epoxy is really overkill here, so if you don't want to clean it off the inside, don't use it. If you think you need it, remember the sheer strength of the foams used in glass boats is only a couple hundred PSI at best, a figure cedar strips with frequent edge nails will easily surpass.
Some nice beveled tongue- and-groove panels, etc. will give the interior the classic look you want while the frameless skin reduces the potential for rot and maintenance issues.
Who to trust? I have 30+ years of building and repair experience mixed in along with a wide variety of careers and business interests. God gave me a good mind, but I'm not a "pro." Mike is a pro, has many, many years of experience building practical, sturdy craft in largely traditional methods, as well as some fancier stuff, and knows a better idea when he sees it. He's used to operating in a cost-conscious environment.
Remember the hull is usually about 10% of the cost and 20% of the labor, so if you get bogged down with it the end of the road can seem a long ways away. Hopefully you're younger than I! Good luck, and have fun! ;) :cool:
[ 09-29-2004, 03:09 AM: Message edited by: Kev Smyth ]
09-29-2004, 08:53 AM
I believe my example--Gypsy Moth lV--was done with conventional planking followed by several layers of diagonal, glued veneer, mainly as an alternative to double planking. The effect is more or less the same--no seams through the hull, and with the diagonal veneers, the the grain lies along the stress lines.. An exterior "shell" of cold-moulded veneer would be supported by the inner planking as if it had a series of strong, longitudinal ribs. This could be very tough indeed. As for why ribs?, this is mainly a construction issue. It gives you a place to hold fastenings while the planking is installed, as well as interior attachment points, spacing for ceilings, etc. The glued veneer would ultimately make the fastenings redundent. Proper bulkheading makes the ribs redundant. Overall, it would seem to be quicker and easier to use relatively thick planking than lay up the equivalent in cold-molded veneers, while the exterior done in glued veneers is watertight, torsionally stiff, and waterproof. All in all, it is an interesting concept. The main problem I see is thinking through the cricical joints--hull/keel and deck/hull, in a way that makes structural sense.
09-29-2004, 10:50 AM
"As an engineer, George, explain why plywood is not banned from building boats?"
I don't understand your question, but ...
I don't think there is any group that is in charge of banning materials.
Dave, will the backbone have a rabbet? and if so will you glue the planks into it?
09-29-2004, 11:21 AM
Yes, the backbone would have a rabbet, and the planks would be glued into the backbone. The inner planking would essentially be standard carvel, except that it would be attached to the backbone, floors, and frames with adhesive instead of mechanical fasteners. The cold molded layers over the inner planking could follow into the rabbet, or could extend to cover the rabbet, depending on how deeply the rabbet was cut.
09-29-2004, 03:55 PM
The construction proposed is very much like placing thick veneer (the inner layer of planking) over plywood (the cold-molded veneers).
Some people have problems with doing that even in a stable environment like a house. Other people have no problems in an unstable environment like in a boat.
I don't see enough information in the original question or in the resonses to advise other than I have.
09-29-2004, 06:29 PM
Well Dave L, I guess you're a newbie no more.
It's funny you mention profiles, have a look at the ones from the guys who've responded here.
Now weigh the length of the responses against the evidence of credibility that's available in the individual profiles. Note there seems to be a relationship here, so that more of one equals less of the other.
Well, then there's the question of whether or not the profiles say anything about credibility, but now we're getting into formalist WBF analysis and I'm no Eichenbaum.
Originally posted by Dave Lesser:
Yes, the backbone would have a rabbet, and the planks would be glued into the backbone. The inner planking would essentially be standard carvel, except that it would be attached to the backbone, floors, and frames with adhesive instead of mechanical fasteners. The cold molded layers over the inner planking could follow into the rabbet, or could extend to cover the rabbet, depending on how deeply the rabbet was cut.And if you epoxy instead of caulk between planks you'll have a fully glued up hull, for all intents and purposes a glued strip planked hull only with 'strip' planks wide enough to require proper spiling for fit. And then veneer over that. Sounds like a plan to me although wouldn't you still want to use plenty of fasteners as well? I would. Not that I'd know for sure anymore than most of the other contributors to your thread. In principle there doesn't seem to be anything controversial about gluing veneer over glued planking such as Gartside is doing. But although you may experience the satisfaction of learning traditional techniques it does sound like in the end you're going to be up to your alligators in epoxy and fairing.
09-30-2004, 10:18 AM
Sounds like a visit to Paul Gartside might be in order before proceeding further. I would assume that he would be open to consultative visits, especially if one is considering one of his plans. Does anyone have any first hand experience?
09-30-2004, 12:00 PM
My 2 cents.... every time you put a layer of wood over the frames, you're building another hull. It's never quick and it's never easy. If you're veneering you have to "plank" the hull probably 3 or 4 times.
If you're going to carvel plank, and then veneer, you're going to be building that hull for a long, long time.
In my view, it's easier to do it just once. Either build it as a plywood/veneer boat, or build it as a carvel planked boat.
My vote (depending on the boat of course) comes from the 40ft wooden ketch I sail. It's 55 years old and is sound. It doesn't leak (less than a quart a week at the moment, in harbour) and to my knowledge has never had a plank off or replaced. BUT IF IT DOES need a plank off, it's not really that complicated -- you remove the old one, use it as a pattern, make a new one and fasten it back on. Not that big a deal.
If you're going to carvel plank anyway, you might as well do it traditionally and leave it at that. You'll get to sail it that much sooner, and the hull will keep the water out just fine!
09-30-2004, 12:25 PM
I have stayed out of this discussion because I'm just an amchoor here but.........another son is working on a project that I am currently putting together with a well known designer.. The construction metod is strictly my own so that he has no responsibility if it breaks or crashes and burns......but I believe that it is applicable here....I will say it and go away......
The boat is a 32 originally conceived as a plywood lapstrake shallow water craft with centerboard. My son is a "Forest Ranger" in South Carolina and as such dunno make much money, but he likes what he does.....rides a bike, no car and what he wanted was a liveaboard without really expensive material. One item that is readily available are Looooong lengths of virtually knot free douglas fir. The first palnks were purchased and I had him work several weekends cutting the planks in hald to form two one and five eigths wide planks by 3/4 inthes thick...by however long the boards were...then he sliced (sawed) the planks to make one and 5/8ths by 1/4 inch planks...or a hair less.....then the planks were scarphed to make them 34 feet long and then the scarphs were staggered and the planks were laminated together to make something about 1 5/8ths by 3/4ths by 34 feet long, then tongue and grooved.....and since the boat was to be planked with FLAT plywood the planks slid together absolutely beayutiffully.......and then..after each plank "system" was glued in place, and bevelled for the next "plank"...the next was installed...so far only two "strakes are in place but the result will be a planked boat, and will have xynole in and out in epoxy and I betcha its gonna be just fine.......
09-30-2004, 12:52 PM
Yeah Dave, I think the Gartside site is maintained inpart to encourage folks to get in touch.
Okay, Oyster, if you're gonna use construction grade verticle siding (the v down the middle gives it away, even after you've filled it with caulk) to build dinghies, that's fine. But don't pretend that your 'four or five years' experience doing this makes you an authority.
What do you got there, fir, one ring to the inch? Quality.
Once again, that's not an attack, just lettin' the facts speak for themselves.
09-30-2004, 01:53 PM
Unbelievable- I'm still waiting for him to contribute something positive, other than his criticism of everyone else, all of whom have more experience than he. :rolleyes:
Eli, ya shoulda worn the respirator during the early years... :eek: tongue.gif
Very clever, Mike! Kind of an "instant lapstrake" boat! I like it! smile.gif :cool:
[ 09-30-2004, 02:54 PM: Message edited by: Kev Smyth ]
09-30-2004, 02:37 PM
Spruce should be OK for a trailer boat. We can get the same stuff up here in Western Red Cedar- clear 16' lengths. (Niener, niener!! :D ) I just never thought of sliding each plank up to create the lapstrake look. It would be a great way to build a base for additional layers on a larger boat too. And perfect for skiffs. smile.gif
What do you think the smallest boat would be where it would make the bend at the bow? It would be great if you could do a 12-14' skiff that way, but it might not make the bend. :(
[ 09-30-2004, 03:39 PM: Message edited by: Kev Smyth ]
09-30-2004, 04:57 PM
I had to copy the whole thing before you come to your senses and delete it:
"Look again, nimrod, at the wood. Niener, niener niener. But also what has happened on this thread ,with the mindset of the bullies in the bilge, surely gives me another reason to forgo wasting my time answering questions. Personal attacks should not be toloerated on ANY BOAT RELATED THREAD, PERIOD"
Oh, I see, there's a Lloyds stamp on the end of that top 'plank', well, I never woulda guessed. . .
To break it down for you nimrod = textbook personal attack, and you're right, so take "Kev" there and head for the glory hole. . .
09-30-2004, 05:57 PM
Actually, if you look it up, a "nimrod" is a "great and mighty hunter," so I think that makes it a compliment! ;)
"In the Bible, a mighty hunter and king of Shinar who was a grandson of Ham and a great-grandson of Noah."
[ 09-30-2004, 07:00 PM: Message edited by: Kev Smyth ]
09-30-2004, 06:39 PM
You gotta be kidding me.
09-30-2004, 06:45 PM
NIMROD became a term of derision years ago on the East Coast of the US.
Meaning became a person out of step, a doofus, a hoople..
If memory serves the cartoon character Bugs Bunny used it quite often.
Yeah, I went to the drive-in once or twice.
09-30-2004, 06:59 PM
Not to mention that whole Semiramus/Cush thing.
09-30-2004, 07:32 PM
Dave: I have been following the thread intermittantly. I went through many of the concerns you raised. For me, strip planking was the technique of choice. I have found some good strategies for removing glue lines and fairing. Many good suggestions came from the forum. Since I have been given much good advice from the forum, I am willing to contribute whatever I may have learned. Please feel free to contact me through the email route, if you would like.
10-01-2004, 04:21 AM
It's against my better judgement to post on this thread which seems to have rather deteriorated into a bun-fight, so I hope I don't get flamed for the one perhaps very obvious thought I have to add to the (original) subject.
I haven't yet built a boat but I have renovated one and I did work in the business for a good few years. (See now I feel like I have to justify my right to reply!) I feel some empathy with Dave's initial, well thought out musings because I too had/have plans to try and build a mid 30's foot strip plank yacht, although I've got so bogged down in housebuilding etc. to try and get somewhere with a shed big enough that I don't know if it'll ever happen. Anyway I spent many hours going over the same thoughts about combining construction methods to try and make it cheaper / easier / quicker, also buying & reading books, and reading and asking the odd question on this forum etc.
What I keep coming back to, and what has been eluded to by Cleek and some of the old gaurd in earlier posts is this:
I just can't believe that all of these designers, naval architects, boatbuilders etc. aren't already doing it the cheapest, easiest and quickest way, seeing as generations of them have had lifetimes to evolve the methods.
I too was seduced by ideas of using wider planks in some kind of "engineered" construction thinking that it must be easier and quicker, but in the cold light of day I just don't think it would be, and probably wouldn't be any more pleasant to do.
If the goal really is more to go sailing than to build (which personally I think a lot of would-be builders are deluding themselves about) then surely the best way to get the hull built has to be to follow exactly a proven design's construction method for strip planking: most likely minimal framing, glued and edge nailed strips the full thickness of the hull, and a layer of cloth & epoxy on the outside if necessary. The overwhelming evidence states that this is the best option for an amateur working short-handed. In addition if you stick to a proven method then people, most importantly your designer, will be happy to help and advise.
A friend of mine built a strip boat and he said sanding off the inside was indeed the worst bit, but surely this could be minimised with careful glue handling?
If the desire to cut and spile planks is strong, why not build a proper carvel hull? Again the design and specifications will be well established, and the experience might be very fulfilling, giving one a boat one can be justifiably more proud of.
As for veneers, there obviously are methods such as those detailed by Gugeon Brothers (sp?) where planks or strips are used under a moulded construction, but the planks tend to be more just to achieve the shape for moulding over, with all of the strength given by the laminated veneers. Also, I got the impression that these methods were best suited to more specialised and experienced builders trying to achieve a particularly strong and light hull, but with less emphasis on ease of building, repairability etc.
Dave, I sincerely hope you get to build your boat, and while all postings on these forums have an element of vanity in them (remember how exciting it used to be if you got a letter published in a magazine?? it's all too easy now :rolleyes: ), I hope I'm actually helping a bit and not just listening to the sound of my own voice.
All the best,
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