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rmann
03-18-2009, 01:54 AM
I am interested in building a canoe or skiff using wood strip construction but without the use of fibreglass.

I recently read an old Western Farmer article about building an skiff right side up - 1.25inx0.25in cedar strips were edge nailed over molds; this was followed by fitting 0.75inx0.24in frames/ribs. No additional sheathing or covering was used other than painting.

I also read an article by Alex Comb "Building a one off wood-canvas canoe" where the planks are fixed to ribs bent over ribbands which in turn are stretched along station molds. The ribbands were removed and the hull was covered with canvas

Is it possible to build a reasonably strong and watertight canoe or skiff using wood strips and ribs without fibreglassing or covering with canvas?

I am interested in further information and general opinions.

Todd Bradshaw
03-18-2009, 03:06 AM
There were quite a few models of canoes and guideboats built that way back in the old days - with lots and lots of very small clenched tacks used at the plank seams. A fair number are still around after 100 years or more, so they seem to be structurally strong enough. It should be understood though, that varnished cedar planking is pretty easy to tear up if you hit anything.

There are custom builders who make one-off canoes (wood/canvas) using the method Comb wrote about. It basically is a way of avoiding having to first build the big, heavy, steel-banded form that most production boats are built on. The trade-off is a lot of time spent clenching tacks by hand.

Thorne
03-18-2009, 08:08 AM
As Todd says, you can certainly build boats like that without epoxy -- but you'll be substituting woodworking skill and top-grade materials in place of epoxy. You may also end up with a heavier boat, and certainly one that can't be left out in the elements like a glassed boat.

What are your skills and woodshop like, what use and storage do you plan for the boat, etc?

If you are interested in traditional building and don't like epoxy, why not build a lapestrake canoe, guideboat or skiff as they were done in the late 1800's? Lots of plans and examples in books and museums, plus an heirloom boat you can be proud of.
http://www.adirondack-guide-boat.com/agb_image_file/lewiscreek.jpg

Cuyahoga Chuck
03-18-2009, 09:52 AM
The one thing you are probably not going to build is an old fashioned nailed-stripper canoe. The construction of these stripper canoes is substantially different than the edge-nail technique that Farmer outlined for skiffs.
The canoe stripping technique that was outlined to me ( I hope I got this right) is extremely involved.
You need a heavily constructed mold similar to what is used for a wood-canvas hull. The ribs, which are quite small, are steam-bent and clamped to the mold. This technique needs a lot of closely spaced ribs. A 17 ft. stripper has approximately 80 ribs. The strips are layed on and clinch-nailed to the ribs.
The mind-boggling part is the shaping of the strips. Every strip is tapered toward both ends so that when placed shoulder to shoulder you get a hull that is fat in the middle and skinny on the ends. How they figure this out is beyond me. And, there is more. All the strips are interlocked with ship-lapping.
Even tho' this is an ingenious type of construction that can be both strong and light there is no cottage industry building nailed-stripper canoes and no how-to books for backyard builders. It's not hard to figure out why.

rmann
03-19-2009, 01:33 AM
Thanks for your advice and comments. To answer your question, my woodworking skills are not up to the traditional solid form construction technique which you describe (a nice description in 'The Canoe-A Living Tradition'), nor for that matter is my workshop.

I am a first time boat builder with some wood working experience. I don't want to attempt the impossible, and never finish the project, but just want to know if anyone is building strip boats without lots of epoxy and fibreglass, and what's involved.

Coincidentally my thoughts have also turned to lapstrake construction - but I thought of glued lapstrake. As you mention traditional lapstrake, how difficult is this process compared to glued?

JimConlin
03-19-2009, 07:44 AM
Thanks for your advice and comments. To answer your question, my woodworking skills are not up to the traditional solid form construction technique which you describe (a nice description in 'The Canoe-A Living Tradition'), nor for that matter is my workshop.

I am a first time boat builder with some wood working experience. I don't want to attempt the impossible, and never finish the project, but just want to know if anyone is building strip boats without lots of epoxy and fibreglass, and what's involved.

Coincidentally my thoughts have also turned to lapstrake construction - but I thought of glued lapstrake. As you mention traditional lapstrake, how difficult is this process compared to glued?

For each of the several construction methods you might consider, there are good books that describe the process well.

Starting at the bottom, taped seam plywood construction, see the books by Dynamite Payson, Jim Michalak or Sam Devlin.

For sheathed strip construction, see Ted Moores' Canoecraft.

For glued lapstrake construction, my favorites are the books of Iain Oughtred, John Brooks and Tom Hill.

None of the modern methods necessarily use large quantities of the reviled materials. A strip canoe might use 4 lbs. of glass and 6-7 lbs. of epoxy. The other methods would use less.

Traditional lapstrake construction, with steamed ribs and many rivets and other fiddly fastenings, requires a couple of additional skills, might take twice the hours and 25_50% more materials ($) than glued lapstrake.

Cuyahoga Chuck
03-19-2009, 09:14 AM
Thanks for your advice and comments. To answer your question, my woodworking skills are not up to the traditional solid form construction technique which you describe (a nice description in 'The Canoe-A Living Tradition'), nor for that matter is my workshop.

I am a first time boat builder with some wood working experience. I don't want to attempt the impossible, and never finish the project, but just want to know if anyone is building strip boats without lots of epoxy and fibreglass, and what's involved.

Coincidentally my thoughts have also turned to lapstrake construction - but I thought of glued lapstrake. As you mention traditional lapstrake, how difficult is this process compared to glued?

Succinctly, something has to hold the pieces together. The options for the catagories of boats you mention are metal fastenings and/or glue. There doesn't seem to be anything in between.
Metal fastened hulls usually require considerable interior structure like ribbing. Epoxy/glass reinforced hulls require sustantially less. The wood/glass/epoxy laminates like strip composites are very stiff and can be self supporting with no or very little interior reinforcements.
The same general situation applies to lapstrake. If the knuckles are clinch-nailed ribbing is required. But epoxy glued laps are much stiffer. A small hull ,like a canoe, needs no ribbing or other reinforcing if the laps are glued.
The downside is lapstrake only accomodates fairly rounded hulls. Common canoe shapes with tumblehome sides and flat bottoms are not practical.
If you survey the web you will find sites for stitch & glue construction, strip building and skin-on-frame construction. That is because these technologies are winners for home building. Lapstrake requires a steeper learning curve so it is practiced only by those willing to invest the time to learn how to do it. Tom Hill's "Ultralight Boatbuilding" is the bible for building small glued- lapstrake boats. Walter Simmons writes about building small nailed lap hulls.

Thorne
03-19-2009, 09:59 AM
If you don't want to try the uber-trad riveted lapestrake method (and I don't blame you), consider glued ply lapestrake without coating the entire hull in epoxy -- just using epoxy for the glued strakes and other attachments. Good paint and careful use can eliminate the need for using fiberglass and epoxy on the outside of the hull.

Lots of good books on the process as mentioned above, Oughtred's being a great one.

Todd Bradshaw
03-19-2009, 04:37 PM
Or....for those contrary types.....there is always cross-wise. Check out the before and after photos of this one. I don't know much at all about this old construction method, but wow!

http://forums.wcha.org/showthread.php?t=4332

rmann
03-19-2009, 05:54 PM
It would seem that glued lapstrake is a good alternative to strip building if one wants to minimise the use of epoxy and fibreglass.

Iain Oughtred's double paddle canoes are lovely boats, his Stickleback being the simpler of the three. I hope I have the skill for this, I certainly have the interest.

I am also interested in Harry Bryan's Fiddlehead canoe which can be built trad lapstrake or glued lapstrake. It is built dory style with minimal framing and a bottom plank instead of a keelson - a method also used in Joel White's Nutshell prams, Shellback and Pooduck skiffs, and Oughtred's Mouse and Granny prams.

I'm off to read Hill's and Oughtred's books - your comments have focussed me on glued lapstrake.

Cheers.