boat from one or two sheets of plywood

I was on a boat building forum about a year ago and there was a guy wanting advice on a canoe/kayak he was designing that he planned to build from one sheet of plywood, or maybe two sheets, but no joints, limiting the maximum length to eight feet. Might be an intersting design/build challenge. I think I could build a pretty decent little river dory from two sheets. I think I could build a canoe from one sheet. A punt would be an obvious choice. Might be interesting to see what people would come up with.

 

Hannu's boatyard has a slew of designs for one, one and a half, and two sheet boats. Probably not a bad place to start.

 

Here are my contibutions:

A single-sheeter kayak:

http://www.boatdesign.net/forums/wooden-boat-building-restoration/last-one-sheeters-37550.html

And a two-sheet kayak:

http://www.boatdesign.net/forums/wo...ration/mysticshore-12-gets-started-39315.html

 

Here is the boat I built from two sheets and some misc solid wood.



http://newboatbuilders.com/pages/Dinghy.html

 

they got 10' marine and regular plywood.

Little more per sqr ft, but worth it, IMO.

8ft just too limiting.

 

I've always thought of these as joke boats. Reasonable plate layout on an 8' panel, is fairly easy and limiting yourself to no longitudinal joints, yet having several athwart and centerline joints seems self defeating. 8' boats suck at everything except as garden planters, which is all they're really good for, unless you need a dinghy for a mother ship. 8' boats can barely hold a single crew member, let alone a rig, stores, outboard, etc. There are thousands of designs for small craft, some using very few sheets of plywood. Everyone I've ever met with an 8' boat wished for a 10' boat, again unless deck storage forced their hand at the 8'.

 

these WalkerBay 8ft are OK for fishing, etc for those who

just aren't gonna use a kayak, canoe, or inflatable and want to haul it in back of truck.

But as they are full 8' stem to stern with a big curve I think they are quite a bit bigger than a "one sheet boat", with better shape overall. I'd guess they are 30% bigger than One Sheet Boat.

http://www.walkerbay.com/sites/default/files/WB8-Specifications-Expanded_1.pdf

 

I wouldn't want a one sheet boat. Par's right that that is way too small, but the dinghy I built holds two just fine (I've taken it sailing with me and my wife) and it sails well considering the tiny sail. It could actually use twice the sail area. It all depends on what you want, and the old joke is that every boat owner wants a bigger boat. But for someone starting out learning to build boats a two sheet boat is a great project.

 

Some interesting designs. LP's layout for the last of the one sheets is pretty ingenious and a pretty impressive design for a single sheet. To some degree I tend to agree with PAR, even if he does put it a bit bluntly. But as Squidly pointed out, and the one thing that would inspire me to build a boat that short, a boat that will fit in the back of my pickup would be handy. Pulling a trailer is a pain in the neck, and putting a boat up on top of a 4x4 truck is a pain in the back. Squidly is also right about the ten foot sheets. I have a source for ten foot sheets of marine plywood. Hyde sells a little drift boat that fits in the back of a truck, and could possibly be duplicated with two ten foot sheets (can't remember the exact length). There are also a couple other companies that make little fishing skiffs that could be made from two ten foot sheets. Eight foot sheets might be pushing the limits of practicality, but ten foot sheets could make a reasonable boat.

 

For what it's worth, LP's one-sheeter fits in the cargo bay of the biz-jet his company owns.

 

And what would be the defining purpose for a one sheet boat? It is true that enterprising souls like us sometimes make things just because we can. Bolger actually had plans for a boat he called Shoebox. It is 66 inches long and 39 inches wide. It needs two sheets because it has side tanks to make it practically unsinkable. It is so damned ugly and impractical that no one would want to steal it. That is its' only virtue.

A one sheet boat is possible but not very practical. A one sheet double ender could be about 93 inches long by 24 inches wide with 11 and 7/8 inch sides. It would displace about 210 pounds at 5 inch draft. Alternatively we could build a box ended scow at about 24 inches wide by 84 inches long. That one would support a lot more weight at 5 inches draft ....maybe 350 pounds. It would make a decent box for winter tomatoes but not a very good boat.

You can make a fairly adequate little boat with two sheets. Three sheets would give you a lot more latitude to build a really good little boat.The three sheeter could have a much diminished propensity for drowning its users too.

 

Because you can is a perfectly valid reason to build a boat, especially one that only requires one sheet of plywood.

 

A much better boat is to go with 4 sheets plywood for sides and bottom and some treated 2x6's for the stern, seats, and ribs. It is still minimalist and cheap, especially if you go on craigslist and barter for materials, and you have a boat you could stick a 25-50 horse outboard on. 16L x 4w x 2h. Some HDPE plastic makes a great keel or bottom protectors if you use your imagination (I used a triangular pc in the center and flat pieces for the rest when I built my plywood boat).

the great thing about a boat like this is that is cheap and worry free and easy to bail and easy to add on to.

 

copying my message from an another thread:

These might give ideas
http://flo-mo.weebly.com/one-sheet-boats.html

There is a good picture set of building his boats too. Also the tortured plywood kayak is a clever way of building thin hulls.

His user profile on wooden boat, check the build threads

http://forum.woodenboat.com/member.php?24392-flo-mo