: I followed the info he got & it is really interesting.
: I guess it is possible to build any sof as foldable without any special
: plans.

: I couldn't find an image/webpage/text explaining how the joints are made.

: does anybody know where such info exist ?

The plans for the folding kayak from clark craft contain just one of several methods for joining the parts.

Basically, it depends on how small you want things to "fold", as some so-called "folding" kayaks really just disassemble into small parts. Hinges, or parts that would work like hinges and allow the materials to actually fold are sometimes not needed. some part are held together with clips, or slide into slots. Some use clevis pins and others use snaps, or wingnuts.

Actually, it doesn't take a lot of design work to make the connectors, as the whole thing is really held together by the skin. Klepper makes the skin in the form of an envelope -- you drop the front and back halves of the frame into the long cockpit opening and join them together, in a manner that stretches the skin tight. The Clark Craft kayak is similar. when adapting other plans to making a collapsible kayak, though, it is common to assemble a full hull, and then lace on the skin, drawing the laces tight much as you would tie shoe laces. You would lace up bow or stern decks, or both. The idea would be the same as sewing on a kayak skin, but instead of using a needle and heavy thread you would use thin rope passed through grommets in the skin. The fabric would be folded first in such a way as to keep out water, of course.

I'm considering a frame made from conventional 1 inch PVC plumbing pipe and off-the shelf connectors. An occasional "T" connector placed in the chines would allow a cross memeber for stiffness, roughly the equivalent of a thwart on a canoe. Frames would be make of plywood. I'd draw the frame design on the wood, drill out the corners of each frame, where the pipe would go, with a 1 1/4 inch drill bit, or get one as close to the actual outside diameter of the PVC pipe, and then cut out the rest of the fram with a sabre saw. those big holes in the corners would make it easy to reorient the saw for cuting each side, and if I did it right, they would expose about 25 percent of the pipe, and wrap around the remaining 75 %. So, the skin would rub on the smooth plastic pipe instead of the rougher wood.

I'd be happy to draw a picture of this once I get my home computer and scanner back up and running, but perhaps you get the idea without the picture.

Hope this helps.

PGJ