Correct, I do not epoxy my frames, nor do I use marine plywood. I just use plain old exterior grade plywood, and have not had any problems.

My skin of choice is nylon, coated with PU. We did a test at SSTIKS (a raffle to see who could damage the skin with just their body) a few years back and nylon with PU is very tough. We had a quite large man jump off of a picnic table onto the skin as it was held in the frame, and there was no damage, except mayby to his ankle. Stabbing it with a ball point pen broke the pen, and did not puncture the skin. Even the claw side of a hammer had a tough time damaging the skin. A knife was the thing that could do the most damage, be even that has do be deliberate.

Having said that my current two builds are using canvas paiter's tarps coated with exterior latex paint. They are kids kayaks, and will see rough use, but only need to last a few years. I'm doing them on the cheap.

: From what I've read, untreated canvas isn't all that easy to find
: anymore, and not all that much less expensive. Probably the
: easiest, and cheapest skin is nylon from either Dyson or
: skinboats.org, coated with Zar varnish. You'll also want to do
: lots of searches at qajaqusa.org's forums. Not that there aren't
: good posts here about skin on frame boats, but qUSA is where
: most of us nutty SOF aficionados hang out.

: You could save @ $100 US on a plywood frame and stringer project
: like this if you omit Tom Yost's epoxy glued construction, and
: just last the stringers to the frames. Mike Hanks out in Tacoma
: doesn't even bother epoxying his plywood frames. If you have a
: good skin and coating, and you don't capsize, there won't be
: enough water in the boat to make marine plywood go bad anyway.

: Right now, Tom's designs are probably some of the nicest to do in a
: plywood frame and stringer construction. I build a Sea Rider,
: and I love it. But that's a different boat from what you
: originally posted, and I am not a fan of bathtub kayaks, having
: sold countless plastic 10' rec boats.

: Brian