They aren't seen much today but I guess at one time simple home built skin & frame (canvas covered) kayaks must have been popular father & son projects. Lots of magazines like "Popular Mechanics" used to publish plans & articles for building them. My dad & I built one back in 1974 that I still have, and I now seem to attract the 'remains' of them. About 8 years ago I dragged one home from our local dump that someone thougth they'd try to 'fiberglass' (I think they stapled a bed sheet over the canvas & brushed some resin on top). It had then been left collecting mud, leaves & water for a long time. Needless to say it was pretty ripe inside. I stripped off the remains of the canvas & left it to dry & bake in the sun for a good long time. When I finally got to putting it back together I used an old abandon plywood road construction sign for some new frames (bright reflective orange on one side), and scrap stuff I had laying around for new ribbands. It was canvassed in the middle of our dining room on new years day a couple of years ago. Two coats of $5 a gallon oil base mistint paint & it's as good as new.