: I'm currently attempting to build a skin-on-frame kayak, as my first boat.
: The frame is 1/2' PVC pipe, made so I can disassemble it into many pieces
: for transportation. I'm contemplating different types of material for the
: skin, and this leaves me with a bit of a question. The forerunners so far
: are Marine Vinyl and Canvas. I know Marine Vinyl is waterproof, and canvas
: is not so it would have to be treated somehow (I don't know how). Is
: sewing required of whatever material I use, or can someone suggest a
: better way than going to an upholsterer? Anything someone could tell me
: about kayak skins would be helpful.

1/2 inch PVC is probably going to be too flexible, unless you use a lot of it, and have fairly closely spaced frames to support it. Even 3/4 inch can be a problem. You might want to consider using 1 inch and bracing it by connecting it with short sheets of plywood to create girders.

Check the archives for anything posted recently by Tom Yost and you'll see that he has gone whole-heartedly into the camp of the PVC skin. It is a vinyl material (PVC) which is a little heavier than the marine vinyl you are probably looking at, and a lot stronger. He trims it to size and uses a contact cement to create permanent, watertight seams without sewing. The amrine vinyl sold at fabri stores is great stuff for upholstery (I just recovered a motorscooter seat with some) but the reinforcing base fabric seems more designed for flexibility than for strength.

Tom really likes using aluminum tubes and high density polyethylene plastic for the frames. No painting or sanding needed and the parts just snap together. He has offsets available, too. Last I heard they were free. From these you can create your own plans by graphing the coordinate points and connecting the dots.

The cost of the PVC skin is fairly close to that of good canvas, and it does not need to be coated with any type of paint or other waterproofing compound, so you avoid that cost.

Another option is polyester fabric covered with several coats of a urethane varnish. George Dyson Baidarka in Bellingham, Washington, sells some very heavy, and very strong, fabric at reasonable prices.

Good luck with your project. Send along a picture or two to the bulletin board as you go. We love watching others build.

PGJ