There is a book by Wolfgang Brink, about building badarkas, that has a pretty
good description of how you sew the skin on the boat. The title escapes me,
but with a name like his the book shouldn't be hard to find. There are lots of
other books out about building skin on frame boats.
You don't use a waterproof fabric. You sew fabric on and then cover it
with a waterproof coating such as Neoprene.
Fabrics can be stretched to some degree and some fabric can be shrunk with
heat. Concave shape may not be possible.
you might check out guillemot kayaks at this address:
http://www.guillemot-kayaks.com/Building/Building.html


What I
want to do is fabricate a skin for a very non-standard hull shape from
a waterproof fabric such as folboat uses. So what is that type of
material called and where do you order it? And then how do you go
about forming it to the hull shape? I assume stretching to shape is
not the answer. Is it a matter of cutting, stitching, and
seam-sealing? I don't have a copy of Ralph Diaz' book....is there
anything in there on making your own fabric hull? Replies from
folks with first hand experience in this sort of fabrication will be
much appreciated.