It sounds like you are doing something similar to this:

http://www.capefalconkayak.com/adirondackguideboat.html

or this:

http://capefalconkayak.com/jwboat.html

I don't believe that the skin is affixed to the frame anywhere but along the gunwales and possibly on the stem boards. With synthetic fabric (especially the lighter weight stuff) the coating will typically soak through and 'glue' itself to the frame anyway. Fixing the skin to the bottom/keel during skinning would only make things more difficult, but after skinning it shouldn't be detrimental. It just seems redundant to do so when the skin will become glued to the frame anyway.

: I'm starting to plan my winter build: an SOF adaptation of LF Herreshoff's
: 18ft sail/rowing "Carpenter" design (the popular Sea Pearl 21
: sailboat was adapted from this design). The original design has a flat
: bottom which is about half the width of the beam at midship and tapers to
: within a few feet of the bow and stern.

: I would like to use marine plywood for the bottom with steam bent white oak
: ribs and 1050 denier ballistic nylon for the topsides. The bottom will
: also need a slot opening for the centerboard.

: I need help on how to skin this baby. I'm assuming its best to use a single
: piece of skin from gunwale to gunwale. Do I want to adhere the skin to the
: bottom or let it "float" or "slide"? If yes to adhere,
: then with what? Epoxy? One of the many types of marine caulks? Something
: else?

: Any help or redirects would be appreciated.