: I am considering taking a poncho for rain gear and also using it for a skirt
: I am going to try to build the combing and lip using auto-body two part
: plastic and wiping it up in a straight line

John,
You're such an old fashioned kind'a guy. Everything old is new again!http://albums.photopoint.com/j/View?u=1502758&a=11341576&p=41172012
The pic is from Adney and Chappelle's skin boat book. The tooy-leek is secured at the face, wrists and coaming for "dry" rolls. So I would guess it doesn't leek tooy-much.

As for the coaming if you can get your hands on the Nov. 2000 "EpoxyWorks" (Gougeon Bros. No. 16) there's a detailed article on built up coamings using a kevlar braid tube and a hose mold, ala Dave Hazan. The dynel braid discussed in the recent hollow paddle thread might work here as well. Then there's always modeling clay like the auto makers use for 3-D mock ups. Good Luck.
Geo. C.