This probably won't help you but I'll be adding a thin ash coaming to my racing kayak. My plan is to cut an ~3/4" x 1/2" strip of ash, curfing a groove into it with a table saw so that I end up with a base of 1/2" and an overhanging lip of 1/4". This precut piece will then be heat-shaped to the curvature of the cockpit opening using a heat gun. Ash turns to rubber with heat from a heatgun. The heated ash will be clamped into place around the coaming so that as it cools it keeps it's shape. Once I have all the coaming I need I'll undo the clamps and mix up a lil' dookie to glue it into place. I'll add more dookie to do a thin fillet around the coaming for the increased holding power.

I want a thin wisp of a coaming because this boat is meant for racing only and will never be used for anything adventurous. The spray skirt will be used only for keeping water off my lap during marathon races so I don't need much of a coaming. I am hoping that a 1/4" lip will be enough to keep a tightly bound sprayskirt on while I push myself during competition.

For a kayak that will be used for normal use on rivers, lakes and oceans, I'd be building a coaming that was stronger, one with a 3/4" riser and a 1" lip all neatly filleted and fibreglassed into place. I just wanted to share my idea since this was an ash-coaming thread. Heck, maybe you can use some of the info I have presented.

Robert N Pruden