I decided to go for a molded fiberglass coaming. The plans for the Cape Ann came with appropriately-sized strips of mini cel foam. Glassing the deck went well, and I cut the opening to the size of my old templates. After trying a few things, I found some thin, junky plywood for the mold:
This was easier than it might look. I trimmed it down to the height of the foam pieces, and taped the foam down.
Next time, I may figure out a way to bevel the piece of foam & eliminate the gap caused by the curvy parts of the deck. It seemed like a big gap to be bridged only by tape.
I covered the whole thing with shrink wrap.
The layers of fiberglass. I started with 6 oz. glass-the bias-cutting thing really does help it work around curves. After four layers of 6 oz, and two of 4 oz, I thought I had built it up quite a bit.
After much scraping, grinding, fill coating, and sanding, I trimmed the edge, and tested the fit of my spray skirt. It fit just fine, and the whole thing released pretty easily from the shrink wrap. I gave it a coat of epoxy primer, and several coats of black paint. It was easy to bond it to the deck with dookie.
After some laborious trimming & sanding, I decided that it looked too "sinister" or something, and repainted it my favorite Jolly Green:
As I mentioned above, I thought I had built up quite a bit of thickness, but this came out to about 1/16". It seems strong enough.
The side & knee braces went routinely & well.