I am building a Vaclav style coaming for the first time on my RBA and thought I would share a picture and some learnings.

Vaclav's technique starts with a bendable plywood riser that is glued to the opening and is the basis of a form for a carbon fiber coaming. I was looking for a way to hold the 1/8" plywood while fileting the joint.
I took a strip of formica, glued two blocks to its rough side and used a spreader clamp to the force the plywood tight against the edge of the opening with the formica. It gives you even preasure all the way around and works better than Vaclav's multiple spreader sticks.

The inner ring of masking tape lets me make a clean filet and is removed prior to glassing. The outer ring of masking tape helps with a clean transition glass edge. The first coaming I made 5 years ago was a mess that required major clean up. This one required 5 min with a cabinet scraper to clean.

Regards

Jack