Hey Leighton,
If you use blue Styrofoam you can carve a cowl without the frame structure. I have put glass cloth with West Systems epoxy on them to use use as plugs to make a cowl mold, or, you can hollow out the inside to clear engine/pipe, then glass the inside and use it as a one off cowl with built in flotation.
Just a suggestion. CHEERS !!! Bob
thats cool and all but what i was going for was to make sure that the cowl was symetrical. I've done the blue foam and what i find is that if you don't create some kind of fixuture to constantly check the outter shape one side could be bigger that the other...sometimes if your eyes are really sharp that won't happen but it happens to the best at times. the cowl came out great.... even the guys in my club like this one better than the last one.
What you could also do is sandwich in some vertical ply formers between foam plys and add a lengthwise keel(for lack of a better term) and it will help keep everything straight as you shape the foam as well as point out where something isn't right. If you're doing a plug, glue all the framing together and, additionally, you could add some side stringers for additional ridgidity. If this is a one off, you remove as much foam as you can and leave part of the cross frames for strength after the cowl is finished on the outside
