I don't like using plywood because it explodes if it gets wet inside. Yeah, I know, just encapsulate it in epoxy etc., etc., etc. But as long as the potential exists and so does regular wood, I'll go regular wood thankyouverymuch. Mahogany works well, ash, just about any old boat builder's wood. Here I've used basswood -- and I've been having nothing but the most excellent luck with basswood since I started using it several years ago.

The fit doesn't have to be precise, just close enough to set in place without using *too much* thickened epoxy, sorta works like a brick in mortar.

There shouldn't be much warping tendency if you use similar glass lay-up on the inside and outside of a reasonably well stripped structure. The hookie thingies may reinforce good work, but I wouldn't expect 'em to correct iffy propositions.

: I'm curious what you're using as the brace/stiffener/hook for the
: underside of the hatch covers. I've used plywood - it shouldn't
: warp - but it's not too attractive. Kurt looks like he used a
: solid wood and carved it; any warpage with that? What wood would
: you suggest that would be that stable? And getting the shape
: 'just so' has been a headache - following the nearest forms only
: gets you so close. I've 'filled the gap' using saturated fg
: cloth, but a bit less elegant, maybe, than what is possible.