Anybody ever use coosa board to build a engine hatch . Was it strong enough to walk on and how hard was it to work with . Thanks

i do it all the time, done dozens. Plenty strong but you will need to encapsulate it. I did one not to long ago for a redline that is six feet long and thirty inches wide, i can set it long wise on saw horses and stand on it no prob and i am 210, only flex's an inch or so. Supported all around you wont have any prob. This one was .700" with two layers of 1708 on each side and bagged down.

Dave, Do you just butt the ends of the board and rely on the glass skins for the tension and compression forces?

if I have to build anything bigger then a four by eight I will bag up something on a layout table, you can custom order five by tens as well. I suppose in theory you could just butt them together and rely on the surface laminates, I mean most boats are built entirely grid scored coring with literally thousands of butt joints anyways plus anything with that big a span is going to require some sort of stiffening ribs or something that can be strategically placed.

I've used Penske board (similar to Coosa) for my engine hatch-I can stand on it and I'm 250. I cut a few slices (not all the way thru) to get the curvature I needed and put 1 layer of 1708 on each side. I also glassed two stingers to the underside.