Resin will eat the styrofoam panels you mention in your post. You can get
urethane foam in whatever thickness that will serve your purpose and is
compatible with epoxy, or polyester resin, and probably vinyl.
MAC
"Tom Best" wrote in message
om...
I'd like to build a 4x10 fiberglass on foam core panel. Medium to
light duty cover for a center well. I plan to sit/row on top of it
and use it as a roof for a canvas cabin. Can I use the blue or pink
closed cell foam from home depot or do I need special foam.

I realize I can order end grain balsa or specialty foam but the home
depot stuff would be a lot more convenient and I'd like to keep this
experiment cheap. Will the expoxy/glass stick and will it have the
properties neccessary to function in this capacity?

Thanks in advance.

Tom