Model Forum / Radio Controlled / Water Models / April 2007

I recently built an electric foam/balsa catamaran myself.  I
made 2 foam hulls joined by a balsa deck.  I left the foam
uncovered and finished the whole thing with water-based
polyurethane.  If I had it to do over, I would have used
resin and fiberglass cloth.  Without it, the foam dents and
mars easily.  If you  skin over all surfaces of the foam
with balsa, then the dent resistance of the resin and glass
cloth might not be needed.  I would still use the water
based polyurethane, however.  Even if you use a foam sealant
coating followed by any finish that can "eat" the foam, even
the tiniest crack will allow it to penetrate and destroy the
foam.

"speedsport"