I agree with Jay. Sanding sealer is a filled lacquer. Lacquer is that stuff that goes white when you put your beer on the coffee table without a coaster. Its not water friendly. It will compromise the wood/epoxy bond and you'll have just wasted your time and money. They don't call it the wood epoxy saturation technique for nothing. If you have to economize use polyester resin or luan. The boat may not last as long, but then you get to build another!