I am plannig on building a plane that has a foam core wing skinned in balsa sheet. I would really like to silk and dope it with a clear finish. The only worry I have is the Butyate dope and the foam. I am afraid that Butyate my seep through any seems I have in my balsa skinn and destroy the foam below. Any ideas on how to seal it? Can I use a few coats of thinned white glue on the seams to seal them off? The white glue would be sandable and not damage the surface of the basla like epoxy would. Or, is there another method of finishing I can use to obtain a natural look that is strong and fuel-proof?

Thanks

Just go over the seams with some DAP (vinyl spackling), let dry, sand smooth, then apply the silk or even silkspan, which would work just as well and cheaper, as all you want to do is to conceal the wood grain, then go about your business of brushing on the dope, it won't get into the wood, just apply a little bit on the first coat and let dry for 15 minutes or so, then you can apply as much as you want, you will be alright.

You could go over the surface with fiberglass cloth (very light cloth) and water based satin polyurethane (it should not attack the foam). After it has cured out then fuel proof it. When you cover the glass with several coats of poly-u the cloth will seem like it disappears. The same effect can be had with epoxy finishing resin.

Hogflyer

Excellent ideas. I think I may go over the skins with Polycrylic and silk and then top off with a couple coats of Poly U for fuel proofing. Let sit and cure for a week and go flying. Any more suggestions would be great.

Thanks