RE: weight for sure start plane
I had not considered sealing the foam with glue, I can see where that would work. As a result almost all paints that were fuel proof would work. I will give it a try on my next foam core project.
The reason for latex is because it won't hurt the foam and the polyurethane seals the latex, However I have found that most latex paints are fuel proof if allowed to completely dry.
Thanks