RE: EP airboat build
ive heard of a paint that is made to prevent rust, that will not harm foam, I havent used it personaly matter of fact i cant find it in the stores. i would suggest the foam hull also for your build. The only wood i use on my foam builds is where the engine will mount to the boat, usually a small square of 1/4 inch ply is all i use, then i cover the complete hull with 2 part epoxy ( can get it at any hardware store) paint it then use another thin layer to protect the paint. good luck with your build bro, keep us posted.