I have recently shaped and glassed a foam core skimboard… i used epoxy laminating and hardener for the top with two layers of 4oz warp, for the bottom i switched resins, which i bought some Suncure 249 surfboard resin to add 2 layers of 6oz to the bottom… has anyone used the suncure resin? bought it to be cost effective to save resin and to use on future boards… Here are some pictures of what ive got so far… thank you.
If you already lammed one side with epoxy, and you’re going to try to lam the other side with resin…
YOU’RE GONNA HAVE A BAD TIME
Suncure 249 is a polyester resin… You already started with epoxy, so finish with epoxy. Even if you make the best mechanical bond ever, there will be no chemical bond between epoxy and resin. While this is “okay” to do with something like a hotcoat or gloss coat (I say “okay” very relatively in this situation), it is a fools errand to do it in the lam. You’ll end up with your laps not making a bond to the glass underneath them, and basically a board held together by nothing more than a hotcoat. With the ammount of abuse a skimboard takes, I would give it a few days at most before the laps break and the board splits open like a cheap costco pop-out
If you really want to sun-cure your board, you can either go spend the buku bucks on a bottle of epoxy UV catalyst (nobody really stocks this, so you’d have to get it directly from Wahoo international), or to buy a bottle of this stuff at your local fiberglass supply depot
The important thing to remember here is this: while epoxy will bond to polyester, polyester will not bond to epoxy.
Also, out of curiosity… what kind of foam were you using that prompted you to use epoxy in the first place? If it’s any kind of EPS or polystyrene than you run into the whole other problem of polyster resin being incompatible with those kinds of foam… Ever see the alien movies where the acidic alien blood eats through multiple steel floors on the spaceship? Yeah, it’s kinda like that
If the foam is pink (Owens-Corning) or blue (Dow), it’s XPS. If it’s fused white beads, it’s EPS. All three are styrene and will be melted by polyester resin.
Ideally you’d want to use a more dense core foam like divinicell for something like a skim board. You can use any foam, I’ve seen it over the years, but the board will have a shorter life span. Good advice coming from everyone!