need help with styrofoam and bondo!


Well-Known Member
Hey everybody,

I'm currently working on a Clone Wars Plo Koon costume. I started with the forearm armor since I already had the styrofoam to sculpt into a vacuumform mold. I spent two days sculpting the forearm to my specifications and then applied bondo to create a surface I could sand.

Here is where the problem began. When I applied the bondo the styrofoam began to melt! This totally ruined my sculpt:cry. Now I have to resculpt a new forearm and coat it on something to prevent the bondo from doing it again.

Are there any solutions to this? I've heard of Rondo and Gorilla glue as a protective coating, are these any good? Any information is appreciated.

Thanks for reading
May the force be with you all,


Sr Member
You could also coat it with urethane resin (smooth cast 300 or such) and fill over that. But clonesix is right you need a way strong buck to do vac forming with.

Mostly Fantasy

Well-Known Member
I've used a coating of masking tape (completely cover the surface of the EPS foam with tape), over which I've actually used fiberglas resin and cloth, with no problem. Urethane foam will solve the problem as previously mentioned, but it's more expensive.


Master Member
Can anybody link to a good place to buy some urethane foam? Preferably the firmest kind available. I have a project that requires a couple square feet of it.
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