Heat tolerance of Fiber Glass


New Hunter
I've never worked with fiberglass before, and have only the vaguest idea of how it's made and what not...so bear with me on an oddball question...

How hot can you get fiberglass before the item starts losing shape or, worse still, melting?


Active Hunter
well my helmet is fiberglass and I have left it for a few days in my truck in Vegas heat and I didnt have a problem. why are you concerned with heat, what are you planing on doing??????

secol FETT

Well-Known Hunter
fiberglass is not a plastic ... so the heat can't do any effect on it ... except ... if you shot with your flame thrower ;)


New Hunter
why are you concerned with heat, what are you planing on doing??????

Well, I love Star Wars as much as anyone here on Mercury, but honestly the costumes just don't seem to last... ;)

Actually, I'm thinking about using a metallic film instead of paint, and they're heat applied. I'll be experimenting with it on some plastic armor pieces soon, and if it works well, then I'll need a helmet to match.
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Well-Known Hunter
Actually fiberglass is a kind of plastic. Fiberglass is just that(glass fibers) but the resin and gelcoat are two-part chemical plastics. It can take much more heat than vacu-form plastics. I don't know how much is too much, but I've put my fiberglass gauntlets and helmet thru quite a bit to reshape parts with no problems.


Well-Known Hunter
Fiberglass can stand the heat .... up to 240 before it starts to loose it's form. The surface however, softens sooner.

Some people use fiberglass molds for vacuum forming. That gives you some idea of the heat resistance.