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[aspiekid0101]

Alright, I'm planning to use fibreglass with my current cosplay project, but as this will be my first time using it, I need to know a couple of things from anyone else who's used it in the past.

Can fibreglass be used on cardboard, or does it (the card) have to be sealed with something first before I apply it? Also, I was told that fibreglass can't be spray painted without being sanded. Is this true or not?

Thanks!

[Zil]

There are a ton of threads on this forum about fiberglass work. You should search the forum and dig up a few to look at. You can also google "beginners guide to fiberglass" or something similar and I'm sure you'll find helpful sites.

Cardboard is non reactive, so the cloth and resin can be directly applied to it. Carboard can warp however, so it's not the best base for all projects. If you use fiberglass cloth with the resin, the cloth texture will show through. To get rid of that, you need to apply a sandable material. You can apply multiple coats of resin over top and sand that, but I've heard the dust is toxic and very hard to do by hand. People commonly use Bondo or paperclay for this instead. Spray paint should not react with fully cured fiberglass resin, people only sand it to get rid of the texture.

[catfetus]

What I do with cardboard if I'm going to put resin on it is paint on a thin layer of resin first (to avoid warping, as Zil mentioned), let that layer harden, and then proceed with adding more resin and your fiberglass.

Make sure you have a respirator with filters if you're going to be working with resin! It's very fumey.

[verdatum]

The dust from bondo is every bit as harmful as the dust from resin. And the dust from sanding paperclay is not good for you either. It's not a big deal though. Use a dust mask. Work outside if possible. And if not working outside, hold a vacuum cleaner hose right up close to the area you are sanding; ideally one with a HEPA filter on it.

And avoid using polyester resin indoors. That smell hangs around for weeks.

[RoninEclipse2G]

Originally Posted by Zil

Spray paint should not react with fully cured fiberglass resin, people only sand it to get rid of the texture.

Not exactly. Cured resin tends to be too "smooth" for paint to stick to properly, and can even have a waxy residue that will cause the paint to fisheye really badly. You sand it to scrub off the waxy residue and give the surface texture for the paint to bond to.