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What does BONDO short strand fiberglass body filler NOT stick to? Answered

I'm thinking of building a small canoe by making a cheap mold and spreading the fiberglass stuff on it and popping it out. However, it is sticky. Anyone know what the stuff DOES NOT stick to. And perhaps and ideas on making a mold.


Wax, PVA, polypropylene

isn't there a release agent for fiberglas/bondo? something you spray or brush onto molds?

ah...dint know. I've seen, used sprays for other molds (release for electronics potting compound molds, but I never really questioned what they were...)

You can spray PVA , poly vinal alcohol, It is expensive and vary flamable. I have used saran wrap from the grocery store ,cheep and easy. It will stick to body from static and will peel off after base is molded to your car ,then foam can be used to build flairs or wide body kits.


8 years ago

I used to work in a fiberglass shop and we used mylar to keep the resin and mat's from sticking. It's that shiny plastic thin film stuff, perhaps you could staple it on the form? We also used wax as a mold release.

I dont like film cause i hate how flimsy it is, making it hard to work with.

does candlewax work. will bondo stick to coroplast?

I never tried candlewax... We used to just use cheap paste wax. Though I cant remember the name, it came in round tubs like margarine containers. Another cool thing we used to use for building boxes and covers out of sheet fiberglass material was a plain old glue gun, then reinforce the joints with mats and resin. Could actually build some pretty cool stuff like that.

Stew2: that's a saavy idea. I use plastic wrap when I'm gluing wood and don't want my spacers or clamps accidentally getting glued to the item by over spill, although I';d never have thought of using it for that (even though now that i think about it, commercial foam insulation is always sandwiched in plastic sheet, and printers, monitors etc often come packed that way.

Nothing sticks to rabbit fur either....