I created a fiberglass mold of the top of a board last year, and I'm finally getting around to testing a section tonight!
The mold's surface is gelcoat, so I need to apply a release to it so that the cured epoxy won't stick to the surface and ruin the mold. A fresh mold needs a bazillion coats of wax to release.
I use Fiberglass Supplies 306 B sealer/release wax.
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