Create a mold using a 5-mil Mylar sheet backed by Styrofoam to keep it flat. Polyester resin does not adhere to Mylar, but you may also use polyethylene or polypropylene, ensuring they are well-waxed for a proper release. This guide provides a step-by-step demonstration of a simple fiberglass repair. The methods outlined here apply to various fiberglass products, including jet skis, shower stalls, car and truck bodies, boats, canoes, and kayaks. Before you start any repair project, it's essential to gather all the necessary materials and tools. Here's a list of what you'll need: Safety. One key thing for high stress/flex is to use 2 layers of fiberglass: one piece that overlaps the damage by 1-2 inches, and a second piece that overlaps the first by 2-3 inches.
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