How to Repair a Fiberglass Crack
- 1). Widen the opening of the crack, using a rotary tool with a tungsten carbide cutter. This will allow you to determine the length and depth of the crack.
- 2). Apply fiberglass epoxy resin into the crack, using a plastic applicator. Fill the crack completely. Allow the epoxy to dry, following the manufacturer's recommendations.
- 3). Sand the area. Make a first pass with 240-grit sandpaper. Once the fiberglass is smooth to the touch, sand with 400-grit sandpaper.
- 4). Apply a gel coat enamel or sealer to the repaired area, following the manufacturer's application instructions. Use a similar color to the rest of the fiberglass.
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