How to Repair a Crack in Fiberglass

Fiberglass repair is an art that can be tackled by anyone willing to employ a little patience and concentration on the project. Whether dealing with a shower, tub or boat, repairing fiberglass cracks can be tedious but are worth the effort. Below are several options for repairing cracks on fiberglass surfaces.

Difficulty: Moderate

Instructions

Things You'll Need:

• Fiberglass epoxy resin
• Plastic resin applicator
• Rotary tool
• 240 sandpaper
• 400 sandpaper
• Gel coat enamel

1. Determine the actual size of the fiberglass crack. Oftentimes, the crack is longer and deeper than what the eye can see.

2. Take a Dremel or other rotary tool with a tungsten carbide cutter that is not much larger than the crack itself and widen the opening slightly to determine the length and depth of the crack. Hold the tool at a 45-degree angle and make a small valley along the crack.

3. Work a fair amount of fiberglass epoxy resin into the crack with the plastic applicator. Ensure that the crack is completely filled to the edges with resin.

4. Let the fiberglass resin epoxy dry according to the manufacturer's directions.

5. Sand the area with a quality 240 wet/dry sandpaper until hand smooth. Once this process is complete, sand over with wet #400 sandpaper.

6. Apply an similarly-colored gel coat enamel or sealer to the repaired fiberglass crack area.

Tips & Warnings

• Work in a well-ventilated area when dealing with epoxy and resins.
• Press enough resin into the fiberglass crack to fill the void and allow a small overage to allow for sanding.
• Always wear protective eyewear and a facemask when applying resins and epoxies.
• Use caution when working with rotary tools. Wear short sleeves and maintain control over the device.

Resources

• Find great tips for fiberglass crack repair
• See a great fiberglass crack repair tutorial here