How to Use Fiberglass Resin for Body Repair
- 1). Grind the damage smooth, using an air grinder. Grind away any loose or damaged material and gradually taper any edges on the damage. Wear a respirator and safety glasses.
- 2). Clean the area with a rag and acetone. Remove dirt or grease from the surface.
- 3). Cut the fiberglass mat with a razor knife, making the first layer the same size as the repair. Cut each following layer 1/4 inch bigger than the last. Use as many layers of mat as it takes to restore the damage to its original thickness.
- 4). Pour the fiberglass resin into a small bucket and add the catalyst, following the specifications on the containers. Stir the resin thoroughly with a stir stick. When the resin is mixed, you have around 20 to 30 minutes until it will harden.
- 5). Wet the surface of the damage with the resin mixture, using a 4-inch felt roller. Apply the smallest layer of mat directly in the center of the damage and saturate it with resin. Evenly roll the resin onto the mat using the felt roller. Remove any air bubbles that will be trapped under the mat using an air roller. Apply the remaining layers of mat to the repair, following the same process for each layer. Let the fiberglass harden.
- 6). Sand the repair smooth using a palm sander with 200-grit sandpaper. Wear the respirator. Sand the repair until the edges blend in with the existing material and the repair is level with the surrounding surface.
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