How to Fix Scratches on a Gel Coat
- 1). Obtain a color sample card from a paint supply store and locate a color on the card that matches the color of your gel coat as viewed in natural light. Return to the paint supply store and ask those responsible for mixing the paints what colors and ratios are necessary to reproduce the color of your gel coat. Purchase a gel coat repair kit containing gel coat paste, hardener and pigments matching the colors you need.
- 2). Clean the surface of the gel coat with a damp cloth to remove any dirt that could interfere with the repair. Take a screwdriver and draw it down the length of the scratch to widen it into a "V" shape. This shape is needed to allow the gel coat repair paste to completely fill the scratch, creating a new solid surface. Wipe any residue created from scratching the gel coat away with the damp cloth, then pat the surface dry with a dry cloth.
- 3). Place an ounce of gel coat paste into a cup for color matching. Add tints from the repair kit to the cup, matching the color formula provided at the paint shop as closely as possible. Mix the tints into the paste using the stir sticks included in the kit. Keep careful track of the colors added adjusting the colors as needed until you reach a match. Test the mix onto the gel coat by placing a drop onto the surface. Make further adjustments if needed, then write down the final formula for the mixture in case you need to mix a further batch.
- 4). Add the hardener from the kit to the paste to catalyze the gel coat for use. Follow the instructions provided by the kit manufacturer on the amount of hardener needed. Stir the mix thoroughly.
- 5). Wipe the scratch with a cloth dipped in styrene to reactivate the gel coat for a better chemical bonding with the new paste. Immediately fill the scratch with the paste using a plastic spreader. Slightly overfill the scratch to allow for shrinkage of the paste as it hardens.
- 6). Cover the patched area with plastic film, taping it into place with masking tape. Allow the paste to cure for 24 hours, then remove the plastic to finish the repair surface.
- 7). Attach a 150-grit sheet of sandpaper to a sanding block. Sand the gel coat with the edge of the block to level out the patch with the rest of the gel coat surface. Switch to 220-grit wet/dry sandpaper. Saturate the sandpaper and then use the flat of the sanding block to feather the patch with the surrounding surface, blending the new paste in with the old gel coat until it's level to the touch. Keep the surface wet with water while feathering the patch.
- 8). Switch to 400-grit wet/dry sandpaper without the sanding block and sand the area until it's visibly blended with the surrounding gel coat. Change to 600-grit wet/dry and go over the area a second time, smoothing out the area and removing any scratches made from the coarser pieces of sandpaper.
- 9). Pat the surface dry with the dry piece of cloth. Apply rubbing compound to the area with a piece of soft cloth. Buff the compound using small circles to create a glossy shine.
- 10
Wax the entire surface after polishing it to protect the newly patched area and further blend in the repair.
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