How to Repair Island Packet Gelcoat
- 1). Surround the gelcoat damage with masking tape. Tape one strip of tape 2 inches away from the damage. On the inside of that tape, apply another strip 1/4 inch away from the damage. The outer tape stays in place during the entire repair. You replace the inner tape when it wears out from sanding.
- 2). Sand the damaged gelcoat down until you reach the fiberglass. Don't sand into the fiberglass; if you do, then you'll need to repair the damaged glass. You can use power tools, such as a random orbital sander, to speed up the process, but beware power tools increase the risk of sanding into the fiberglass. If any cracks lead away from the main damage, sand that area down to the glass, too.
- 3). Wipe down the damaged area with acetone and replace any damaged masking tape.
- 4). Mix 1/4 cup of gelcoat with surface curing agent as directed in the gelcoat instructions. Once you mix the gelcoat you have about 10 minutes of working time before it starts to harden, so work quickly.
- 5). Paint on a thick layer of gelcoat. You want to paint on enough to come level with the original surface. Alternatively, you can paint on several layers of gelcoat by waiting for the underlying layer to dry. On vertical surfaces, you may need to use several coats, because a thicker coat will drip and run. When the gelcoat starts to set, feather the edge into the old gelcoat using a plastic paint spreader. Remove the inner tape.
- 6). Add a new inner tape layer when the gelcoat is dry. Sand the gelcoat smooth and fair it into the hull. Start with 80-grit sandpaper, then work progressively from 120-grit to 300-grit. Switch to wet sandpaper from 400- to 600-grit. Wet sandpaper gums up quickly, so keep it wet and wash the dust out often by dipping it in water.
- 7). Buff the finial finish using a random orbital sander and a foam compounding disk. Fill the disk with a microfinishing compound and buff until the gelcoat shines like the undamaged surface.
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