How to Gelcoat a Canoe
- 1). Turn your canoe upside down and set it on sawhorses. Wash the boat thoroughly and let it dry. If the hull needs repaired, take care of that before you go any further. When the hull is ready, clean it again with acetone and a soft cloth to remove any grease or oil, loose dirt or wax.
- 2). Sand the hull with the orbital sander. Start with 150-grit sandpaper and then follow up with 200-grit, then 400-grit wet/dry sandpaper. Don't sand so hard that you thin the hull. Just go over it lightly to smooth the surface and give the new gelcoat something to adhere to. Clean the hull again with acetone to remove fiberglass dust.
- 3). Wait until you have eight hours to devote to the rest of the project since the gelcoat requires application of at least three coats, four hours apart. Just before you start the gelcoat, wipe down the hull with styrene to activate the old gelcoat and to improve adherence of the new gelcoat.
- 4). Mix gelcoat and catalyst mix in your working bucket according to manufacturer's instructions. Add fiberglass gelcoat pigment according to the manufacturer's mixing guide. Be sure to mix the same amount each time you make up a batch. Only mix up as much as you can apply before it starts setting up. Your supplier or the manufacturer can give you estimates of how much you should make up at a time for the type of gelcoat you choose. Always mix up the same amount of gelcoat, catalyst and pigments to get a consistent color.
- 5). Paint the gelcoat on in thin layers if you've decided to use a brush application. Apply all of the compound you mixed up, so it doesn't set in the bucket. If you use a sprayer, add high-gloss additive to thin the gelcoat for spraying. Again use all of the gelcoat mix so that it doesn't set up.
- 6). Cure the gelcoat for at least four hours between coats. The gelcoat will still be sticky when you apply the next layer, whether painting or spraying. Keep working until you've applied three coats. Get the boat under cover and allow the gelcoat to cure overnight before touching the surface.
- 7). Sand the hull lightly using very fine 1000-grit sandpaper on the orbital sander. Finish by lightly rubbing down the gelcoat with very fine steel wool. When you're done, dust the surface with a damp cloth and let it dry. Wipe the hull down with rubbing compound, then buff it with a soft cloth or buffer until the swirl marks disappear, leaving a high gloss shine.
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