Finish Your Boat

Your boat must be water-proof so it won't start falling apart during the race! If paint is your final coating, make sure it is at least water-resistant. You want it to be smooth and clean-looking. Here is a good way to accomplish these goals whether you used foam, balsa or a combination.

Finishing Touches

If your boat is made of foam and plastic glued together with water-proof glue, all you may need to do is paint it with acrylic paint. For a smoother finish or for parts made of wood or card stock, here is a more comprehensive regimine.

1. Sand the hull with a medium grit sand paper (100 or so, 220 for foam).
2. Wipe the hull down with a damp cloth getting into all the crevices. Coat the hull with sanding sealer and let it dry on wax paper. Stand it on its rear end, leaning against a support. The idea is to minimize contact with its surroundings. If you are more patient, you can paint one side, dry then paint the other, but a small amount of foreign matter won't matter.
3. Again, sand the hull lightly with a medium grit sand paper.
4. Wipe with a damp cloth. Apply another coat of sanding sealer, dry and sand with fine sand paper (220 or so, 320 for foam).
5. Attach all parts to be finished to the hull. Put transparency film and other plastics on after finishing. Sometimes the order in which you glue, nail or fasten parts can make a difference. Different materials need different glues.
   • Use wood glue for joining wood and paper parts.
   • Use a little rubber cement to bond transparency film to wood (later).
   • Clay sticks fine by itself. Use a toothpick peg if you're in doubt. Drill the fat end of a cut toothpick into the deck structure and let the sharp end stick out. Set the clay on the peg.
6. Apply the first coat of paint. Plastic model enamel paints make a good hard, smooth finish. Use a fine brush with bristles that won't fall out. Use an airbrush if possible. Acrylic paint is our favorite. It is cheaper, easier to work with and clean up. But because it is thicker, it may leave brush marks or bubble if exposed to excessive heat. You will probably need a second coat of enamel.
7. Once the paint is dry, a coat of liquid plastic (polyurethane) or acrylic clear coat brightens up, hardens and waterproofs your finish. Both work especially well with acrylic paint. When drying, lean it against a support. If you move the boat when a pool of resin collects at the base, you can use newspaper under it and it won't stick. Wipe off excess and drips. It collects in pockets and around sharp edges. It may require as much as two days to dry, so be careful not to touch it too soon.