How to Use a Wood Hull for a Fiberglass Mold

Using a wood hull for a fiberglass mold is a practical means of making a fiberglass boat. By using a wood hull from a boat, you eliminate a great deal of work because you are not required to develop a core, then a mold, and then manufacture your fiberglass hull. By eliminating two of these three steps, you save time and money. Using a wood hull for a fiberglass mold will give you a fiberglass hull of equal dimensions without damaging the wood hull.

Things You'll Need

  • Covered, ventilated work area
  • Wood boat hull
  • Rubber gloves
  • Fiberglass release agent
  • Dish towel
  • Fiberglass cloth
  • Resin
  • Hardener
  • 5-gallon bucket
  • Stir stick
  • 6-inch putty knife
  • Fine grit sandpaper
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Instructions

    • 1

      Place the wooden boat -- hull up -- in your work area. Put on your rubber gloves Spread release agent over the entire hull of the boat with the kitchen towel. Cover every square inch. Be generous with the release agent. If any part of the wooden hull is exposed to the fiberglass resin, you will damage the wood when you attempt to release the cured fiberglass hull.

    • 2

      Spread fiberglass cloth over the wooden hull. You can let the cloth hang over the gunwale of the boat. You can saw or cut away extraneous fiberglass once the resin cures and your release the hull from the wooden mold.

    • 3

      Mix your resin and hardener in the five-gallon bucket. Spread the resin/hardener mixture over the fiberglass cloth with the putty knife. Take your time; do not leave any bubbles or air pockets between the saturated fiberglass cloth and the wooden hull. The resin/hardener is translucent; you will be able to see the pockets and bubbles.

    • 4

      Allow the fiberglass to cure for 24 hours, then sand the rough or inconsistent places smooth. Apply another layer of cloth over the cured fiberglass and saturate it with resin/hardener. Again, avoid leaving air pockets to maintain continuity and structural integrity. Allow the second layer to cure. Depending on your needs, you can add as many layers as you like. Allow each layer to cure.

    • 5

      Pry the fiberglass hull away from the mold with your hands. If you were generous with the release agent, the fiberglass hull should pop off.