Fiberglassing a Kayak

One important step in building a kayak, whether from wood or a mold, is fiberglassing. Fiberglass gives a kayak its strength and makes it waterproof. When done correctly, a fiberglass job weighs little but makes the boat stiff and strong. On a wooden kayak, correctly laid fiberglass disappears so it looks like only the wood remains. Fiberglass used in boat building consists of two parts: the fiberglass and the resin. The fiberglass looks like a piece of white fabric. You coat the fiberglass with the resin, and when the resin cures, it hardens the fiberglass into shape and adheres it to the surface. Without color additives the fiberglass becomes transparent.

Things You'll Need

  • 6 ounces fiberglass cloth (e-glass)
  • Epoxy
  • Mixing cup
  • Mixing stick
  • Plastic squeegee
Show More

Instructions

    • 1

      Lay the fiberglass evenly across the kayak or into the mold. Try not to stretch the fabric or create runs. If fiberglassing a wooden kayak, don't snag the glass on any slivers. Smooth any wrinkles with your hand.

    • 2

      Mix 2 cups of epoxy according to its directions. Epoxy consists of a resin and a hardener. Once mixed, the hardener heats up the epoxy and causes it to cure into a solid. Most epoxies have a pot life of 20 to 30 minutes, which means that you have 20 to 30 minutes to work with it before it "goes off." It will then become too hot and too sticky to penetrate the fiberglass cloth.

    • 3

      Pour the epoxy on the center of the boat. Starting in the center and working to the ends prevents wrinkles and bubbles created from compressed fiberglass.

    • 4

      Use a squeegee to pull the liquid epoxy across the surface of the fiberglass. By applying light pressure, you work the epoxy into the cloth weave. As the epoxy "wets out" the fiberglass, the glass turns clear. You want the glass to go completely clear. Take note of the time. In a half-hour, you'll return to this section of the kayak.

    • 5

      Continue applying epoxy to the fiberglass until the entire surface "wets out."

    • 6

      Return to each section after 30 minutes to remove excess epoxy. Start at the kayak's center line and pull the epoxy towards the kayak's sheer, the seam on its side. Once at the sheer, any excess epoxy dribbles on the floor. For the first coat, you want to pull enough excess epoxy from the fiberglass to make the fiberglass take a matte and textured appearance. If it turns white, you pulled too much epoxy out. To fix the problem, add epoxy.

    • 7

      Let cure overnight.

    • 8

      Apply a second and third coat to the kayak following the same procedure. The second and third coats fill the weave left by the first coat and take on a smooth and glossy appearance. Let the epoxy cure between coats.