How To Fix The Fiberglass On A Boat

Boat owners who know how to fix the fiberglass on a boat will find that they can easily do repairs and even learn to modify their boats as they wish. Fiberglass is very simple to repair. Those who do work with fiberglass should be sure to follow proper safety procedures as well as proper disposal procedures to handle the waste and chemicals used with the fiberglass. Though small repairs on fiberglass can be done using commercial products, it is larger repairs that will be discussed here.

To fix the fiberglass on a boat, you will need:

• Woven fiberglass
• Resin
• A catalyst
• Acetone
• A 2" brush with wooden handle
• Paper bowls or cups
• A die grinder with a diamond cut blade
• 40 grit sandpaper
• Masking tape or C clamps 
• A large piece of cardboard or plywood
• Wax 
• Safety glasses

1. Prep the area. In order to fix the fiberglass on a boat, you first need to prepare the area. Since you are repairing the fiberglass only at this point, it's best to work from the inside of the boat. Cut away the damaged fiberglass with the die grinder. You can do this by using the edge of the die grinder blade and grinding away any parts of the damaged fiberglass. If there are any cracks, follow them with the die grinder as well. In part, you are roughing up the area to be repaired so that the new fiberglass with adhere to it. Sand areas outside of the immediate repair area with the 40 grit sandpaper.
2. Give support to the fiberglass. When you fix the fiberglass on a boat, you will need to give some form to the fiberglass. Cardboard and masking tape are fine for smaller areas. Otherwise, use the C clamps to affix a piece of plywood to the boat so that it completely covers the area to be glassed. Wax the cardboard or plywood before affixing it to the boat so that it can be easily removed from the fiberglass later. Car wax actually works fine for this as long as it is put on thick.
3. Mix the resin. Add the catalyst to the resin per the instructions and measurements provided by the catalyst manufacturer. Note that as soon as you mix these two chemicals together a reaction begins, and the resin starts to "set," or harden.
4. Apply the resin and the fiberglass. To fix the fiberglass on a boat, you first must apply the resin to the support for the fiberglass and the surrounding areas. Lay the woven fiberglass on top of the resin. Cover the fiberglass with resin by dabbing it on with the brush. Use the brush to push out any air bubbles that exist between the support and the fiberglass as well as the existing fiberglass and the new fiberglass.
5. Clean up. Allow the fiberglass to set up. Clean up tools as needed using acetone. Once the glass is set, remove the support.