How to Test Gelcoat

If you purchase a boat, kayak or other vehicle designed for the water, the hull will be shiny, brightly colored and will effectively protect your boat from the water. However, over time the color will fade and the hull coating may develop cracks, scrapes or other types of damage. A coating, known as gel coat, is easy to purchase. It often comes in a repair kit, which will include everything you need to repair small amounts of damage. Testing to see what color matches your boat is largely a matter of trial and error.

Things You'll Need

  • Masking tape
  • Soap
  • Water
  • Acetone
  • Handheld rotary tool
  • Gel coat repair kit
  • Plastic cups
  • Craft sticks
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Instructions

    • 1

      Tape off the area that you want to repair with masking tape or painter's tape.

    • 2

      Wash the area thoroughly with soap and water. Wipe down the area with some acetone, as well. This will strip away contaminants and some of the gel coat, enabling you to see what the original color was because gel coat fades over time.

    • 3

      Widen any cracks with a handheld rotary tool. This will ensure that you get gel coat into the bottom of all cracks once you make the repairs. Wipe away any dust.

    • 4

      Mix a very small amount of gel coat in plastic cups with the craft sticks according to the instructions on your kit. Start with a white gel coat, then add small amounts of color, using more color in each cup to get a variety of shades. A small amount of pigment adds a lot of color. After adding and mixing in the color, use the craft sticks to smear a small amount on the hull, close to an area that has been cleaned with acetone. Do several tests, adding more color each time. Write down the color ratio that you used for each test so that you can duplicate a color again later.

    • 5

      Cover the test patches with plastic wrap. The kit may include plastic for this purpose. Wait for the test spots to cure, then examine them to see which one best matches the hull. It is nearly impossible to get a perfect match, but you can mix a color that is very close and will be almost indistinguishable from the rest of the hull.

    • 6

      Use your notes to determine how much color to add to the gel coat when you make your final repair.