Proper care and maintenance of the gelcoat will keep your boats luster and underlying fiberglass in good condition.   Read these tips for maintenance and repair advice on everything from cleaning to repairing cracks.

What is Gelcoat?

The deck and hull are made of fiberglass covered with gelcoat. Gelcoat is a scratch resistant, color-pigmented, polyester resin. With normal use, some damage to the gelcoat should be expected.

Gelcoat ApplicationCrownline Lamination ProcessHull Mold Pull

IMPORTANT: Foot traffic on soiled fiberglass surfaces will severely scratch and mar the finish. Keep the fiberglass as clean as possible.


What products Should I Use To Clean My Gelcoat?

3M™ carries a complete line of fiberglass care products such as:

3M Gelcoat Products

3M™ Perfect-It™ Boat Wax keeps all sorts of surfaces looking great. It’s safe for gelcoat, paint, fiberglass, and metals and has a pleasant tropical scent. The pure wax finish protects against the elements.

This fast-cutting compound removes heavy oxidation, scratches, and other defects. Use 3M™ Perfect-It™ Gelcoat Heavy Cutting Compound for any P800 scratches or finer.

Take a look at this guide to find the right products for you. 3M Product Guide


Repair Minor Gelcoat Scratches

Minor scratches can be repaired with car wax. Treatment will repair or lessen scratches.  Apply wax to a damp, soft cloth. Rub the gelcoat surface gently with the cloth in a circular motion.


Repair Chips, Hairline Cracks and Small Patches

Gelcoat Damage

Gelcoat that matches the color of your CROWNLINE can be purchased at your CROWNLINE dealer or at To match the color exactly, specify boat model, name, color
and year manufactured.

IMPORTANT: Air temperature must be above 65°F (18°C) to apply gelcoat. The area must be clean, dry and free from oil or wax before attempting to repair.

  1. Sand damaged area with #50 sandpaper, or use a power drill with a burr bit. Round out and feather edges.
  2. Remove all flaky edges. If surface damage covers a large area, a power sander may have to be used.
  3. Cleanse the area with rubbing alcohol or acetone after you have completed sanding
  4. Place one teaspoon of gelcoat on a piece of wood or cardboard.
  5. Add two or three drops of hardener. Mix for 10 to 15 seconds using a spatula or knife.
  6. Apply gelcoat to damaged area. Fill in slightly higher than surrounding surface.
  7. Cover with wax paper or clear plastic and smooth to the desired contour.
  8. Allow an hour or two to dry completely.
  9. Remove wax paper or plastic.
  10. Water sand with #600 wet or dry sandpaper.
  11. Buff repaired area with buffing compound, then follow with wax and polish.

IMPORTANT: If using a power buffer, keep the buffer moving. DO NOT pause in one area too long. This can cut into the boat’s underlying surface.


Watch Crownline Video on Why Our Gelcoat has the highest luster rating in the industry

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