How to Fiberglass

by Contributor

This article will explain how to fiberglass. Learn how to use fiberglass to repair, build, and work with this useful material.

First, decide what it is you want to fiberglass and how much material you will need. Fiberglass is ideal for repairing or building components for your car or boat. If what you are constructing is structural, use thicker fiberglass (24oz or more). If you are building something for cosmetic purposes, 8-14oz fiberglass will work well.

Next, prep the surface for where the fiberglass will be bonded to. Sand the surface with heavy grit sandpaper. This will help create a mechanical bond. Then, wipe the sanded surface down with a solvent, such as acetone. This removes all dirt and grease.

Now, take your fiberglass and lay it over the area to be glassed. Cut the cloth to the correct size, and be sure to allow an inch or so for any overlaps. This is especially important on fiberglass repairs. Lay the cut fiberglass where you want it to be located.

You are now ready to impregnate the fiberglass with resin. Follow the resin instructions for mixing, estimate how much resin you will need, and mix in a plastic bucket. Either pour the resin on the fiberglass, or apply with a paint brush. Use a plastic squeegee to skim out excess resin and eliminate air bubbles.

Once the fiberglass cures, you can repeat the last steps and add more layers for extra strength, or you can sand and polish the fiberglass making it smooth. As soon as the fiberglass is a smooth as possible from sanding, do another acetone cleaning of dust and grease. Your fiberglassed component is now ready for painting.


  • check Fiberglass in a cool environment, warmer temperatures will cause the resin to "kick" faster.
  • check When sanding fiberglass, work your way up to higher grit content.


  • close Be careful what you mix the resin, certain resin will dissolve foam.
  • close Be careful, follow safety instructions, and avoid flames.

Items you will need

About the Author

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