How to Lay Fiberglass Cloth

Fiber Glass Cloth Has Many Applications

Fiberglass is a popular material to use in repairing auto bodies or making lightweight replacement parts. It can also be used for boats, motorcycle fairings and more. Working with fiberglass can be difficult if you do not have a basic understanding of how to lay fiberglass cloth. It is a process that is deceptively simple but requires time, practice and patience.

Things You'll Need

• Fiberglass cloth
• Scissors
• Fiberglass agent
• Paintbrush (or paint roller)
• Plastic spreader

Instructions

1. Lay your dry fiberglass cloth over your mold or repair area, and cut enough cloth so it extends 2 inches past the edge of either.

2. Soak the fiberglass cloth in your fiberglass agent; a quick and thorough dunking is enough. Fold your wet fiberglass cloth in half and lay it into the mold or repair area so the center of the cloth meets the center of the area. Slowly lower the outer edges of the cloth while spreading the cloth over the area.

3. Smooth the cloth and make sure that every inch of it is impregnated with fiberglass agent, using a paintbrush or a paint roller (if you have a large piece of cloth), quickly working from the center out. If it needs more, just dip your brush or roller into the agent and apply.

4. Use a plastic spreader, again working from the center out, to force any air trapped beneath the cloth to the edges. Pull the spreader from the center all the way to the edge, chasing the air out. When no air bubbles can be seen beneath the cloth, let the fiberglass dry and harden into shape.

Tips & Warnings

• Cut a 12 by 12-inch piece of fiberglass cloth and, using an old coffee can as a mold, practice applying and smoothing the cloth before you commit to your larger project.

• If you are using a mold to make a fiberglass part, make sure you apply releasing agent to the mold first before you lay fiberglass cloth.

References

• Fiberglass part making

Resources

• Read this Article in Spanish
• Use Foam to Make Your Molds