How to Mix Gel Coat for Spraying

Polyester resin is the main ingredient in gel coats.

Gel coats are used to repair damaged or scratched fiberglass objects, and are often used to repair the surfaces of water craft vehicles. You can use a spray gun to apply gel coat resin to fill holes, scratches and tears. Gel coat resin is mixed with an accelorater and a catalyst to form a hard gel coat that imitates fiberglass. Mix gel coat in a well ventilated area to avoid inhalation.

Things You'll Need

• Popsicle stick
• Safety goggles
• Gloves

Instructions

1. Put on protective eye wear and gloves before mixing gel coat.

2. Pour polyester resin into the feed cup on a gel coat sprayer. Unscrew the cap of the feed cup and pour in the polyester resin, filling the cup halfway.

3. Add a small amount of accelerator to the feed cup. Mix the resin and accelerator in the feed cup using a popsicle stick until you get the consistency of a thick gel.

4. Add the catalyst to the mixture. It is recommended that you use methyl ethyl ketone as a catalyst for mixing gel coats. Stir the mixture with a popsicle stick readying the mixture to spray the gel coat on your project.

Tips & Warnings

• Always mix the resin and accelerator first and then add the catalyst to the mixture.

• Wear protective eye gear when working with gel coats.

References

• Plastic Care Inc: Gel Coat Application Guide (PDF)