How to Mix Fiberglass Resin

Fiberglass on a black background.
What You'll Need
Polyester resin
Methyl ethyl ketone peroxide
Latex gloves
Protective glasses
Disposable bowl
Wood stirrer
Polyester color paste
Wax powder
Newspaper, drop cloth or plastic sheet

You can use fiberglass resin has many applications, from repairing fiberglass bumpers to creating Halloween costumes. You can also use fiberglass resin to finish and bond fiberglass sheets together.

Fiberglass resin consists of several components that need to be combined. This is incredibly important if you wish to polish the finished fiberglass resin or to color it. Fiberglass resin is a delicate mixture made of components that can potentially cause health issues. It is also important that you mix fiberglass resin in small batches of about 16 ounces. Once it has been mixed, the resin can harden in as little as 20 minutes. The following article will show you how to properly mix fiberglass resin to use in your projects.

Step 1 - Determine How Much You Need

Examine the project for which you need fiberglass resin. It is better to make more than you think you will need, but you still need to make it in small batches. It is a good idea to make it just prior to using it because it will harden quickly; once that happens, you will not be able to use the mixture. Always keep in mind how much fiberglass resin you need and how fast you can apply it to your project.

Step 2 - Mix the Fiberglass Resin

It is important that whatever container you use to mix the fiberglass resin in is large enough for you to easily mix the components. The last thing you want is to overfill a container and have fiberglass resin hit your floor. It will harden, stain, and destroy the floor. For this reason, it is important to use a tarp, plastic sheet, or newspapers to protect the floor or table where you are mixing the fiberglass resin.

Pour the polyester resin into the container first. Make sure the container is free of moisture or dust. Now you can add the Methyl ethyl ketone peroxide to the polyester resin. This is the catalyst that interacts with the polyester resin. Typically you will add an ounce of the catalyst to every gallon of polyester resin. If you are following the small batch rule, then this would translate to 1/8 of an ounce to each 16 ounces of polyester resin.

Insert the stirring stick into the container, and slowly stir the components in the container. Make sure you are reaching the bottom of the container. You do not want the resin to settle at the top. Continue stirring until the mixture becomes the consistency of toothpaste. The fiberglass resin is now ready to be used.

Step 3 - Color and Polish

Before the fiberglass resin sets, you can add in color paste. Consult the bottle to determine the shade you want the fiberglass resin to be after it sets.

If you want the fiberglass resin to have a polished finish, then add wax powder to the fiberglass resin according to the instructions.