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mixing pigments

If you have a small repair that you need to color match or you want to create your own color for a project, pigments may be the best way to go.


Pigments can be used to tint polyester resin, vinyl ester resin, epoxy resins and gel coats. There are many colors out on the market.  You can mix a pigment alone or mix with several different colors to create your own color.

liquid concentrate pigment1

We are using an opaque or solid color.  It is a liquid concentrate.

If you add color to a white gel coat, it is going to be more pastel and light colored.  If you are looking for a deeper, richer color, you will want to use a neutral based gel coat or resin.

mixing pigment1

You should mix the pigment with the resin before adding the catalyst. The recommended mix ratio is 6-8% by weight.  You can add up to 10%. We added 5 grams of pigment to 2 ounces of white gel coat. Use a scale to help measure.

Thoroughly mix the pigment and resin so that there will be no weak areas in the end. Scrape down the sides many times and stir until all streaks are gone.

Once the pigment is thoroughly mixed in, add the catalyst.   You can add it between 1 and 2%.  If you are using epoxy resin, it will be the B side.  You will want to follow the instructions on mixing your epoxy based on the mix ratio. Stir completely again.

mixed pigment

You can see in the above picture that the red oxide pigment mixed with white gel coat came out a pastel color.  It made a salmon color which is what we were trying to achieve.  Again, if you are looking for a richer, darker color, you will want to mix your pigment with a neutral based gel coat or resin.