What You Need to Know About Resins and Solvents

What You Need to Know About Resins and Solvents

Here’s a little-known fact: Even if resins and solvents are marked as kid-friendly, eco-friendly, non-toxic, or claim to have no VOCs, they can still be very dangerous to work with – for your health and for your board.

The Resins and Solvents Experiment – Safety First

Before we start experimenting with resins and solvents, we always make sure we are in a well-ventilated area, and we have a mask.

Lots of resins that are sold in art supply stores and online are sold without warning users to protect their lungs, which is a big mistake.

Whenever you are using resins and solvents, no matter what the label says (no VOCs, non-toxic, etc.) you absolutely need to wear a mask with a carbon filter, wear safety protection, and be in a well-ventilated area or outside.

Traditional Surfboard Resins Vs. The New Epoxy Systems

For this experiment, we used two of the most common resins systems, an epoxy resin system from Entropy Resins and the traditional surfboard resin, polyester resin.

In the last 5-10 years, epoxy has made some major innovations and using epoxy resin systems on surfboards is becoming more and more common.

We mixed the epoxy resin at a 2 to 1 ratio, and it came out nice and clear, with very little fuming.

The polyester resin had actually already gone through a bit of a cooking process with a catalyst, and it has a surface agent in it, so it comes out pretty bright and clear too.

Once the resins were mixed (with their catalysts, not each other), we poured them out over an expanded polystyrene foam (EPS) foam block, as a sample surfboard, to give you an idea of what the reaction process would be on your surfboard.

The Results

In the area where we put the polyester resin, it actually melted away the majority of the EPS foam core.

This is pretty common. We see a lot of customers coming in because they bought a resin system from a hardware store, mixed it up and poured in onto their board. It melts right through, and they end up wondering what happened to their board.

What people don’t know is that there is actually a lot of solvents in certain resin systems, like this one, so you have to make sure you are getting the right resin.

On the other hand, the epoxy resin system from Entropy Resins left the foam underneath perfectly fine. There are no solvents in this resin system, so you don’t have to worry about it ruining your board.

In fact, this epoxy resin system is so safe you can use it on most substrates.

But, be careful: In our experiment, we poured some epoxy resin into a large hole in the foam and ended up with some problems. When you try to fill a hole that is too big, you end up getting an exothermic reaction from the epoxy.

An exothermic reaction releases considerable heat when the epoxy resin is combined onto itself at a higher mass. The more or higher mass of epoxy resin you pour into space where it will be resting on top of itself, the quicker it will heat up. This can cause a melt in your board.

Solvents: The Good, The Bad and the Ugly

Speaking of melting your board, if you are trying to remove dust or debris off of your surfboard, you may be tempted to use acetone or nail polish remover.


If you aren’t using the right solvents, you can melt a hole right through the middle of your board.

For example, during out experiment, a teaspoon of acetone made a fist-sized hole in our demo board. This will absolutely ruin your board, or at least require some major reconstruction.

Instead, use denatured alcohol, or rubbing alcohol. It tends to be a lot gentler on the foam and is our recommended cleaning system for major jobs.


When looking for and using resins and solvents for your surfboard or art DIY project remember:

  • Always wear a mask with a carbon filter when you are using resin systems
  • Make sure your area is well-ventilated
  • Choose your resin carefully: hardware store resins and traditional resins can be loaded with solvents that will melt right through your board
  • Make sure you are picking out a resin system that is compatible with your substrate
  • Avoid filling holes that are too large with resin, or you will cause major damage
  • Do not use nail polish remover or acetate for cleaning jobs

To check out our selection of specially formulated epoxy resins with cutting-edge eco-friendly technology, visit our products page here.