Bubbles in Epoxy

Bubbles in Epoxy

Posted by Gayle Brantuk on Jan 9th 2015

So, you decided to build a boat and do the right thing and coat it with epoxy. But, for some reason, when the epoxy dries there are tiny bubbles all over the surface. There are two common causes of bubbles in epoxy. One, air escaping from newly coated wood. This usually only happens on the first coat, but may occur on subsequent coats if the wood is not sealed with the previous coat. Sometimes the bubbling is minimal, sometimes there are lots of bubbles. Why? It could be because of differences in temperature between wood and ambient air temperature, between wood and resin temperature, when the wood is warm... so it could have something to do with temperature. So, what do you do about it? Lightly sand and recoat. If you are going to fiberglass, lightly sand and fiberglass.

Two. The other cause produces bubbles that look more like foam, that make the resin look milky, and can occur any time you apply resin. What causes it? You do. When you use a roller to apply resin (as we do) you may sometimes roll the roller quickly back and forth in order to wet out a particularly stubborn patch of bare wood or cloth. What you are doing is "whipping" the resin. To correct the problem, drag the surface lightly with a brush. The bubbles may migrate out of the resin on their own, if the resin doesn't set up too fast, but if the surface is ultimately going to be clear, it's best to brush them out.

Glen-L stocks three lines of Epoxy. Our proprietary brand, Poxy-Shield ®, System Three SilverTip and MAS Low Tox. We hope you find value not only in the products we sell, but also the thousands of pages of resources for those of you who are or wish to build your own boat.