Bubbles in an Epoxy Finish
Tips for preventing bubbles from appearing during the curing for a poured epoxy job, and tips for how to fix it when they do appear. May 7, 2007
Question
I am just finishing up a bar job. I used an epoxy resin finish. It took way longer to cure than I had hoped. Bubbles popped up everywhere, so every 10 minutes or so I had to get the bubbles out. I had it looking perfect. But once it started to cure, the bubbles kept popping up. Now it has almost fully cured, and there are still bubbles and pits from where some of the bubbles were. Does anyone know of anything I can do to fix this? I don’t think adding another coat of this stuff would work. The same problem would arise.
Forum Responses
(Finishing Forum)
From contributor C:
I'm to guess it was the pour-on finish? Did you seal it first?
From the original questioner:
Yeah, it was a pour-on. Yes, I sealed it first.
From contributor A:
I believe in the directions they recommend blowing CO2 across the surface to dissolve the bubbles. The batch I used suggested using a propane torch for the CO2, not for the heat. Kind of wave it across the surface and the bubbles magically disappear.
From contributor B:
You may have poured too thick of a layer at once. Most recommend no thicker than 1/8 thick at a time. Any bubbles that are there will have to be drilled out with a small drill so the resin can fill them on the next pour. I have had them look like Swiss cheese with so many holes, but the holes disappear on the next pour. It is also best to do in a cool area so the resin will cure at a slower rate. The propane torch idea is the best that I have found for removing the bubbles while curing. Make sure you sand the surface lightly between coats.
From contributor C:
I think there were deep pores or gaps that "gassed" out during the pour setup. I try to pour and then quickly sponge a thin layer of epoxy instead of a heavy pour. Also, the torch over the surface as well.
From the original questioner:
Thanks for the info. I’ll definitely keep that in mind on the second pour.
From contributor G:
I have seen/heard the CO2 method with hand-held propane torch myself - this was used in inexpensive pour-on epoxies. Depending upon your local coatings rep, there are a ton of other things you can try.
From the original questioner:
I used the torch method. It worked really well but once the resin started to cure, bubbles still came up. And there was nothing I could have done after it started to cure. I guess I’ll just pour a second thin coat. This is my first time using this finish and in my opinion it’s the worst finish I’ve ever used. Not worth $120 a gallon. Does anyone know of anything else that’s just as durable and that could be sprayed on?
From contributor T:
We have used a few different kinds of pour-on epoxies in the past and they all will bubble. We tried the torch method and had limited success. After scouring the internet for solutions, someone found a product called Eat-A-Bubble. It was purchased through a company called Clock-It.
However, as suggested, the only way to fix your current problem is to drill out the bubbles and recoat. We drill holes and use a large syringe to fill just the hole if the number of bubbles is manageable.
Keep in mind that you can not sand individual areas without changing the sheen. You would need to re-pour the entire surface if you wanted to get the high gloss from the initial pour.
