Bubbles in my cured surface
Why do I have bubbles in my final cured surface and how do I fix these?
Some types of wood are very porous, are difficult to seal and may take several seal coats to properly seal correctly before applying the flood coat. Barn wood, knotty wood, rough wood, planks, and wood with holes or cracks can take two to three seal coats to prevent air from coming up into the flood coat. One seal coat may not be enough and will result in bubbles that surface into the flood coat even after you pop them. The surface may look perfect after you use the heat gun or plumber's torch but when you return at a later time you end up with bubbles that have surfaced and cured in the flood coat. The photos below show the result.
How to fix:
1. If you can live with the deeper bubbles that are trapped in the epoxy you can do a very light sanding. Then you wipe with acetone. Give the acetone 30 minutes to evaporate. Apply another seal coat to fill in the craters and surface bubbles. The wood should be sealed at this point. Wait 4 to 6 hours and then do another flood coat.
2. If you want to remove even the deepest bubbles you can do a heavy sanding, removing most of the flood coat that was applied until all the trapped bubbles are sanded out. Then you will clean with acetone and wait 30 minutes for it to evaporate. Apply a seal coat, wait 4 to 6 hours. Apply ANOTHER seal coat, wait 4 to 6 hours. Apply a flood coat. We recommended 2 seal coats so that you do not have to do this again.