This week’s question comes from Zac who asks; “I am sealing a door I stained and I keep getting these little bitty air bubbles. I can sand them off, but they keep coming back. What do I do?”
And my response was: “Hey Zac. Bubbles can come from a few different sources. One can be the wood itself. The pores and pockets on the surface of open pored woods like oak and ash can sometimes trap air, which wants to bubble out after you coat it with finish. You can also introduce air into the finish if there is a lot of air in your brush (if you are brushing). Letting the brush soak in your solvent for a while before using it and being careful not to agitate the brush too much will help quite a bit. Bad brushing technique will also lead to bubbles. So depending on what you are using and how you are using it, the culprit could be a number of things. One of the best ways I know to prevent bubbles is to wipe the finish on with a rag instead of using a brush. You will need to dilute the finish about 50% with mineral spirits or naptha, and as a result, you’ll have to apply more coats. But its well worth it for the smooth finish you’ll get in return. Good luck!