Air Bubbles after finishing Stair Treads with Polyurethane
Not sure where to put this post, so I put in both painting and Flooring.
I have a small problem and wanted to ask some advice.
I purchased a new set of treads and risers for my stairway.
I just finishing staining and putting 3 coats of floor grade Polyurethane finish on all of it (satin). I used a good quality natural brush for this DIY. The polyurethane is oil based.
For the most part they look good. I sanded with 220 grit between coats and each coat had less bubbles than the last and was even more smooth.
The problem is that even after the 3 coats there are a couple of air bubles here and there (maybe 4-5 small ones per tread). I'm not sure if that's normal or if there is a way to do a last coat (maybe a different method) to make it all smooth.
I was thinking of a very light final sanding, diluting some polyurethane with mineral spirits and rubbing on a final coat with a lint free cloth (or similar).
Any suggestions? Should I just sand the areas and wipe on a bit in those areas where the bubbles are or just leave it alone because it's normal.
I can't say I've really taken a close look at stained stairs at other peoples houses so I just don't know.
When I went shopping to see how much they were already stained and finished, all the samples were flawless, but maybe the makes sure that all samples are perfect.