Q: We discovered under layers of vinyl that our 100 year old kitchen has a Douglas Fir floor. We had a floor man refinish with no stain, 3 coats of satin Bona varnish. The 3rd coat ‘bubbled’ in an area and so he came back to sand. He used paint thinner to eliminate any possible contaminates, then re-coated.
The bubbled area is barely noticeable but now there are 2 issues: 1) There are 2 index card size areas where it appears the varnish didn’t adhere. 2) There are sand-like particles in many places and a couple of tiny hairs embedded in the finish. He is coming back tomorrow morning to re-do this rather large kitchen floor (18′ x 22′) and having used him several other times, I think he’s good – what’s going on with this project?
A: I don’t believe the bubbling was caused by contaminants as in chemical contaminants. He may have had air flowing across the area that bubbled. If it is in front of a refrigerator that would be likely.
Also grit and hair indicates the area is not as clean as it needs to be. Wipe the floor down with a micro weave mop after a thorough vacuuming and then coat.
I would not have used mineral spirits when applying water born finishes. If it is not 100% dried and evaporated it will cause adhesion issues.