Q: I recently sanded down to bare red oak floors Wednesday. I put down the first coat of oil based high build gloss poly Wednesday night. All looked decent. I did a light sanding with 150 grit this morning and cleaned and re-coat. I look now and I see tons of little scratch marks all over.
I do not know what to do at this point to get rid of the scratches if anything. Please help. Thank you.
A: You will need to buff it all down and apply another coat. I would recommend a lower shine, say satin which looks very nice and is easy on the eyes. Gloss is particularly unforgiving when it comes to things like little scratches.
Follow-up: OK. Thank you. I was going to use 220 grit in Palm sander then reapply with satin.
A: You should be fine. Just make sure you thoroughly buff the entire floor. 220 is more than fine enough. I often use 180 grit with no issues.
Follow-up Q: Okay thank you. Is buffing different than sanding using 220 grit sandpaper?
A: Not necessarily, though sanding generally can invoke the idea of removing all finish to clean wood. Buffing or lightly sanding with the intent of scuffing or scratching the existing finish coat to gain adhesion is what we are aiming for. Accomplished with the finest abrasive that will do the job, thereby minimizing visible scratches.
Related Q: Hello. We at redoing our hardwood floors for the first time. After sanding and cleaning we applied old masters penetrating stain with a rag. Then we applied satin polyurethane with a brush. After the poly dried we noticed several little bubbles that we sanded down with 120 grit sandpaper. Now we have sanding marks all over the floors and I am worried that if we apply another coat of poly the marks will show through. How can we fix this before we put another coat of poly on? Thanks!
A: When applying more than one coat of polyurethane you must sand or buff between coats with a fine abrasive to gain adhesion between coats. So scratching is part of the process. The idea is to have scratches fine enough that a good finish will cover and hide them. After thoroughly buffing the entire floor, being careful not to cut into the stain, clean up and apply another coat following the spread rate of the finish which is generally 500 sq. feet per gallon. You may want to use a top quality finish such as Poloplaz Primero satin. It’s is a great product to apply with a 3/8 or 1/4 pile roller.