Final Buffing in Place for a Poly Cabinet Finish
Pros suggest brown paper, buffing pads, and other options. September 16, 2008
Question
I'm having to re-do some cherry kitchen cabinet doors that do not meet the zero defects of a pesky homeowner. We have sanded the doors with a 400 grit pad and had them smooth as baby's skin. We then recoated with Semi-Gloss fast drying Min-wax using a HVLP touch-up gun with a 1.0 MM tip with 21psi. The finish came out looking very smooth, but has a slight drag on the surface when you move your hand across the surface.
Not being experienced in the finer points of finishing, I could use some suggestions on what to do to make the next coat smoother. I read about adding flotrol in the next coat. Is that something I need to consider or are their some other tricks? Any tips are appreciated.
Forum Responses
(Finishing Forum)
From contributor A:
Flotrol may help you with your incontinence, but alias it will not have a positive effect on your Minwax poly. Floetrol is an additive for latex paint. Penetrol is an additive for oil based paints/varnishes and poly. Oil base poly doesn't like to stick to itself. Sanding beyond 240 grit may cause adhesion problems. Poly is thinned with naptha.
From contributor J:
Have you tried just wiping them down with a brown bag?
From contributor W:
Try buffing them out with a soft cloth like an old t-shirt. If that doesn't work hit them with the 400 again or 000 steel wool. Then re-coat with poly, rub on or even a foam brush. Wipe off with soft cloth before it dries (almost immediately) turning frequently and buffing dry. Use plenty of fresh rags.
From the original questioner:
To contributor W: Are you saying, if the initial buffing doesn't work, re-sand, apply a light coat of poly and then while it is still wet, polish it off with a soft rag?
From contributor W:
Yes.
From contributor W:
Also it won't hurt to try it on the back of the door or a hidden spot first just to make sure you get the desired results.
From contributor P:
Contributor J had a good idea. Wiping them down with a brown bag or "back-papering" is a technique long used to smooth almost perfect surfaces. I've never done it with poly, but in my experience it does well with lacquers and conversion varnishes. We use the back of our sandpaper sheets or masking paper with good results most of the time. At no cost, it's an easy thing to try. Try it first on a back though.
From contributor O:
What sheen of finish are these cabinets? Flat, gloss or semi-gloss?
From the original questioner:
Semi-gloss.
From contributor O:
Use a Mirka Abralon 2000 grit pad on an air orbital sander (like a Dynabrade) with a little mist of water and wipe dry with a soft cloth.
From the original questioner:
To contributor R: I have a Porter cable Random Orbital sander with an RPM between 2,500-6,000. What is the best speed to use with the 2,000 grit paper? Will this process leave any marks or burn spots on the panel? How long should I wait after spraying before I begin the buffing process? Thanks for the suggestion.
From contributor O:
Electric sanders and water don't mix well sometimes. Be careful and keep water to a minimum. You are not sanding that hard just polishing off the grit so do less than you think you need. You can always go back again.
You may want to try this on a door back or somewhere less visible till you are comfortable with the process. It is really easy and looks great. You should not see any scratches unless the doors are very dark or black.
If you get the Abralon starter kit there are grits ranging from 180 to 4000. If you need more gloss just step up to the next grit. If you leave burn marks you are trying way too hard.
