Dulling Down a Poly Finish

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It's hard to remove gloss by sanding or polishing. A new topcoat may be the only practical answer. July 3, 2008

Question
I'm building a large square coffee table for a customer who has four children. She wants a "bullet-proof" finish, so after the stain, I brushed on layers of polyurethane starting with a couple coats of semi-gloss for depth and finishing with several coats of satin. She wants a satin look. I polished out the minor imperfections (dust particles, etc.) and was left with a mirror-flat and highly reflective surface, yet the depth of the finish is clearly light-diffusing, satin. It is beautiful.

Unfortunately, the customer sees it as too glossy and wants me to dull it down a bit. I rubbed it down with 0000 steel wool and paste wax as recommended here. Now it is glassy smooth with super-tiny swirl lines in it. This looks unsatisfactory to me. Before I cut it down a layer with 400 or 600 grit and re-coat with satin (and no polishing), can anyone tell me what else I might do to return it to a satin finish? Second question, if I do have to resort to recoating, how do I make sure I've removed all of the past wax from the previous step?

Forum Responses
(Finishing Forum)
From contributor D:
The finish your client is most likely looking for is an off the gun finish. Anytime you polish out a finish to a "mirror" finish, it would be hard to consider a "satin". Even though in your trained eye it may show the light diffusing characteristics of satin. This is not what your client sees.

Clean the table with VM&P Naptha or mineral spirits really well and sand the surface. Be careful, Poly needs a tooth to bond with the previous layer so don't sand with too fine a grit.

I would lay down a barrier coat of shellac to isolate any missed wax contamination. Apply a final coat or two of your poly. Dust free is an issue with poly, as you have seen. Water based poly may give you a better chance at dust free.



From the original questioner:
You told it just as I thought. I wanted to avoid that much of a redo, but I know it’s the right thing to do. Perhaps I should sand with 320 then?


From contributor J:
Before refinishing try rubbing it out with rotonsone or pumice with oil or water. You'll get different sheens with different combos of those. Even 0000 steel wool with a gel like Elbow Grease can give a nice low luster hand rubbed look.


From contributor K:
If you use Shellac as a barrier make sure it's de-waxed. SealCoat works well. I'm not familiar with " Elbow Grease" gel but I assume it's like Mohawks Flat Lube or "Steel Wool Wax" both of which work well.


From contributor C:
As to the swirl marks – don’t use an orbital machine. Sand it straight line or do it by hand in straight lines with steel wool or sandpaper - that's real elbow grease! The look is what used to be called a hand rubbed satin finish long before the use of matting agents in the coating were used. Oil modified polyurethane is a good finish but it's not bullet proof by far.


From contributor A:
320 is too fine for sanding between coats of oil based poly. There is no chemical bond only mechanical. Like Contributor D mentioned it needs tooth. 220 grit would be a better choice.


From the original questioner:
My issue with using paper courser than 320 is that cross-grain scratches show through thin coats. Heck with 220, even "with grain" scratches show through. In order to hide the scratches, I need to make my coats thicker and then I'm back to the original problem. I'm beginning to understand why so many abhor the use of poly.

Regarding the comments about rubbing out with various methods including steel wool: I've used every combination listed and what is left is a mirror-smooth (and therefore light reflecting) finish that has micro-swirls rather than a matt/satin finish as in an off the gun finish that DCS describes.



From contributor C:
I don’t think in the terms of bullet/child proof there is no such thing. But if that’s what the client wanted I would use a pour on finish epoxy, etc, like you find on tables in restaurants. Personally though for my table - I use Tung oil only, which can be easily repaired and kept looking like new forever (as long as the top is solid wood).

It's seen heat damage, dents, gouges, markers, paint, spills of every kind, including fingernail polish and still only looks bad when I don’t have the time to do any repairs. Outside of that it always looks good. But for arguments sake not even a glass top is bullet proof



From the original questioner:
Those are excellent points. I think I may have been the victim of effective marketing; re: polyurethane. Everything I made for the first 20 years (hobby woodworking) was finished with tung oil finish. More recently I've used other oil finishes (boiled linseed, danish, etc) with similar results. As I have worked to get this particular finish exactly right, I realize what a PITA it is (and nearly impossible in some cases) to change the look effectively, repair and or recoat without significantly cutting down the previous layers.