Cleaning Old Cabinets Before Re-Finishing

Finishers share their secrets to remove old wax, cleaners, polishes, grease, and grime from existing cabinets before re-finishing. November 25, 2006

Question
Outside of TSP, what do finishers use to clean cabinets before applying a WB lacquer? Some cabinets have built up furniture polish and oils from cooking.

Forum Responses
(Finishing Forum)
From contributor G:
I have used Dawn in water, thoroughly flushed, followed by white gas scrubbed with a purple Scotchbrite. This takes care of most of the contaminants. Oh yeah - being a belt-and-suspenders guy, I also seal with shellac.



From contributor M:
Wash it down with mineral spirits and paper towels, scrub each door until the paper towel is clean, allow to dry. This will take off any wax, polish, or other residue. Then, mix up some liquid detergent soap and water, but use only the suds to scrub it down, and then wipe it dry.


From contributor T:
Mild liquid detergent and water followed by naphtha. I use this order to be sure all of the soap residue is gone. Not sure why you don't want to use TSP unless the existing finish is an NC or CAB lacquer. TSP not only cleans very well, but usually etches or dulls the existing finish, which needs to be done to promote adhesion of your new finish.


From contributor M:
I prefer using the mineral spirits first, because it removes the dirt and grime better than the soap. The solvents do leave a dull look to the finish. The soap suds will remove that dullness and the residue, and will leave a clean surface for recoating, repolishing, or waxing.


From contributor A:
Whatever method you use to clean them, I highly recommend you use a seal coat of either clear vinyl sealer (if this is stain grade) or white vinyl primer (if an opaque). One coat of vinyl followed by one of the appropriate topcoat and you have a nice finish... usually.

Keep a bottle of Fish Eye Killer around. If they have used furniture polish, I don't think anything will remove the silicone enough that I would trust without having the Killer around just in case. Safe beats sorry. I've completely chemically stripped, solvent washed, belt sanded, and vinyl-sealed table tops before and still got fish eye. I dunno if the stuff is invincible aside from the Fish Eye Killer, but it sure seems that way.



From contributor R:
A white scotchbrite type pad dipped into some paint thinner works quite well. For extra tough spots, use a maroon colored one. Once it's squeaky clean, you can follow that up with a cleaning of soap and water. The scotchbrites dull the finish a bit, but that's okay.


From contributor G:
"I dunno if the stuff is invincible aside from the Fish Eye Killer, but it sure seems that way."

Almost sounds like you are considering fisheyes to be entities while they are actually manifestations of contamination such as silicone. Fish eye killer is just silicone that lowers the surface tension of your lacquer and enables it to flow over the contaminated areas. Once you start using it, it contaminates your whole spray system and you either have to flush it out thoroughly or keep using it. Previous discussions along this line have concluded that washing off with gas and lots of rags is the best way to remove silicone from the pieces you're refinishing.



From contributor J:
Will de-waxed shellac stop any silicone from rearing its ugly head?


From contributor G:
Like it says in the disclaimer for the weight loss ads: "Results may vary." Shellac has its uses, but it ain't magic.


From contributor T:
You can often bury silicone contamination under shellac - but you must put on several coats and then keep you lacquer coats very thin, including the last one. You want to avoid the possibility of the lacquer thinner burning through to the silicone, which is hopefully locked below the shellac.


From contributor M:
The more coats you apply over the shellac, the more you will dilute the shellac. After so many coats, the silicone will come right back. If you go over the shellac with another coating, don't push your luck. Quit while you are ahead of the game. You may have to only apply a few coats and then end up hand rubbing and polishing up the gloss on those few coats.


From contributor D:
If anyone thinks the coating they use is silicone-free because you don't add the silicone yourself, you may be surprised (as I was) to learn it is common for a coating manufacturer to add a little silicone to all their formulas. It improves flow out and provides a little built-in protection against minor contamination issues.

And the fact is you can add more silicone sparingly to your coating when necessary to deal with a particularly nagging contamination problem, and having done it that one time does not mean you must add it to every batch from then on.

Though I would hasten to add that in a refinish shop where contamination issues happen regularly for many reasons, it saves time and frustration and it is a good control practice to add a conservative measured amount to all your finish.

There is good reason to add only what silicone is needed, of course. My information is that if you overdo the silicone, it does affect the cure of your finish. Makes sense to me - after all, it is a non-drying oil. However, if used within manufacturer specs, it will remedy 90% or more contamination issues quickly and with little or no downside.

Doing an overcoat job on a set of kitchen cabinets? Follow the cleaning advice and I agree a coat of shellac is a good barrier coat, but I'd be surprised if you don't still have some contamination, so I would absolutely have the silicone additive standing by. I will disclose that I use solvent finishes so I don't know if the additive is different for water base, but I'm guessing any manufacturer of WB finish also sells a silicone additive in some form or another.



From contributor M:

It's true that silicone oil is added to some coatings. It also is added to most aerosol cans as a precaution. Here is an ironic fact - I never heard of an aerosol can causing fisheye to a new, old, or even restored finish. Have you?