Removing Lacquer Without Removing Stain

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A guitar repair job brings up the tricky problem of how to gently remove lacquer from a stained piece. March 8, 2007

Question
Is there an easy way to remove lacquer from a project without disturbing the staining?

Forum Responses
(Finishing Forum)
From contributor M:
It depends on the stain, and are you sure it's lacquer?



From contributor B:
What happened to the lacquer and why would you want to remove it?


From the original questioner:
I am sure it is sprayed-on lacquer. It is on a guitar that I am repairing and I have to remove some to repair the neck and someone sanded down a few high spots, so I thought I would remove all the old.


From contributor M:
Acetone or lacquer thinners will remove the lacquer, but you might want to try buffering either one of the solvents with some mineral spirits so it doesn't effect the stain. (There are no guarantees - you're on your own.)


From contributor W:
Guitar finishers quite often tint their lacquer to produce color. If the maker did and you remove the lacquer, you'll remove the color too. In any case, lacquer finishes are very easy to repair. A little 2 minute touchup in the nude spots with a fine brush, tinted if necessary, leveled and padded over, will usually do the job. Pad some lacquer over those sanded high spots and they'll disappear too. In addition, a fresh coat of NC or CAB lacquer over the whole piece will burn into the existing finish and make the whole thing look like new (or better). In any case, I'd be very sure I had no other options before removing the finish.


From contributor T:
Mix 50% lacquer thinner and 50% wood alcohol. This makes an excellent lacquer stripper and your stain will stay intact. Assuming that there was no shading involved in the original finishing process. Be careful, though, because instruments are finished in a certain manner to ensure quality sound. You may or may not disturb this when you remove the finish.


From contributor M:
I use 50% lacquer thinner and 50% alcohol to remove stubborn dye or pigmented stains. It normally removes all types of stains - the water/alcohol or lacquer and oil.


From contributor T:
Every antique I refinish, I use the 50/50 mix and the stain always remains pretty much intact. Of course, you can use lacquer thinner alone if you want. I apply the 50/50 mix with a soft brush (black chine bristle) only and I lightly wash off the finish. I do not scrub, sand or scrape the finish off; I let the solvents work on their own. Been doing this procedure for 15 years and it works great.


From contributor M:
I usually do it to scrub out the colorants that do not wash off with the stripper. Been doing it for decades. It works pretty good for me. I also find that by buffering, the solvent has less effect on the stains.


From contributor W:
Not to horn in on a debate, but wood alcohol is also called methanol and is very toxic stuff. You won't find in my shop except in the very small quantities used to denature ethanol, and I would never advise anyone to use it.

I do use a process similar to what contributor T describes, but only to reamalgamate a lacquer or shellac finish after it has been cleaned. Acetone for lacquers and ethanol for shellac. Used aggressively, they will dissolve and remove the finish. Used gently, they will partially dissolve and redistribute the finish. (I'd tell you I've been doing this for centuries, but you probably wouldn't believe me and it isn't true, anyway.)



From contributor M:
A little addendum…

"Used aggressively, they will dissolve and remove the finish. Used gently, they will partially dissolve and redistribute the finish."

Acetone, lacquer thinner, or denatured alcohol will easily remove shellac by themselves. To amalgamate (to bring together) defective shellac, which can be done by padding, you can also "buffer" either one of the three solvents so that they are not as aggressive. You will still need lots of skill to perfect the amalgamation.



From contributor O:
I tried buffering my lacquer thinner with mineral spirits and they don't mix. Do you use a blender, or something?


From contributor M:
No, it should go right in, like all the other petroleum distillates.


From contributor R:

Acetone and lacquer thinner and MEK will remove most stains right along with the finish. About the only thing they won't remove as easily is an aniline based dye stain, say something from the early 20's or so. Most oil stains will go bye-bye along with the lacquer coating.

Almost forgot - to remove those stubborn aniline dyes from the 20's style furniture, spray on a soak coat of 409 and work it with a Scotch Brite pad.