old varnish

[Mike]

I have 28 year old varnished kitchen cabinets, with age greasy fingers have turned the varnish black, crackly. It's soft so easy enough to scrape off but it goes all the way through the stain leaving uneven spots. I would like to avoid stripping as they have decor pieces that would slow doing it right.

I saw some stuff, Acetone I guess, that softened the old finish/stain so it would redistribute. Has anyone tried that? I surely do enjoy working small projects to a perfect Tung finish, but this is a large project with more emphasis on getting it done. Suggestions please? Thanks, Mike

[Mike]

If acetone softens the finish chances are it isn't varnish and regardless of what kind of finish it is the chances of getting a set of kitchen cabinets look anywhere near presentable are slim.

As a general rule the hard way is usually the right way and the right way is usually the way to get a decent job done.Taking the easy way out usually results in a job that looks like you took the easy way out.

[daclark]

A varnish finish can be rejuvenated fairly quickly and successfully by cleaning the surfaces with denatured alcohol. Use a light steel wool on the tough spots, and do not sand. The alcohol will leach the dirt out of the pores and leave most of what is actual patina. You do not need to worry about getting every bit of the old finish off, as new varnish will meld with the old.

[Mike]

I'd have to disagree here.

Varnish, a mix of curing oil, carrier/thinner, resins, unlike shellac or lacquer who's thinners are also their solvents (they dissolve the finish), alcohol and lacquer thinner respectively, has no solvent. When it is cured it is REALLY cured and the only effective way to remove it is sanding, scraping, or using a strong chemical stripper.

That being the facts of the matter, new varnish will NOT meld with old cured varnish. Sanding old varnish will provide a mechanical means for new varnish to grip and hold too old, This is commonly called providing "tooth". The problem is that if the old varnish is aged, chipped, peeling, not only are you putting a new coat on top of one with a dubious bond to the wood but also, since there is no meld, layers have to be built up then sanded back to avoid witness lines.

[George]

Acetone would sure soften lacquer. Pretty common thing to spray on cabinets when.

I think Formby's (Thompson-Minwax) used to have a "refinisher" featuring MEK and acetone, but I never saw a fully favorable review.

[Baron]

MikeG: Thank you for being the voice of reason.

Mike: The existing finish has failed. It must be removed. Putting anything on top of old varnish, without a lot more prep work, will eventually peel off. If a new finish did manage to stick, the underlying varnish will still peel and the whole thing will come off. It is highly unlikely that lacquer is currently on the cabinets. It would have failed in a kitchen environment a long time ago. The finish sounds as though it is so degraded that even acetone is having an effect. ATM (alcohol, acetone, toluene) strippers can soften old varnish but only because the finish is shot.

Good Luck.