Duane Goldman's product is excellent, and I'm glad to learn that he
now makes available (?) a stronger potion, since the regular version 
is not very effective on extremely heavy fatty acid deposits, even with 
repeated applications.

I can tell you ammonia (active ingredient in Windex) does work, but it
is not as effective as mineral spirits (paint thinner), or naphtha (Ronsonol
lighter fluid).  Be careful not to breathe the fumes!

I have used all these solutions and have never noted any deleterious
effects on the lacquer, but I've not made a scientific study of the matter.

Doug Pomeroy
Audio Restoration and Mastering Services
193 Baltic St   
Brooklyn, NY  11201-6173
(718) 855-2650
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