Q: I have a beautiful 50-year-old, ebony-finish concert piano that is well kept with a shiny finish. However, on top there are several spots where wrinkles have developed and I am afraid the ebony finish may crack soon. What can I do to improve the appearance and prevent cracks in the finish?

A: I am not sure what you mean by wrinkles that have developed. With old piano finishes you sometimes get a condition where the finish checks or develops minute splits, so I assume this is what you mean. This is caused by aging of some finishes, which become brittle and "alligator" (split and check). Sometimes this can be stopped by a process known as amalgamation - the surface is carefully and lightly wiped with a lacquer thinner. This thinner actually starts to dissolve the finish so it blends back together again.

This has to be done skillfully without leaving the solvent in one place too long, and without rubbing too hard. Frankly, on a valuable piano I think this is a job for a professional finisher - but if you want to try, start in an inconspicuous corner and try rubbing lightly with a lint-free cloth dipped into the thinner. This will likely remove some of the gloss so the finish will then have to be repolished.

Q: Because of a breathing problem I have to use a vaporizer each night in my bedroom. For the last year or two this has caused an accumulation of some dark material in some of the corners, behind the furniture and mirrors and on the ceiling. It washes off, but comes back when we use the vaporizer again. Can you tell me what these discolorations are and how to avoid them?

A: The discolorations are almost certainly mildew caused by the excessive humidity and warth in the room. You can remove it by washing with a solution of one part fresh laundry bleach mixed with three parts water. This will kill the fungus, but it will came back if the present lack of ventilation continues, coupled with the excess moisture from the vaporizer. It will help to ventilate the room as soon as you get in the morning and shut the vaporizer off. Also, wipe down any dampness you see in the morning instead of allowing it to remain. After you kill the mildew, repaint with a paint that has extra mildewcide added (your paint store should be able to help you with this).

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