Q: My mahogany dining room table had a built-up layer of wax and polish, so I used paint thinner in an effort to remove the accumulation. It seemed to do an excellant job, but now when I try to apply new polish, it looks great for an hour, then seems to separate and become streaky and unsightly. Can you suggeste anything to overcome this?

A: I think you probably didn't remove all the old polish wax, or there may be at least a residue of the thinner still on the surface. Start over nd wipe the top with paint thinner again. This time work only a small section at a time, and make sure you saturate the cloth with clean thinner each time. Don't dip the cloth into the same container. Change cloths frequently, and as each section is cleaned, wipe with a second, clean dry cloth immediately after using the solvent.

Q: New paneling was recently put on my walls and I have hung a number of paintings and pictures on these walls. I am worried about light and dark discolorations that may develop on the panel areas behind the hangings after a time. Is there anything I can put on the paneling to prevent this?

A: Most of the darkening and change of color that takes place are due to a lack of air circulation behind the pictures, plus the buildup of dust and grime in an uneven pattern that results from part of the wall being covered. A high percentage of this can be prevented by a simple trick: Prop the pictures and paintings slightly away from the wall by putting some small rubber bumpers on the back of the picture - one in each of the lower corners will do the trick, since the top tends to hang slightly away from the wall in most cases. CAPTION: Illustration, no caption, By Mary Myers for The Washington Post