Water Marks & Rings:
As long as the marks are white or whitish in color, there is a very good chance you can repair the water damage without refinishing. (If the spots or rings turn a dark color, the water has seeped through the finish and into the wood and the damage can be repaired only by refinishing.)
Often, rings are in the wax, not the finish. Cover the stain with a clean, thick blotter, press down with a warm iron, and repeat. Or rub with salad oil, mayonnaise or white toothpaste. Wipe dry and wax or polish.
Heat Marks:
Rub gently along the grain, using a dry steel wool soap pad or a cloth dampened with camphorated oil or mineral spirits, or rub gently along the grain with extra-fine (0000) steel wool. Wipe clean and wax or polish.
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