Modern Pianos are finished with a variety of materials, from traditional lacquer to modern polyurethanes and polyester resins. Whatever the material, a piano finish is designed to protect the wood from dirt and liquid spills, reduce the damaging effects of humidity changes, and -- in the case of clear finishes -- enhance the beauty of the wood.
Modern finishes are designed to do their job without the additional aid of polishes or waxes. In most cases, a piano finish is best maintained by simply keeping it clean and avoiding exposure to direct sunlight, extremes of temperature and humidity, and abrasion.
1. Avoiding finish damage.
- Your piano's cabinet, like all woodwork, is subject to expansion and contraction with humidity changes. Excessive wood movement can eventually cause the finish to develop tiny cracks and even separate from the wood. Moderating the temperature and humidity swings around the piano will help to preserve its finish as well as its overall structure and tuning stability.
- Locate the piano in a room with a fairly even temperature, away from drafts, dampness, and heat sources. ALWAYS AVOID DIRECT SUNLIGHT -- it will age the finish prematurely and cause color fading.
- To prevent scratches, never set objects on your piano without a soft cloth or felt pad. Never place plants or drinks on a piano, because spillage and condensation can cause major damage.
2. Dusting your piano
Dust is very abrasive, and can scratch the finish if wiped off with a dry cloth. To avoid scratching, dust the piano lightly with a feather duster. Alternatively, wipe lightly with a soft damp cloth to pick up the dust, followed immediately with a dry cloth. The cloths should be soft cotton such as flannel, because coarse or synthetic fabrics can scratch some finishes. Wring out the damp cloth thoroughly so it leaves no visible moisture on the surface.
To avoid creating swirl marks, always wipe with long straight strokes rather than circular motions. Wipe with the grain for natural wood finishes, or in the direction of the existing sheen pattern for solid-color satin finishes.
Because some exposed parts inside your piano are fragile, it's best to let your technician clean these areas.
3. Cleaning the finish.
To remove smudges and fingerprints, first dust using the damp/dry cloths as above. If heavier cleaning is necessary, dampen your cloth with a small amount of mild soap solution. A common product is Murphy's Oil Soap, available at most grocery and hardware stores.
4. To polish or not?
Before using polish on your piano, be sure it is actually necessary and beneficial. In general, most manufacturers recommend against using polishes because of the potential for damage to the finish and contamination of other parts of the instrument.
Common household products such as "lemon oil" or inexpensive "furniture polish" should be avoided. Despite the labels' claims that they "protect" the finish or "feed" the wood, they offer no protection from scratching and can actually soften the finish if over-used. Worse, they often contain silicones and oils that contaminate the wood, complicating future refinishing or repairs. Silicone is especially dangerous because of its tendency to spread within the piano, sometimes causing extensive internal damage. Avoid aerosol products altogether since the over-spray can contaminate piano strings, tuning pins and action parts.
An appropriate polish can help to restore luster to a dulled finish or reduce the tendency of some finishes to show fingerprints. However, it should be applied sparingly and infrequently, and all excess should be wiped clean with a soft dry cloth so no visible film remains. To prevent scratching, always dust before polishing. Specific recommendations follow.
5. Removing a heavy polish build-up.
If your piano's finish appears gummy, oily, or streaked, it may be contaminated with too much or the wrong type of polish. Adding more polish will not correct this problem. Instead the finish should be thoroughly cleaned, then evaluated for any further treatment.
To remove accumulations of old polish, use a cloth dampened with a mild soap as in item 3 above. Wring the cloth thoroughly to minimize wetting of the finish, and dry the surface immediately. Test a small area first to make sure the washing does not cause white marks or softening of an older finish.
If stronger cleaning is necessary, look for a product called "wood cleaner and wax remover" at hardware or wood workers supply stores, or ask your technician for a suggestion.
Once the original finish is clean, you can either leave it as is or enhance the gloss and clarity with an appropriate polish according to the finish type listed below.