Keeping your zither in top shape will increase your enjoyment when practicing and performing and will ensure that your instrument is preserved for years of use. At the 1993 FIGA Convention in Schaumburg, Illinois, Leonard Zapf Sr. presented words of advice to the zitherists in attendance, gained from years of experience as a zitherist and instrument repairman at Zapf's Music Store in Philadelphia, Pennsylvania.
In comparison to all other string instruments that are mostly very sensitive to temperature, humidity and other extremes, the Zither usually has a more stable construction and often stays in good playing condition during extreme circumstances. It is good practice, however, to help your instrument stay in A-1 condition (that includes appearance, staying in tune and playability) by getting in the habit of doing certain things to accomplish this.
1. The Fingerboard:
The fret of the fingerboard are placed in their exact position (with plus or minus 1 to 2/100 of a millimeter). The top edges of the frets will eventually be slightly notched, especially by the steel A strings. This process is greatly accelerated if the strings are rusty. The notches can wear deep enough to cause a buzz on the next fret. This wear can be significantly reduced (especially on the A strings) by wiping all fingerboard strings with a small cloth soaked with a fine clock oil after each practice or playing before you put your instrument in the case. If a player uses unusually strong pressure on the fingerboard strings this also can cause a more rapid wear or notching of the frets. (Players get into this habit if the strings are too high over the fingerboard). From a playing point of view this is not a good habit to get into, since it slows your playing speed. A light touch in your left hand will increase your finger dexterity and will result in a longer life of your fretboard frets. Nevertheless, after a long time of use it eventually will become necessary to rework your fingerboard. This is called a fret level and recrowning of the frets. This is not a job for amateurs and should be done by skilled people who know how. It is possible to repeat the process about 10 times on a fingerboard (if done correctly) before replacing the entire fingerboard or replacing the frets in the old fingerboard. A word about old instruments: the frets on them were installed in such a way that you can not just pull them out without tearing the wood out around them also, thus destroying the fingerboard.
2. The Tuning Pins:
The tuning pins have a fine left handed thread. They turn themselves deeper into the pin hole when you restring or tune (raising the pitch) and turn themselves out when taking the string off or lowering the pitch. The pin block is usually made of Beechwood and after years of use might wear to a point where the pin does not hold the tuning of the string anymore. Attention must also be paid that that pins are deep enough in the pin hole. The normal protruding pin height is approximately 21 to 24 millimeters. If the pin still does not hold you can insert a thin wood shaving into the pin hole and screw the pin in with normal down-pressure. The excess shaving still sticking out can be broken off. If this does not correct the problem you can also replace the loose pins with heavier pins (Reparatur Wirbel), but this should again be done by a skilled mechanic. Never use oil polishes or any oil near the tuning pins.
3. The Finish:
If you completely restring your instrument it is the best time to freshen-up the finish. There are many Guitar polishes available that are safe for Zither finishes. You can use lukewarm, thin soap water on a soft cloth first. Some dull spots from little droplets of sweat or a sneeze, etc., might remain and are sometimes impossible to remove. Using Martin Guitar polish after that or even Pledge furniture polish will do. Never use Alcohol or thinners which might soften and destroy the finish. If the strings are on the instrument it is a good habit to use your Zithr brush (also with a soft dry cloth around the handle) to remove loose dust. For cleaning between the frets, especially the close higher ones, use a Q-tip with fingerboard oil. It certainly looks and feels better when the instrument is free of all the dust and dead skin particles.
4. Heat, cold & Dampness:
Even though the Zither is built sturdy, it still is made of wood, and wood is constantly on the move. It reacts to heat, dryness and dampness. It should never be in direct sun or near a heater. This could cause cracks. It should never be kept in a damp basement for extended periods; this could cause the glues to soften and joints will open up. The column on the Harp Zithers is not a carrying handle and should not even be used to remove the instrument from the case. If the Zither is not played for a longer time the strings should be loosened to a much lower pitch to reduce the full pull of the strings on the soundbox. Remember that the pull of the A 440 tuning is approximately 700 lbs. The Fingerboard tuning machines should be removed about once a year and oiled with a heavy key oil — on the worn gears you can use a good grade light grease. When installing new strings it is important to wind the string on a down angle to set pressure on the zero fret or bridge wire.
Whenever you do something to your Zither use common sense, our ask someone who you feel knows. By following these forgoing suggestions you will increase the playability life of your instrument; you will have more fun and pleasure playing and practicing and thus advance quicker to a higher playing level. The first priority of studying any musical instrument (and that applies to the Zither too) is that the instrument is in the best possible playing condition so as not to hinder your progress and enthusiasm.