We've attempted to cover the most important aspects of viol care in this minimanual. If a problem/question is not addressed here, ask a teacher or a luthier (maker/repairer of stringed instruments) Remember--a viol that's in good shape is easiest to play.
PARTS OF THE VIOL
The parts of the viol and bow are known by special terms. You'll need to know certain things about certain parts to take good care of your viol.
Pegs. Experience will teach you exactly what kind of pressure to apply to make pegs stay where you want when you're tuning. If a peg keeps sticking or slipping, take the string off, take the peg out, apply peg dope (available in a lipstick-like case at most music stores) to the two shiny circles where the peg contacts the pegbox, and then replace both peg and string.
Nut. Rubbing a soft pencil in the grooves of the nut may help strings move more smoothly when tuning. (Loosen the strings slightly and take them out of their grooves first!)
Strings. The lower strings on a viol may last for years, but the upper ones, especially the thin top string, tend to break and will often have to be replaced. That's a fairly simple operation that you should try to master. You should also change strings when they become hairy or frayed. It's a good idea to keep extras on hand.
Frets. It's fine to move frets to facilitate tuning. If a fret eventually loosens, don't worry; that's common. The best "quick fix" is to slip a matchstick or small folded slip of paper between the fret and the neck. A broken fret must be replaced. You can use an old string of the correct weight or new gut or nylon to tie a new one. WARNING: Until you've replaced a few frets under supervision, it's best to have an experienced person do it for you.
Bridge. The normal stress of tightening strings and playing tends to tilt bridges forward, which affects the viol's sound and tuning. Check the bridge regularly to make sure it's straight; the back should be perpendicular to the belly and the feet should fit the belly perfectly. You can straighten a tilted bridge yourself. This is British gambist Alison Crum's advice: Hold the viol firmly between the knees and, using both hands, grasp the top of the bridge between thumb and fingers. Carefully shift the bridge back to a vertical position. (Some people loosen the strings slightly first.) WARNING: Get someone else to do this if you're at all nervous about it. If the bridge falls, it can damage the instrument and/or bring down the soundpost.
Soundpost. The soundpost is a stick of wood wedged precisely between back and belly inside the instrument. It is crucial to the viol's resonance, and moving it changes the instrument's sound considerably for better or worse. An instrument with a fallen soundpost is unplayable. Only a luthier should adjust or reset the soundpost.
Tightening the bow. Every time you play, you must tighten the bow hair by turning the button clockwise a few times until there's considerable tension on the stick. The correct amount will vary from bow to bow; ask an experienced player if you're not sure how tight yours should be. Always loosen the hair when you're done playing.
Rosin. This product of pine tree sap is rubbed on the bow almost every time you play. One good technique is to "bow" the rosin as if you were playing a string. Make sure you get enough rosin near the tip and on the near side of the hair. The brand of rosin is not very critical, although slightly stickier types tend to work better on bass viols.
Rehairing. Bow hair wears out and becomes slick. If you think your bow needs rehairing, bring your bow to a bow maker or luthier.
THE RIGHT ENVIRONMENT
Sunlight and temperature. Never expose the viol to direct sunlight, draughts, or extremes of temperature, which can damage the varnish and crack the wood. Be wary of transporting a viol by car in the heat of summer or cold of winter. (And as a general rule, never leave a viol in a car!)
Humidity. The ideal humidity level for a viol is 40% to 50%. Dryness not only is harmful to the instrument, causing cracks and separations, but also makes it harder to play. The response on an overly dry viol is terrible and the sound is tight and raspy. Dryness is essentially a winter problem, because humidity is high in summer. Winter is double trouble: Cold weather itself is drying, and winter heating makes rooms dangerously dry
You can check room humidity with a hygrometer, sold in many music and gadget stores. Dampits, described below, also come with a primitive humidity gauge. If you find that the humidity in your home is very low, you probably should get a humidifier--and keep it running near your viol as long as the heat stays on. (Bionaire, Vortex, and Hunter are reliable brands.)
An alternative to a humidifier is a Dampit, a sponge-filled rubber tube that is moistened under the faucet and inserted into one soundhole (usually on the bass side). It must be remoistened every day or so. Its use is also recommended if you take the viol out on a cold day. Dampits can be bought at many music stores. Use cello-size for bass, viola for tenor, and violin for treble. WARNING: Make sure the outside of the Dampit is completely dry before you insert it. Water inside the viol can cause long-term problems.
The case. Always fully lock the viol case before you pick it up. And don't store the viol with the case upright--it's too tippable.