Temperature & Humidity
The influence temperature and humidity have on the bow and instrument.
The unsealed wood inside a bowed instrument and the horse hair of the bow are very susceptible to changes in atmospheric moisture and can lose or gain moisture very quickly. This has important consequences:
- Extremely dry conditions for only a short period of time (for example, in a hot car) can not only destroy the varnish but also the instrument. Glue joints, the fingerboard, the top and back, the neck etc. may come loose and worse, the Corpus can split along the grain at multiple places. Never expose your instrument to direct heat from the sun, summer and winter, even behind a window inside your home, and keep it away from heaters.
- Dryness will make wood shrink and dampness will make it swell. The soundpost may become too tight or too loose thus affecting the tone of the instrument.
- Fragile and older instruments with many repairs and thin deformed bodies are, because of their instability, especially vulnerable to such changes.
- Bow hair will become inconveniently long in damp conditions. The balance and vibrations of the bow will be affected unfavourably if the frog has moved too far near the screw of the bow. This may have an affect on your performance and tone production and it may not be possible to tension the bow properly.
- Bow hair shrinks in dry conditions and may become too tight. Although having released the tension with the screw as much as possible, the bow may still be under a small amount of tension. The bow's camber is created with heat and if the bow remains under tension, the bow will over time return to its original straight form. The bow will lose its spring and fine quality vibrations (even if a small amount of tension is left on the bow), which will have a great affect on tone production and performance ability. Have your bow rehaired without delay to preserve its qualities.