The hair of the bow should be loosened when the bow is not being used.
Loosening the hair removes the tension from the bow and prevents the
stick from warping.
The hair of the bow should not be touched with the fingers. Fingers
leave oily deposits on the hair of the bow that prevent it from
Over time the horse hair will become stretched, dirty, and may break.
The barbs on the hair break down, and the hair will not grab the
strings very well.
A bow should be rehaired once a year, especially if it is being used
everyday. Rehairing will restore proper balance to the bow and
the fresh hair will grab the strings rosined correctly.