When we discuss the bowhold we need to discuss the bow hand.
These joints are central to the release in the bow hand. It is quite easy to see excessive tightness in the base joints (the knuckles stick up and demand attention!). You can check your bow hand by holding a pencil like the bow. Then use the left hand to squeeze the second joint of the thumb and the third joint of the fingers. These joints must 'give' when pushed.
Different bowholds for different strokes
Firm or released
We need to understand the difference between firm and tight. We actually use many different bowholds while playing, from a very released bow hand (for example when playing tremolo) to a firmer bow hand (for example when playing sautillé, or strong détaché in the upper half). A firm bowhold allows for a high level of control over the bow while a tight bowhold means gripping the bow too much so that we begin to lose control.
Different bowholds during strokes
There is constant minor adjustment in the bowhold depending on the needs for tone and articulation. This is especially noticeable in whole-bow strokes since the bow hand can be quite different at the heel, middle and point.
Holding the screw of the bow
Often issues of tone production or clarity of articulation can be caused by problems in the bowhold. In order to focus on the actual bowstroke and not work at everything at once, try bypassing bowhold issues and experiment with holding the bow just by the screw. It is difficult to tighten or over press using this position. By taking issues in the bowhold out of the mix there can be a surprising and immediate improvement in sound and even articulation.
From the air or on the string
Both are challenges for the beginner student, although leaving the development of off-string strokes too late is a mistake. Spiccato demands a functioning bowhold with 'give' in the base knuckles.
A tight thumb can cause many problems in playing and it is often referred to in the negative: - do not grip with the thumb, your thumb is too straight, do not press. It is useful to examine the role of the thumb before beginning work on the bowhold.
The main job of the thumb is to provide counterpressure for the fingers. Try this exercise from Bayla Keyes, which shows the differences in counterpressure needed at various parts of the bow:
At the heel we can press down hard with the fingers and as the string acts as counterpressure, we can lift the thumb right off the bow.
Try exerting similar pressure as you move up the bow. You will find that the need for thumb counterpressure increases, so that at the point of the bow the thumb is fully engaged. Use only as much counterpressure as is needed. As a general rule use less in the lower half (especially the frog) and more in the upper half. Collapsing with the base knuckles or pushing the wrist down as we approach the point unnecessarily increases the need for counterpressure. In slower bows try to maintain the arch in the bow hand in the upper third of the bow, even if it means the fingers straighten somewhat.
Check the thumb leather on the bow. If the frog does not almost touch the thumb leather when the hair is loose then the leather is likely to be too far away for a secure support for the thumb.
The most powerful finger, its primary role is to provide pressure and articulation, especially in the upper half of the bow. The main contact of the 1st finger is on the top of the stick, although the first pad (near the fingernail) has a limited role in helping keeping the bow straight in certain strokes. However applying too much sideways pressure with this first pad can be counterproductive.
Release of the 1st finger
Its strength can easily be abused. Practicing without the first finger on the bow in the lower half of the bow is useful, particularly when the sound is clamped.
Traditionally, the 2nd finger sits opposite the thumb on the bow and it works with the third finger in providing the centre or fulcrum of the bow hand. These two fingers work much better in producing a strong sound if you practise regularly without the 1st finger on the bow.
The first pad of this finger has an important role in tone production. It is very useful in sautillé working with either the 1st finger or the 2nd finger.
This finger is pivotal in balancing the bow in the lower quarter of the bow or when the bow is in the air....