POSITION OF A HAMMER HANDLE WHEN TUNING UPRIGHT PIANO (9-12)

[maxim_tuner]

POSITION OF A HAMMER HANDLE WHEN TUNING UPRIGHT PIANO (9-12)
Traditionally, the handle of the hammer is located to the right of (from 13 o'clock to 15 o'clock). This placement is due to the fact that most piano tuners are right-handed and find it convenient to work in this position. However, is this position justified, such as from 13 o'clock to 15 o'clock? What happens when the tuner has to press down on the hammer handle to raise the pitch? The tuning pin, according to physics, is a screw. It is securely fixed in the pinblock of upright piano. The string, which is inserted into the tuning pin, changes in pitch when an external force is applied. The string is fixed to a pinch on the frame at its lower end. So, the tuner begins to move the hammer handle from the 13 o'clock position downwards. The tuning pin starts to move clockwise in the pinblock. The stronger the tuner moves the handle from 13 o'clock, the higher the pitch becomes. But there is a catch. All modern tuning pins have a right-hand notch thread. The string is accordingly positioned to the left of the tuning pin. Thus, when the tuning pin moves in the pinblock due to the 13 o'clock movement used by most tuners worldwide, in addition to the pressure exerted by the tuner's hand trying to shift the pin from its static position in the pinblock, the most tightly stretched string at that time also applies pressure onto the pin through the hole in the pinblock. In some cases, this pressure on the pinblock hole by the string can be as much as 100 kg. Consequently, if you use this technique of moving the hammer handle (from 13 o'clock downwards), then the pinhole in the pinblock will suffer as a result of the tuning. If the lower part wood bush and, therefore, the upper part of the hole already have an ellipse on the factory's standard installation from the first day of piano operation, then using the 13 o'clock technique downwards will increase the elliptical hole and, consequently, the hole and pin will lose standard 1mm friction on leading to the inability to fix the string at the tension. In other words, the use of such a technique for the position of the hammer handle leads to, over time, from planned piano maintenance to gradual loss of the wooden resource part of the pinblock. Without realizing it, the tuner increases the natural dent in the bushing and the hole in the pinblock.

What can we do there? The hammer handle must be installed from the 9-12 positions, as Max showing here partially compensating for the string's pressure during the rotation of the tuning pin in the pinblock. In other words, the closer the handle is to 12 o'clock, the less pressure is exerted on the lower part of the bush and the upper part of the hole in the pinblock. However, you might say that this is very inconvenient for the tuner to work in this position, and indeed it is. But if you have to choose, the piano's preservation is more important than the tuner's ergonomic comfort, in my opinion.
Make your choice reasonable.
Yes, God will help you!
Good luck, regards yours, Max.
https://youtu.be/3xERvS-RPdw