Blüthner Technika - Strojnica

 
 
The Wrest plank

The wrest plank takes up the tuning pins. To allow the instrument to be tuned it must be possible to turn them. The tuning pins are under the tension of the strings. To prevent their bending they pass through the iron frame where a had wood dowel is inserted which reduces the flexibility.
Of course a firm anchoring in the wrest plank is also important to ensure staying in tune for a long time. Therefore the wrest plank is made of 16 different layers of red beech in which the pins are firmly wedged.