What is the pianos action and why does it need maintenance?
When you look inside your piano, you’ll find a cast iron plate or “harp” strung with steel and copper-wound strings over a large expanse of wood which is the soundboard. If you look closer, you’ll discover an intricate system of levers, springs, and hammers connected to the keyboard. The complex system which causes a hammer to strike a string when you press a key is called the piano’s action. It is a marvel of engineering composed largely of wood and wool felt. This mechanism needs to be responsive to every nuance of the pianist’s touch — from loud, thunderous chords to soft, delicate passages. We have technical drawings available for both vertical and grand piano actions. When a piano leaves the factory, each of its parts is adjusted to a tolerance of a few thousandths of an inch. This process is called action regulation. Because the wood and felt parts of the action may change dimension due to humidity and wear, the action must be serviced occasionally to maintain its responsive qua
