The working mechanism of the modern acoustic piano is made from the same materials as those used in the manufacturing of the first pianos – over 300 years ago. The main components of the action are wood and felt. Even the most famed and modern piano manufacturing facilities fully assemble the mechanism by hand. Because of its construction, the piano action is liable to be affected not only by mechanical wear and tear, but also by the ever-changing temperature and humidity levels surrounding the piano.
In order to prolong the life of the action and its optimal performance, most manufacturers recommend that the action be regulated at least once every two years. Depending on the climate and use, the schedule may be more frequent.
Piano keys are generally made of spruce, sugar pine or basswood for lightness, yet maximum strength. Spruce is normally used in high-quality pianos.
Traditionally, the sharps/flats (black keys) were made from ebony and the naturals (white keys) were covered with strips of ivory, but since ivory-yielding species are now endangered and protected by treaty, fine plastics are now almost exclusively used.
When a piano is being regulated, rebuilt, or restored there are several details that frequently are overlooked in the process. One of the first things to be noticed when approaching a piano for the first time is the way the key tops look and feel. Often you can get an idea of the condition of the rest of the piano just from your first impression at the keyboard. The keys are the pianist’s connection to the piano.
The keys must have a pleasing appearance and must feel good when your fingers touch them. There must not be too much friction, or the action will be sluggish; however, the keys must not be so loose that they wobble from side to side or make unwanted noise that would detract from the music.
Perhaps you have a vintage piano that has a number of problems with the keyboard, or perhaps the keyboard has been extensively damaged. In such a case, it is possible to replace the entire set of keys and keyframe. However this is an expensive operation costing several thousand dollars and it is usually only suitable for pianos that are undergoing complete restoration.