A thumb piano produces a sound by the vibrations of the metal pieces. It travels into the hollowed out box through the sound hold like a piano and makes a sound. The longer the piece vibrates the longer the note is held. The thumb piano consists of different length, flat metal pieces. You can change the lengths and tune it by undoing the bar holding them down and moving the pieced back and forth to the correct tune and pitch. For the box I'll be using wooden boards I'll cut and shape for the correct size. Then i'll take some pieces of spring metal from a rake and use that as the keys. A metal bar to hold down the pieces with screws for tuning.