The pneumatic drill has member defining an air input and an air output and a housing defining an internal cylindrical chamber having bearing surfaces having a through axis. A driven shaft is coupled to the tool engaging chuck that defines a plurality of longitudinal slots. The driven shaft is disposed within the chamber and has a longitudinal axis offset from the through axis. A plurality of vanes each being partially formed of graphite that are individually disposed within one of the plurality's of longitudinal slots. Two of the vanes, the housing, and the driven shaft define a moving compression chamber.