Abstract: A deburring and cleaning machine and process designed to successfully clean work pieces such as castings, machined parts, and the like. The machine is characterized by a freely open work piece mounting plate movable in a predetermined pattern while simultaneously allowing free falling abrasion media to fall over, around and through the work piece. The method involves positioning a work piece in an open treating area, moving the work piece in a predetermined pattern through the treating area, and simultaneously free-falling abrasive media cascading over, around and through the work piece. The open treating area and the free-fall cascading of abrasive media provide improved cleaning and deburring of internal passageways, free falling abrasive media cascading, etc.