An assembly for cleaning bone stock comprises a shell defining a void space for receiving the bone stock to be cleaned, a cutter disposed in said shell void space so that, when actuated, said cutter cleans the bone stock by removing soft tissue from the bone stock, a tumble plate having an upper surface, and a guide movable across said upper surface of said tumble plate between a disengaged position and an engaged position, wherein said guide is configured to move bone stock received in said void space toward said cutter when out of the disengaged position.
