A machine for finishing parts, having part-isolating means such as vertical partitions or dividers, defining one or more compartments, disposed at least partially within the finishing chamber, each compartment designed to accept a part or parts to be finished and to maintain the parts isolated from each other. The finishing chamber and the part-isolating means are reciprocally movable with respect to each other first for a limited distance in a forward direction, and then for a limited distance in a rearward direction generally of the same magnitude. During movement in the forward direction the partitions are disposed intermediate the parts. At the end of the limited forward distance the partitions are removed from their positions intermediate the parts and remain in said removed positions during the rearward movement. At the end of the rearward movement for said limited distance the partitions are returned to their positions intermediate the parts and are ready to begin a succeeding cycle. Method of finishing whereby any and all of the foregoing objectives are accomplished.