Abstract: A rotary grinding system includes a support frame and a grinding assembly coupled to the support frame for longitudinal movement, with respect to a workpiece attached to the support frame. A radial arm is suspended below the grinding assembly and rotated in a plane parallel to the workpiece. A grinding wheel traverses the radial arm, thereby working a circular, annular or sector portion of the workpiece. The height, and therefore the depth of cut, of the grinding wheel may be precisely adjusted via a single point adjustment screw or the like. Optionally, the grinding system may be controlled by a computer numeric controller (CNC) to automatically refinish programmed portions or all of the workpiece. Eccentric pins extending from the support frame and into the workpiece may be used to adjust the lateral position of the support frame, relative to the workpiece.