Development of a Polishing Jig for Machining Centres

A polishing jig was designed and manufactured to enable polishing of metal surfaces on CNC machining centres, on which these surfaces are normally finish-machined first. The jig accommodates ring-type tools rotated by a high speed spindle, rendering the machining centre’s own spindle redundant. Passive control of the polishing force is materialized through the machining centre’s Z axis displacement acting on the jig’s springs. Jig design is explained laying special emphasis on calculations pertaining to the springs employed. Functionality of the jig was tested with trochoidal polishing paths and typical results are presented in terms of peak-to-valley surface roughness attained, verifying that a uniform ‘mirror range’ finish is achievable.