RIGIDLY SUPPORTED MOLDED PLASTICS MATERIAL PUNCH GUIDE AND STRIPPER AND METHOD OF MAKING SAME

摘要

A punch guide and stripper is molded from plastics material to the exact configuration of the punch and is supported and reinforced by a rigid punch receiving member to engage a workpiece around the slug to be punched therefrom and strip the punch from the workpiece without bulging or damaging the workpiece. The plastics material is molded in situ around the active end or nose of the punch within a rigid metal punch guide at the punch exiting end of the guide to a height or thickness sufficiently to guide and laterally support the nose of the punch throughout its stroke. The surrounding rigid punch guide prevents lateral displacement or distortion of the plastics material and terminates either flush with or just short of the workpiece engaging face of the plastics material. The active end of the punch is of smaller diameter than the main body of the punch and may have any desired configuration with a shoulder extending from the reduced section to the full diameter of the punch. The punch is projected from the surrounding guide beyond the maximum stroke of the punch thereby providing a molding chamber or cavity bounded by the nose or head of the punch, the shoulder, and the surrounding punch guide. A hardenable viscous plastics material is poured into this chamber, cured or otherwise hardened to form the stripper body, the punch is retracted, and the hardened plastics material is ground flush with or just beyond the end edge of the guide to form the workpiece engaging face. An undercut can be provided in the guide to further anchor the stripper body.