for molds with small batch of production and of low precision, the guide pillar can be directly fitted with pilot hole on the plate. The hole should be generally made into through hole, when the cavity plate is rather thick, if the pilot hole is a blind hole, a blowhole should be made on the side wall of the blind hole, or a vent groove can be abraded on the main body of the slide guide pillar and at the open end of the pilot hole. Length and surface roughness of the slide guiding plane on the pilot hole can be adopted in accordance with the size of guide bush of equal specification, and the diameter with exceeding length should be expanded so as to shorten the slip surface.