The design of the mold is usually done by the molder and the mold maker. The selection of the method of gating, location of the gate, venting, parting line, and method of ejection affect the appearance and function of the part. Mold makers vary from an individual owner with several helpers to plants with hundreds of employees. The quality of the mold bears no relation to the size of the shop. In selecting a mold maker, it is important to use one who has the best type of equipment for the job and who has had experience in building similar molds. Surveys have shown that mold makers are leaving the industry about three times faster than they are being replaced. This situation has greatly increased the use of computer aided design and manufacturing (CAD/CAM) systems in mold making.
A piece may have several parting lines. Selection of the parting line is largely influenced by the shape of the piece, method of fabrication, tapers, method of ejection, type of mold, aesthetic considerations, post-molding operations, inserts, venting, wall thickness, number of cavities, and location and type of gating.
.jpg)
.jpg)
.jpg)
