Die casting is a very versatile method used to manufacture non-ferrous metal parts in high volume. This process makes parts by injecting molten metal into a die. The molten metal is injected under high pressure and speed. One of the biggest advantages of die casting method is that it allows to make complex parts very effectively.
It can be tricky to design products for die casting. This is particularly true for housing designs, as it has mechanical and aesthetics requirements. Thin wall enclosures can be very difficult to attain and will need bosses and ribs on the inside to offer strength. The die cast product design can affect the total manufacturing costs. However, if the design is optimized for mass production, there can be rewarding results. Some of the basic points to consider in die casting product design are discussed below.
Undercut
Die casting makes parts by injecting molten metal to die under high pressure. After solidification of the molten metal, the two halves of the die will open to eject the part out. It is very important not to have any undercut areas in the opening direction of dies. This is why it is crucial to determine the orientation of the die cast component before fabrication of the die or tooling.
As the die cast components become more complex, many features will be added on the edges of the component and these features many have undercuts. So sliding cores will be added to the die casting tooling design.
Draft Angle
It is the slope or taper that is offered to the sidewalls of the die cast part. These surfaces can be easily recognized by the opening direction of the die and the opening direction of any sliding cores. Offering draft angles will enable the castings to be ejected easily from the die. Adding drafts can decrease the tendency of the parts to stick to the die, thereby improving the surface quality and cycle time.
Parting Line
The parting line is where the two halves of the dies meet and all die cast components will have a parting line. This will be noted on the part drawing as P/L or Parting Line. The best practice is to have dimensions with tolerances that relate to one side of the die, either the cover half or the ejector half, as it will be much difficult to control tolerances across the parting line.