Producing a top quality die cast component part starts with a solid and well thought out design. The goal of any die cast design is to create a casting that will maximize the function of the part, while being one that can be produced fairly quickly, efficiently, with few defects, and little to no secondary operations necessary.
There are many factors that need to be taken into consideration when designing a die, such as:
• Wall thickness
• Wall thickness uniformity
• Draft
• Pockets
• Fillets and corners
• Ribs and bosses
• And more
Wall thickness
Wall thickness is the distance between two parallel (or nearly parallel) surfaces and will vary depending on the thickness-to-length ratio of the entire part. If your part is very long it is difficult to maintain a very thin wall. You want your wall thickness to be as thin as possible while maintaining the strength and overall functional requirements necessary for your specific application.
Typical minimum wall thickness:
Wall thickness uniformity
Ideally, you want a design that creates uniform wall thickness all around the casting. This doesn’t mean that it needs to be 100% the same on all sides, only that you should strive to minimize drastic wall thickness variations. Dramatic variations in wall thickness can result in different rates of cooling along the cast wall which can alter the dimensions of the finished part. Uniform thickness also allows you to better control the flow of the metal into the die in order to ensure a complete fill.
Draft
When it comes to die casting a draft refers to the slope or taper that run in the direction of the die’s opening. The taper should be greater on the interior of the die walls than it is on the exterior walls so that when the alloy cools and solidifies it will shrink and fit more tightly on the inside of the casting. The greater the interior draft, the easier the finished part will be to remove from the die and the more precise the finished product will be.
Pockets
If your part needs to be light, pockets are excellent inclusions in die cast designs. Basically these pockets, also referred to as metal savers, are open spaces or holes placed in the design of the die. Strategically placed pockets make your final part lighter without compromising any of the structural integrity.
Fillets and corners
Fillets are the curved parts of the casting where two surfaces would normally have come together at a sharp angle. They are added to a die casting to eliminate hard edges and corners that are not desired in the final part. It is best to utilize large inner and outer corner radii for the cast part. The larger the radii the stronger the final part will be.
Ribs and bosses
Bosses generally serve as stand-offs and mounting points, while ribs are added to provide support without increasing wall thickness. If it is possible, design any necessary ribs and bosses directly into the die cast. These features help eliminate sharp corners and help increase the overall strength of the finished part.
Consulting with an experienced die caster during the design phase will help eliminate any potential problems affecting tooling and production of your new part.
How can A&B help?
A&B Die Casting leads the industry with a trusted worldwide reputation for unique economical approaches and value-added services for all of your die casting solutions. We pride ourselves on doing the hard work upfront so that we can generate the most value to our customers for years to come.
Need assistance or want to get started on your next die cast project? Contact A&B Die Casting today!