One of CWM’s Sales Engineers coined, ‘Start with the finish in mind.’ This is because the specific design features of a die-cast part almost always directly impact achieving the required surface finish specifications. For this reason, all die casting finishing requirements should be discussed with the die caster early in the design phase.
Die castings and subsequent surface finishes have a symbiotic relationship. That is, the results of each process “work together,” and each benefits from the relationship. For example, aluminum die castings that require a cosmetic surface will require attention to the location of the casting’s parting line, gate, overflows, and vents. If these design features interfere with or blemish any part’s designated cosmetic surfaces, undesired results will occur.
The tool design also exemplifies the importance of reviewing the finish with the die caster early in the project. Cosmetic surface requirements for custom die casting may require special finishing of the die cavities. In addition, the cover die half will generally be used to produce a specified cosmetic surface. This permits the ejector die half to contain the required ejector pins— which assist in ejecting the part cleanly from the die.
The die caster must understand how parts mate with other components in the final product assembly. The die caster will analyze the design to ensure a quality finish and, equally important, to make sure that tolerance specifications will be met. If omitted, this step could lead to additional finishing processes that increase piece price costs.
Cost is certainly another driver for having an early discussion with the potential die cast supplier. As discussed earlier, the geometry of the design’s features directly impacts the final surface finish. An early review with the die caster can result in minor modifications (e.g., critical surfaces, edges, and mounting features) that reduce the need for surface preparation before the final coating. The result is increased efficiency, which directly impacts lowering the final production cost.
CWM is a full-service, die-cast-to-finish supplier, unlike many die-casters that only produce raw castings. Over 90% of our castings include additional post-cast finishing operations before shipment to our customers. With that high volume of post-finishing experience and over 75 years of performance, our die cast finishing expertise is unsurpassed. Further, CWM is uniquely positioned to provide unbiased information when recommending suitable alloys with optimal finishing processes since we work with the most widely used metals: aluminum, magnesium, and zinc. If you want to tap in to that experience by reviewing your project with a CWM Sales Engineer, please call us at 630-595-4424.
