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A new magnesium die cast support structure for an automatic-dimming rear view automotive mirror is now being produced in a high-pressure, hot-chamber Mg die casting machine using “in-die de-gating,” two-stage ejection technology, resulting in significant cost savings.
This new magnesium production strategy is based on established miniature zinc die casting production techniques. Its successful application to larger high-pressure, hot-chamber magnesium custom die casting equipment has significantly reduced post-casting operation costs and earned CWM the 2009 “Award of Excellence” for Process Innovation from the International Magnesium Association.
In moving to a lightweight yet strong mag die casting for a new model of their advanced electrochromic mirror’s structural component, Gentex company engineers created a unique challenge for their new unit’s die design and production. They called for a new Mg tooling design to achieve the post-casting cost-savings of the high-speed miniature zinc die casting process in the 200-ton hot-chamber mag die casting machine required for the part.
Chicago White Metal, a North American pioneer in hot-chamber magnesium part design and production, brought its deep experience to bear on the project. CWM was joined by another Gentex supplier, Cast Products, who has a background in designing tooling for miniature zinc die cast parts.
The Mg die casting is now being produced without a trim die—no final trimming is required. This new application story has been featured in recent issues of Design News and Machine Design magazines.
For more details and photos on this advance in Mg die casting process technology, go to “Case Study #41.”
