Shops that decide to expand into new markets are often spurred to add new machining equipment or adopt new machining processes to support their efforts. In True Die’s case, the strides it has taken to diversify its product offerings by manufacturing precise round tooling for deep-draw sheet-metal-forming applications has led it to develop an effective strategy for hard turning. The goal was to eliminate the need for inner diameter (ID) and outer diameter (OD) grinding of (primarily) hardened powder metal round tooling ranging to 64 HRC, enabling it to achieve higher material removal rates while matching what grinding could achieve in terms of concentricity, surface finish and dimensional accuracy. That it has since done, establishing the capability to hard-turn diameters and radii to ±0.0002-inch accuracy.
In fact, two of the Zeeland, Michigan shop’s recent machine additions are turning centers that were purchased primarily for hard turning. Mitch Stahl is True Die’s technical specialist who, along with Chris McCleary, turning coordinator, led a team of machinists in establishing the shop’s hard-turning strategy. In short, he says the shop’s approach boils down to three interconnected concepts: establishing overall process rigidity, implementing the right types of cutting tools and applying the appropriate cut data.
The key word here is interconnected. Mr. Stahl maintains that implementing only one or two of these concepts would not work; all must be appropriately addressed for effective hard turning. “It is also just as important to mind the small details when putting a process such as this in place,” he notes.
Round Tooling Opportunities
True Die, formerly Contour Tool and Engineering before it acquired that company in 2015, has expertise in designing, machining and assembling plastic injection molds and progressive die sets. It has a diverse array of machining equipment in its 10,000-square-foot facility, including CNC mills, turning centers, grinding machines, and wire and sinker EDM equipment.
Brian Brown, True Die’s president, says the deep-draw metal-forming industry represented an opportunity for the shop to diversify into a new market that complements the others it serves. “Our expertise of the application of deep-drawn stamping positioned us uniquely as a tooling supplier, enabling us to bring tangible solutions and higher performing tools to the market,” Mr. Brown says. “With well over 100 years of combined experience in the design, development and production of drawn stampings, we were well prepared with a thorough understanding of the unique requirements of that industry.”