Case Study: TerBeek Molding & Tool

TerBeek Molding & Tool Achieves Tight Tolerances, High Accuracy and Superior Surface Finishes with Mitsubishi EDMs and Roku-Roku VMCs

TerBeek Molding & Tool designs and manufactures high-precision plastic injection molds using three Mitsubishi sinker EDMs, one Mitsubishi wire EDM and two Roku-Roku high-speed vertical machining centers (VMCs).

A new 22,000-square-foot climate-controlled facility in Peachtree City, Ga. houses the company’s team of 20 employees.

A key customer base is medical companies requiring tight-tolerance molds, said John TerBeek, a mechanical engineer who co-owns the company with his father Brian. The elder TerBeek founded the family-run business in 2005.

Mitsubishi Wire and Sinker EDMs
The Mitsubishi sinker EDMs (two EA8 Advance Sinker EDMs; one EA8PS Advance Sinker EDM) are used for burning inserts used in injection molding tools. TerBeek Molding & Tool uses only TTK-4 graphite, a highly machinable material that is ideal for complex and difficult shapes.

The wire EDM (Mitsubishi MV1200R) is used to cut ejector/core pin holes in molding inserts and contours and tapers for stamping dies.

“Mitsubishi EDMs help us achieve tight tolerances with their stable construction and control,” John TerBeek said. “We have had very few control issues through the years and machine reliability has been superb. They allow us to pinpoint surface finish as well as electrode position throughout the machining process.”

Because Mitsubishi wire and sinker EDMs have the same graphical user interface, switching between machines is easy, he said.
“Operators that have been trained on sinker EDMs are able to switch to wire EDM machines with very little additional training, which can be done on site or over the phone with MC Machinery technicians,” he said.

Roku-Roku High-Speed VMCs
TerBeek said its two Roku-Roku high-speed VMCs are primarily used for graphite and copper electrode machining, finish hard milling and fine-detail engraving.

“The kinematics of the Roku-Roku VMCs allow us to run faster feed rates and not sacrifice surface finish or accuracy,” TerBeek said. “The machines are efficient in terms of increased cutter life, reliable Fanuc control and overall machine stability. We can run longer intervals on downstream inspection on parts that the Roku-Rokus machined.”

Service and Support
MC Machinery service and support have been exceptional the “very few times” assistance has been needed, TerBeek said.

“I can only recall one time where a 14-year-old machine was down because of a failed axis drive,” he said. “MC Machinery was able to diagnose the issue over the phone and had the replacement part here within two days.”

When the machines were moved from the old location to the new facility, MC Machinery technicians went on site to set up and inspect the new machines, with production up and running in less than two weeks, he said.