Wire Changing EDM Proves Big in Micro Tooling Production

Previously, the carbide punches were cut using only 0.004 in diameter wire for both roughing and finishing the 1.750 in thick parts. Eric now runs the rough pass much faster using 0.008 in diameter wire, then the machine automatically changes to the smaller diameter wire for the finish pass.

According to Eric the EDM automatically makes wire changes in less than two minutes and has technology that allows it to know the exact center location of its V-guides. All that is required of an operator is to enter the desired wire diameter size into the machine’s control, and the guides compensate for the difference between one wire diameter and the next.

But most importantly, the machine is always aware of the wire center to maintain exact part location and size once a wire diameter change has occurred and cutting resumes. “When we first looked at the CUT 2000, we were a bit skeptical as to how well the twin-head wire changing would work,” noted Eric. “The small diameter wire we run is all GF AgieCharmilles zinc-coated steel core with high tensile strength, and the machine’s wire changer quickly and smoothly goes from that to standard larger diameter brass wire.”

The machine uses patented Universal Wire Guide technology. Two stationary 3-point V-guides – an upper and lower – are all that is required to accommodate a range of wire diameters from 0.002 in to 0.012 in. Additionally, AWC capability is paired with the machine’s Dynamic Corner Control, Wire Bending Control (for complex geometries) and Variocut, a function that automatically optimizes machining parameters.

Without its EDM technology, Scenic Tool and Stamping would have to produce tooling using other more time-consuming methods. The machine allows tooling with small cavities to be processed whole to improve quality and shorten processing time. Plus the shop can cut extremely tight inside-cavity radii with the machine’s small wire diameter capability.

In production operations, Scenic Tool produces its connectors on progressive stamping presses, one of which runs at about 1,000 spm to 1,2000 spm, and approximately 90 percent of the shop’s electrical connector stampings run reel to reel.

The raw material – typically copper, beryllium, stainless steel or brass – on coils moves through stamping tooling and the connector parts are stamped one after another. The material exits the stamping process where it is re-wound onto a reel after passing through camera inspection and quality testing. Reels are then shipped to customers or out for plating.

Customers will then run the rolled strip material into an assembly machine where stampings are cut off, and approximately 98 percent of them are then affixed into plastic housings to complete the connector assembly process. Or some stampings are cut off and layered into a plastic over molding operation.

“Our end product is stampings,” says Mike. “In this business, it’s all about providing parts that are within customer specifications at the most cost-effective price, and we accomplish this in short leadtimes by always improving our operations. For instance, in addition to the GF AgieCharmilles EDM technology, we’ve incorporated advanced software that speeds the tooling design process and have initiated modular concepts into our tooling designs.”

The company has progressed over the past 18 years to its present-day 30-employee, two-building operation, with Mike Blackwell at the helm and Eric on the floor with the machine. Since its beginnings, Scenic Tool and Stamping has never really experienced any slowdowns.

Business has grown continually, even through the challenging year of 2008. And going forward, business is expected to further increase because the company has its sights set on expanding into the medical and aerospace industries. That means the shop’s EDM capabilities, along with its extensive micro-stamping experience, will play a key role.

Scenic Tool and Stamping, Inc., 620 Melvin Hill Road Campobello, SC 29322, 864-472-0360,  scenictool.com.

Gf AgieCharmilles, 560 Bond Street, Lincolnshire, IL 60069-4224, 847-913-5300, Fax: 847-913-5340, www.us.gfac.com.