EDMing

Say “EDM” and most manufacturing folks think mold, tool and die work. Yet sinker, wire and hole-popping EDMs are often employed in conjunction with, or as alternatives to, traditional part-making processes, such as milling and turning. 

END USER: Prospect Mold Inc., (330) 929-3311, prospectmold.com. CHALLENGE: Reduce the time needed to cut grooves in a large mold. SOLUTION: Replace EDMing with endmilling. SOLUTION PROVIDER: OSG Tap & Die Inc., www.osgtool.com, (800) 837-2223

Better technology boosts use of EDMs for production applications.

Fine finishing with a wire EDM eliminates need for secondary operations.

The Look Ahead feature in the May 2012 issue of Cutting Tool Engineering includes a linear cylindrical drive technology for wire EDMs.

Wire EDMing requires a range of equipment and complex operations, which can lead to a variety of problems. But the capability and flexibility of the electrical adaptive control technologies that monitor the EDM process—such as flushing, wire tension, automatic wire threading, wire consumption levels, geometry control, surface quality, water resistivity level and water chiller/thermal stability—have greatly improved over the past 10 years. 

When CNC wire EDMs came on the market in the mid-’70s, feeding wire from a spool through a machine’s elaborate series of rollers and guides was a tedious manual exercise. Luckily, electrical discharge machining was an exceedingly slow process back then, so replacing wire had to be done less frequently than on today’s machines, which erode conductive metal 10 to 20 times faster than earlier models.