How Magnetic Filtration Can Help Eliminate Typical EDM Problems

Electrical Discharge Machining (EDM) is one of the most powerful and precise methods of cutting within the manufacturing industry, recently creating a buzz with its impressive capabilities.

With EDM machining expected to grow to be a $6 billion industry by 2027, the process is fast becoming a highly sought-after area of expertise thanks to its ability to produce intricate parts from conductive materials that would otherwise be impossible to machine. But even with its precision accuracy, and high-quality results, the process can – and often does – come with its problems.

What problems occur during the EDM process?

Secondary sparking, or re-spark, is one of the main hindrances that occur during the EDM process, resulting in a high percentage of generated energy wastage. It occurs when metal particles that have been pushed from the workplace continue to flow in the dielectric fluid. Such particles can be just microns in size; however, they can cause a spark bridge between the electrode and workpiece that ultimately slow the cutting process significantly.

How to solve typical EDM problems

By using a magnetic filter in conjunction with the traditional paper barrier filter, fluids benefit from the highest level of protection. Using a paper filter alone can allow particles smaller than the pore of the filter to flow through, leaving the fluids susceptible to secondary sparking. By introducing magnetic technology, these particles are quickly and safely removed, making sure that virtually all contamination is removed.

Eclipse Magnetics have utilised their magnetic technology, the MicroMag, to offer efficiently filtered dielectric fluid for EDM applications. With the assistance of Sodi-Tech, a global supplier and manufacturer of EDM machines, as part of its R&D programmes in conjunction with Eclipse Magnetics, ADM Precision Tools trialled the MM20 Micromag magnetic filter from Eclipse’s filtration range to explore the benefits that the filter can bring to EDM machining and the dielectric fluid.

The Micromag can filter ferrous materials such as Mild Steel, Hardened Steels, Cast Iron, Stainless Steel, Tool Steel, High Speed Steel and Tungsten Carbide etc. from dielectric fluid, removing ferrous particles, even extremely fine particle matter.

An additional benefit found due to the cleaner fluids was that there were much fewer wire breakages, making the process much more robust. As a result of the decrease in wire breakage, combined with the reduction in secondary sparking, ADM have seen a significant increase in the cutting speed of the machine, with the trial application showing improved results by between 17% and 30%.

As an example of the cost savings that the increased machine efficiency can produce, by taking the average between the increased speed results, 23.5%, and convert that into annual hours, that’s a saving of 2,000 hours a year. Using an example hourly cost of £100 an hour, that’s a £200,000-a-year cost saving. This means the MM20 Micromag unit would offer a return on investment in less than one week.

Increase Your EDM Efficiency with Eclipse Magnetics

To find out more about how Eclipse Magnetics’ products can help you streamline your EDM processes, contact us today at


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