In electrical discharge machining (EDM) drilling, the workpiece is subjected to limited, highly localized heating, thus avoiding overall stress and achieving macroscopically stress-free machining. This characteristic allows it to easily cut very thin sections and fine features, which is difficult to achieve with mechanical cutting tools. EDM technology has revolutionized many aspects of toolmaking, eliminating design limitations imposed by rotating tools and enabling complex functions that were previously impossible.
Depositional discharge machining (DDM) excels particularly in creating parts with complex cavities. It can produce the complex cavities frequently required in the design of plastic and die-cast parts, with minimal impact on its value as a mold-making tool due to limitations in cavity shape. Furthermore, the "trailing wire" technique effectively prevents undercutting by the EDM, making it ideal for machining plastic molded and die-cast parts that enter the tool cavity as liquid and exit as solidified.