ELECTRICAL DISCHARGE MACHINING (EDM)

The best materials for an EDM are those with high conductivity, such as titanium, stainless steel, and carbon steel. Materials with low conductivity are ill-suited to EDM machines.

An EDM is well-suited to machining harder materials that aren't as receptive to traditional machining methods, such as titanium. It's also better at creating complex shapes than traditional machining methods. This is because the machine relies on electricity instead of a tool that has to navigate corners or complex edges. In addition, because the machine requires no direct contact with the workpiece and vaporizes the removed material, the amount of cleaning required after the machining process is greatly reduced.

EDMs are commonly used for shaping carbide tools, as well as machining holes and slots. Their ability to machine complex shapes with little post-machining finishing required makes them well-suited for tools.

Because the machine vaporizes small amounts of material at a time, it machines at a much slower rate than a traditional cutting or grinding machine. In addition, an EDM has a hard time creating sharp edges.

A sinker EDM creates a complex electrode shape, which is then sunk into the material. The electrode removes material and creates a hollow impression of the same shape. Hole popper EDMs, meanwhile, use a rotating tube electrode to quickly create small, round holes in a piece. While both have a similar function, they differ in the complexity of the shapes they produce.