The basic process
Wire EDM, also called wire cut EDM or electrical discharge machining, cuts metal by creating controlled sparks between a wire electrode and the workpiece. The workpiece must be electrically conductive.
The wire does not mechanically push against the material in the same way as a milling cutter. This makes the process useful for fine internal profiles, narrow slots, hardened materials and parts where low cutting force is important.
When wire EDM is useful
- Parts already hardened before final cutting.
- Tool steel, carbide, stainless steel, copper, aluminium and other conductive materials.
- Intricate 2D profiles through a plate, block or insert.
- Sharp internal corners that are difficult to machine with round cutting tools.
- Components where burr control, repeatability or tight tolerance is important.
When it may not be the best option
Wire EDM is not always the cheapest or fastest process. For simple features in softer material, CNC milling, turning, laser cutting, waterjet cutting or conventional machining may be more practical.
It is also generally not suitable for plastics, ceramics or other non-conductive materials unless a different specialist process is involved.
Good information to provide
Suppliers can quote more accurately when you provide a drawing or CAD file, material grade, thickness, quantity, tolerance, finish requirements and whether secondary operations are needed.