Wire EDM Machining Overview

PMi2 specializes in all types of Wire EDM machining.

Wire EDM technology can be particularly advantageous when:

  • Materials are too hard to be machined efficiently by conventional methods: Materials such as carbide, tungsten, cermet, PCD, Molybdenum, Alnico, or hardened tool steels can difficult to machine by milling or turning due to their high hardness.
  • Materials are difficult to machine efficiently by conventional methods such as Titanium alloys or High Nickel alloys (Inconel, Hastelloy, Nickel 200, etc.)
  • Parts are prone to warping and deformation when conventionally machined. Because EDM processes can be used to machine parts in the hardened state, less deformation occurs when material is removed. Also, because the wire itself never touches the part, no stresses are induced in the surface of the material that would occur during milling or turning.
  • Thermal stability is a concern: Because the workpiece is submerged in temperature-controlled water during cutting, no significant heat is absorbed by the workpiece during the cutting process.
  • Sharp inside corner geometry is required: Because conventional round mill tooling is not used for cutting, nearly sharp inside corner geometry can be achieved. PMi2 can cut with EDM wire diameters as small as 0.004 inches, yielding inside corner radii as small as 0.002 inches.
  • Tight tolerances are required. Due to an extremely stable process, very precise equipment, and thermally stable environment, PMi2’s wire EDM equipment can machine to tolerances of +/- 0.0001 inch or better.
  • Lights-out or unattended operation is required: Because of the high level of automation on PMi2’s wire EDM machines, they are routinely operated in a lights-out condition. All of our machines are equipped with automatic wire-threading capability, so even multiple disconnected features can be machined without operator intervention.


  • Conductive material: Because the wire EDM process uses a series of tightly controlled spark pulses to vaporize material and achieve cutting, electrically conductive workpiece material is a basic requirement.
  • Features must be cut through the part: A Wire EDM machine cuts using a tensioned, electrically charged wire that passes through a pair of diamond guides. The upper and lower guides can be moved independently achieving tapered, angled, offset, and twisted profiles, but the wire must be able to pass thru the part during the cutting operation. Blind features cannot be cut using wire EDM technology.


Tensile Test Specimen Die with Wire EDM Cut Inside Profile and CNC Milled Outer Profile
Hardened Stainless Steel Fixture with Wire EDM Cut Slots
Prototype Medical Parts Wire EDM Machined from Pure Nickel
Wire EDM Machined Sharp Inside Corner Geometry in 316 Stainless Steel Part
Prototype Medical Parts Wire EDM Machined from Pure Nickel
Misc WEDM Cut Parts

Wire EDM Machine