Wire EDM

Electrical discharge machining (EDM)

EDM is a revolutionary cutting method that cuts electric lead metals regardless of its hardness. The method resembles a band saw where the saw blades equal the thread in EDM. The thread cuts the worked detail with the assistance of electric current that is lead through the thread and the material that the detail is made of. The material is worked away and becomes a result of the electric erosion that happens between the thread and the substance. During EDM the work piece is moved back and forth or sideways, the thread changes only its angle or keeps straight, depending on what type of surface the detail has. The thread is stretched with assistance of two large rolls that moves it with a steady speed ahead of or through the material that are worked.

The thread is called an electrode and it EDM-work both the top and the bottom of the material with different contours. When the thread comes in contact with the material that the detail consists of a so called “spark discharge” arises. Repeated spark discharges vaporize and melts away the material in an isolated liquid.

Over the detail a liquid is sprayed out from mouthpieces that aim at the cutting surface. During the EDM-work it is the liquid’s task to bring particles with it that are emitted from the work. The liquid is also effective in the way that it leads heat away. After its usage the liquid is brought on to a filter where it is cleaned from particles so that it can be reused.