cutting operation, the water supply is inadequate. To overcome this problem, increase the flow of
water until blue sparks appear.
The Servo Mechanism
Both wire and vertical EDM machines are equipped with a servo control mechanism that
automatically maintains a constant gap of about the thickness of a human hair between the
electrode and the workpiece. It is important for both machine types that there is no physical
contact between the electrode and the workpiece, otherwise arcing could damage the workpiece
and break the wire. The servomechanism advances the electrode into the workpiece as the
operation progresses and senses the work-wire spacing and controls it to maintain the proper arc
gap which is essential to a successful machining operation.
Advantages of EDM
Conventional EDM machines can be programmed for vertical machining, orbital,
vectorial, directional, helical, conical, rotational, spin and indexing machining cycles. This
versatility gives Electrical Discharge Machines many advantages over conventional machine
tools.
• Any material that is electrically conductive can be cut using the EDM process.
• Hardened workpieces can be machined eliminating the deformation caused by heat
treatment.
• X, Y, and Z axes movements allow for the programming of complex profiles using
simple electrodes.
• Complex dies sections and molds can be produced accurately, faster, and at lower costs.
• The EDM process is burr-free.
• Thin fragile sections such as webs or fins can be easily machined without deforming the
part.