During which period of an EDM cycle does the electrical spark occur?

In an Electrical Discharge Machining (EDM) cycle, the electrical spark occurs during the "On Time" period. This is the phase when the electrode and the workpiece are electrically connected, allowing a discharge of electrical energy to occur. As the spark jumps the gap between the electrode and the workpiece, it generates intense heat, which melts and vaporizes a small amount of the workpiece material, thereby facilitating the machining process.

The "On Time" is precisely calibrated to ensure efficient material removal while avoiding damage to the electrode and workpiece. Understanding this timing is crucial for optimizing the EDM process, achieving desired surface finishes, and maintaining tool integrity.