EDM machines make use of electrodes that are charged with electricity. The process called die sinker EDM machining is common in producing dies and molds. When a charged electrode is shaped to a specific figure, it can now burn that same figure into a metal component.

The Die Sinker EDM and Die Sinking

A die sinker EDM makes use of three-dimensional electrodes. Machining with the use of a die sinker EDM is much better as it can create the most complicated shapes, indentations and even bore holes in even hardened steel usually thought to be overlooked by the machine’s movements. A die sinker EDM makes use of a three-dimensional electrode, which then forms the required shape. With the negative energy, even the thinnest and hardest steel pieces can be processed. A die sinker EDM is also commonly known as a cavity type EDM or a volume EDM.

Die sinking occurs when one connects to a current source two metal parts that are sunken in an insulating liquid. The source of current can be switched on or off according to the controller settings. Once you switch on the current, the two metal parts produce an electric tension. One will be able to notice the sparks when there is electrical discharge and tension. As it strikes on the metal even from an inch, the metal melts as it is being heated. One after the other, sparks are produced and slowly shapes the needed figure for the metal sheet, as dictated by the electrode shape. Per second, up to a hundred thousand sparks must happen before the metal erodes. As the base metal erodes, the spark gaps go at a higher rate, and the electrodes are lowered automatically by the machine so that the process can continue. Still, about a hundred thousand sparks occur per second with the monitoring of the parameters set in the machine. These cycles, also known as on time or off time, happen automatically according to the machine’s settings as dictated by the parameters.

How Timing Of Sparks Affects Workpiece

While the die sinker EDM is going on time, it determines the time or length of the sparks that will be produced. If the on time is longer, a deeper cavity is produced in the metal sheet. This produces a rougher effect on the metal piece. The off time, on the other hand, produces less sparks as one spark is being replaced by another. With a longer off time a dielectric fluid is flushed through a nozzle in the die sinker EDM machine that cleans out the debris and avoiding short circuits. The machine can maintain settings in micro seconds. Typically, the machine can produce complex 3D shapes that can be small or odd-shaped. With this vertical, orbital and other machining cycles can be used.

Commonly, a die sinker EDM machine is used to place bits of information like names, numbers and details onto a metal piece. Once it has been cut out, the rough edges are usually made smooth.  For more information about these machines, click here.