Wire EDM Introduction

May 5, 2024

Here is an article written by our engineering team that will provide you with background information about Wire Electrical Discharge Machining (EDM) that will help your design. EDM is a high precision cutting technology that is good especially with thick material and allows us to achieve high precision and sharp cuts.

What is Wire EDM?

Wire EDM is an electric heating manufacturing process that uses thin single-stranded metal wire and deionized water (used as an insulator of electricity), where the wire uses the heat of an electric spark to cut the metal. It’s commonly used for thick materials where the CNC end effectors can’t reach the workpiece, or the user needs very high tolerances.

How does it work

Usually, thin wires made of copper, tungsten, bronze are used to generate an electric discharge between the wire and the workpiece. When approaching a conductive material, the current jumps over. This creates sparks that land on the conductive material and erode them. Due to the unique properties of the process, wire EDM makes it easy to machine complex and precision parts made of hard conductive materials.

Wire cutting is a very accurate process. However, this is a slow process, which slows exponentially as the thickness workpiece increases. The machine has a model to generate the cutting path and the process is almost entirely automated. The resulting surface finish is excellent and allows us to create complex or delicate patterns. Non-conductive liquids or dielectrics are also used to prevent short circuits in the spark process. The waste is removed through the dielectric and the process continues.

Fig 1. Wire EDM diagram
Fig 1. Wire EDM diagram

Fig 2. Wire EDM example
Fig 2. Wire EDM example

Why/When to use Wire cutting

It has that low machine wear and therefore less machine maintenance as it’s a non-contact method. As soon as the electrode is close enough, it sparks and erodes the metal. It’s best suited to high tolerance parts, and extremely hard steels, or other tough materials like carbide or titanium.

Wire EDM is perfect for small or delicate components that require extreme care, complex shape/thick parts that require high-quality finishes.

Video Demonstration (Full Process)