Q: What is the best type of Coated EDM Wire to use for High Precision machining applications?
A: When researching coated EDM wires online, you’ll probably come across lots of information on different types and the unique benefits of each type. But, did you know that certain types of coated wires, although fast in performance, might cause degradation to a machine’s accuracy output?
It is important to recognize the certain types of coated wires that can degrade a machine’s accuracy output. Part accuracy can be degraded with coated wire as a result of the wire’s outer coating eroding and vaporizing quicker than a standard brass wire. This deviation is often seen as a tapered error in the part from the additional wire electrode wear. Some coated wires have an outer coating that can also affect a machine’s pick-up cycle accuracy. This is either due to an oxide layer or from the flaking rougher surface of the coated wire.
Certain wires are specifically designed for high accuracy applications. These kinds of wires tend to provide less of a machining speed increase than high-speed type coated wires. One of the oldest and most common coated wire types is the Type-A Wire, which is ideal for high accuracy applications. A-Wires often have a distinctive bright and shiny silver color. They provide a minimal machining speed increase compared to brass wires, but typically provide a more reliable AWT performance whilst achieving high levels of surface finish and accuracy.
A-Wires are typically produced with a higher tolerance level than traditional plain brass wires, providing an accuracy advantage. Many machine OEM’s recommend using A-Wires, as they have been the industry’s go-to wire in achieving the highest part quality and the best possible surface finish, especially on carbide materials.
As we continue to explore best practices in using coated EDM wires, be sure to join us next week for an in-depth look at how to achieve best surface finishes.