Surface Grinding Of Copper EDM Electrodes

Even though the vast majority of copper EDM electrodes are machined by CNC machines, the surface grinding of copper is still frequently required. Many EDM machine shops are regularly required to manually grind electrodes.

One of the main reasons copper is avoided is because it is difficult to machine and it requires additional handwork after machining. This is due to the annoying burrs thrown up by machining, whether by milling or grinding.

Flood coolant is a great way to avoid the burrs, however, most manual surface grinding operations do not use flood coolant. Even a peripheral spray mist helps, but then you have the problem of a very messy operation.

How to grind copper electrodes for EDM

A very simple way to avoid this is by using any one of several wheel dressings. One of the most used dressings is paraffin, or common candle wax. You apply it manually to the grinding wheel frequently while it is turning. Just keep your fingers out of the way!

There are also commercial waxes that work well, in the same manner. One of these is the type commonly found near band saws in a tube applicator.

Another common method is to use any kerosene based oil, such as stoning oil. There is probably nothing better than kerosene to keep your grinding wheel clean. This method is a bit messier and requires more frequent applications, but it is very effective.

By simply applying one of these wheel dressings, you should be able to grind many electrodes without having to redress the surface grinding wheel.

Also, the coarser the grinding wheel, the better. For example: if you can use a 46 grit wheel instead of an 80 grit, do it! The extra spaces in the wheel structure will absorb the wax or kerosene.