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Removal of EDM Wire Cut Brass Residue

February 2, 2010

Hello,

Does anyone know of a effective method to remove the brass residue left from EDM wire cutting on stainless parts? Some recommend electroplishing (we've had limited success with this) others recommend nitric acid. Any information would be helpful.

Thank you

Tom Scott
medical device production supervisor - Sydney, NSW, Australia

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You should not be getting brass deposits on your part from Wire EDM.

This is not the first time I have heard of this.

The most likely cause (depending on EDM manufacturer) is that the lower head ground cables (power cables attached to your lower head) need to be cleaned or replaced. Second would be the carbide contact needs to be rotated to a non worn out area. I am saying this of the lower head because being submerged in water most of the time means more wear on it but check the upper head if this is not the cause.

This is really a matter of regular maintenance on the Wire EDM. I would also recommend you contact the service department of the manufactures agent or vendor that covers the area of the world you are at. This is not an uncommon problem when regular maintenance is not done. The brass is actually welding to the workpiece. They should be able to assist you in this matter.

Thank You

Dan Zeman
- Wood Dale, Illinois, USA
February 8, 2010

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I'm inclined to believe Dan when he says this is easily preventable, but if you still need to remove brass from stainless, I expect that a persulphate solution, or maybe a persulphate/citric acid mixture, would be effective.

Ray Kremer
Stellar Solutions, Inc.

McHenry, Illinois

February 17, 2010