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Anodic electroclean vs. cathodic electroclean vs. ?

Which degreasing is better? Why?

a) manual

b) anodic

c) Cathodic

d) anodic-cathodic

For Nickel on steel and copper on copper?

Kaushik Magiawala
plating shop employee - Gandhinagar, India
2007

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Hi, Kaushik. I'm not sure exactly what you mean by "manual" in this context -- but, yes, you can scrub the parts with pumice ⇦this on eBay or Amazon [affil links] and a tampico brush. This can work; in fact it's sometimes used as a test to make sure the parts are clean before plating. But it's labor intensive and subject to human error.

Anodic vs. cathodic electrocleaning is the subject of a book chapter in "Electroplating Course Manual -- Basic Practical Electroplating" and is discussed in many other plating books. In cathodic electrocleaning the work is cathodic, which means the "scrubbing bubbles" that are generated by the hydrolysis of water are hydrogen. This produces twice the gas volume of anodic electrocleaning, where the gas bubbles are oxygen, so it is more effective. However, it is not used on high strength steels because of hydrogen embrittlement, and it also has the potential of depositing metallic smuts on the parts. Cathodic cleaning followed by anodic cleaning can sometimes be best (except on high strength steel), but is a little more complex, and can be one more variable to manage. Good luck,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

My vote would go for a periodic reverse cleaning in a solution that is designed for your type metal and PR. It is the best of both worlds.

James Watts
- Navarre, Florida
2007

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March 17, 2011

Another question about electrocleaners:
What makes a cleaner anodic or cathodic since its components are the same alkaline builders, wetters, chelators, emulsifiers, etc. The condition of anionic, nonionic or cationic surfactants has to see with this? Can I operate an anodic cleaner cathodically and vice-versa on steel parts? (not PR cleaning)
This is something nobody has yet explained clearly to me. Please help.
Thanks for your valued help.

Rafael Hernández
plating shop employee - Bogota, Colombia