Where the
world gathers for metal finishing
Q&As since 1989


-----

Copper strike problems

We are plating copper over steel sheet. Being in a third world country we are mixing our own strike solution consisting of:
Potassium Cyanide (NaCN)
copper sulphate [on eBay or Amazon](CuSO4)

When plating large pieces of sheet metal, we experience bubbles and bumps on the surface.

Is there an anti foaming or other agent that can be made from common chemicals that will control this problem?

Totok Priharsanto
- Yogyakarta, Indonesia
2002

---

Totok,

Parts are blistering from your copper strike, may be lot of the reasons, Check the part after soak and electroclean if any grease left over the part, I do not know why are you using copper sulphate chemical instead of copper cyanide? Check metal in your bath, may be too high? or drag out oil or grease in your copper strike bath during the plating process. Some non cyanide copper strike bath are available , they are using copper sulphate and other chemicals.

Popatbhai B. Patel
electroplating consultant - Roseville, Michigan
2003

I'm a chemist. I want from you how to prepare copper strike in my laboratory -- what elements do I want?

Ahmed rashed
- mansoura, Egypt
May 24, 2010

---

Hi, Ahmed. You may realize this, but maybe you don't if you are not from the electroplating industry. In the developed world, plating shops very rarely formulate their own plating or strike baths anymore; rather they purchase them from companies who formulate them to proprietary formulas.

These proprietary formulas can be based either on sodium cyanide or on copper pyrophosphate. EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser] is one source of pyrophosphate strike baths.

The Metal Finishing Guidebook and the Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon] are good sources for formulas but -- because of the increasing tendency for shops not to formulate their own baths -- older versions of these books will be more informative on home-brew than newer editions. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 27, 2010