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Chrome plating of automotive wheels

Hi I am a mechanical engineering student and am currently doing a project on chrome plating wheels. I am looking for information on how long it takes to coat every layer (copper, nickel and chromium) and what amps are used. Very rough answers are ok. Any help would be greatly appreciated.

Kevin Roberts
Student - Melbourne, Victoria, Australia
June 11, 2009

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After proper cleaning and activation the process starts with zincating. The zincate layer cannot be directly acid copper plated or nickel plated (also acidic). So the next step is either cyanide copper plating or, more likely, electroless nickel. Then copper plating, at least two layers of nickel, and chrome. For rough numbers, copper plating will be done at 30 amps/square foot, nickel at 40-50, and chrome at 150.

I think the best reference for your purposes might be the "Quality Metal Finishing Guide" to Copper. Nickel, Chrome Plating. This is a booklet of perhaps 40 pages, available from NASF.org for something like $5 to $10, which will give you suggested thicknesses. That plus any plating textbook from our "must have" book list, and you should be equipped for your project.

Based on the suggested thicknesses, Faraday's Law, and the amperages I have mentioned, you can get a good feel for how much time is required in each plating stage. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
June 18, 2009