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Mathematical Models for Chrome Plating Process

I will be conducting some chrome plating design of experiments (DOE). The purpose of the experiments is to construct a mathematical working model that, given some parameters such as bath temp, amps, and plating time, will predict desired chrome thickness. The desired chrome thickness range is between .004 and .006 in.

I am also very interesting in finding out the affect of distance (space) between anode to cathode (part)- using conforming anodes.

Is anyone aware of such data already being available in the industry?

Frank Gorena
aerospace - Euless, Texas
1998

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Anode spacing makes a very significant difference in plate rate. A conforming anode with 1/2" spacing will plate several times faster than one with tank anodes at say 12".

Few people talk about it, but the number of times an anode is used is a factor in plate rate.

Amps normally equals plate rate for a given bath. Not so with chrome. It is a very inefficient bath so a minor change in efficiency makes a significant difference in the plate rate. Some of the amps goes to transferring the 6 electrons that it takes to plate chrome, some goes to heat, some to the evolution of hydrogen and oxygen.

Before you waste a lot of time, I would read Cushnie (may be misspelled) and Peggars (hard chrome consultants in Cleveland) books.

Your real part and the exact way that you plate it is the only thing that counts. Lab results are at best an indication.

James Watts
- Navarre, Florida
1998

I AM INTERESTED IN CHROME PLATING ON PLASTICS AND CANNOT FIND ANY INFORMATION ON HOW TO DO IT PLEASE CAN SOMEBODY HELP ME I AM CURRENTLY CUSTOMISING A 41 TO ARTIC AND NEED TO FINISH A LONG PROJECT HELP

PAUL SCOTT
- UCKFIELD ENGLAND
1999

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I don't know what a " 41 TO ARTIC" is; I assume there was a typo. As an individual, you cannot possibly chrome plate plastic--you must have it done by a plating shop! You can't do the prep, you can't do the etching, you can't do the electroless copper, you can't do the chrome. You can't buy the chemicals because nobody will sell environmentally regulated chemicals to an unlicensed individual. You can't offer the requisite containment, you're not going to have a physician monitor your blood levels. You can't waste treat the hex chrome. Send whatever it is to a plating shop.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1999