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Yellow zinc dichromate alternative

We need to finish alternator pulleys and starters pieces we want to do the yellow zinc dichromate and silver, is there any option to do these finishes electroless or by immersion without electricity? We only need these finish to appearance any others finish colors green, blue, black, etc.?

Thanks,

Javier Real
- Mexicali, Mexico
2002

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2002

Immersion processes will not do what you want, "electro"plating is what you need. When you get to the dying of the chromate films you need to know that yellow hexavalent chromates are more difficult to dye than blue bright tri-valent chromates. Be sure to do some lab work in beakers before you charge tanks with chromates and expensive dyes. Dying chromates is not yet a pure science and the details of (1) which dye, (2) concentratrion (3) pH and (4) time need to be acertained in the lab before you pour expensive dyes into a 100 gallon tank. Let us keep in contact.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina