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Originally Posted by Benzwood
Hmm... several of the sellers mentioned above claim cadmium coating.
Nobody here has any experience with them as far as rust protection?
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I may stand corrected, in that platers WILL use cad plating for commercial customers, at least those that do not have any environmental requirements.
I suspect that most of the calipers you see are tin-zinc plated with a yellow chromate wash to give them a golden apparance.
I found this informative webpage about Cad plating:
http://www.findarticles.com/p/articles/mi_m0HRR/is_2000_Fall/ai_68156142
"Cadmium has had a toxic label put on it, and most of Europe, Asia and now many U.S. companies refuse to have parts coated with cadmium. Japan prohibited the use of cadmium many years ago and has done most of the research into cadmium replacements. Cadmium plating has many outstanding qualities that have been difficult to duplicate, the most important being high corrosion resistance. Contrary to the hype, cadmium plating is still easily available and is safely applied by platers.
Zinc alloys were developed to provide alternatives to cadmium plating. The zinc alloys all have many excellent features, but none of them seems to be a perfect replacement for cadmium plating. Tin-zinc alloy plating seems to be better in many aspects. Tin-zinc offers superior corrosion protection, even after the part is crimped or bent, as in the case of a threaded insert or a rivet. AVK Industrial Products, the world leader in threaded inserts, has embraced this plating finish that enables it to offer an extensive product list featuring outstanding corrosion resistance. Tin-zinc also has excellent ductility and solderability, as well as high resistance to salt and acidic environments."