Acid Zinc Plating Brightener Q&A

A. Hi Wolfe,

Hobby plating differs from production plating in several ways.

First, you only have to please yourself, not customers who demand perfection.
So secondly, production platers need to do it right whereas hobbyists would rather spend no more money that necessary to do it "good enough".
Thirdly, production platers must maintain "equilibrium conditions" and hobbyists don't have to. By this I mean that a production plater will run a rack of parts, then another 10 minutes later, then another, and another, all day -- which demands that the condition of the bath must be the same at the end of each plating run as it was at the beginning. Hobby platers only need worry about their single part, and can make adjustments before they plate again. A simple example is that plating adds heat, and a hobbyist can simply wait until the bath cools down whereas a production plater requires solution cooling equipment.

I am not aware of any production plater in the USA who formulates their own acid zinc bath or the brighteners for it. But if you read on, you'll see at least one suggestion for brighteners from outside of the USA.

I don't know what "stainless steel plates" you used for acid cadmium plating -- maybe stainless steel inert anodes? You should use zinc anodes for acid zinc plating.

Ideally you should have anode bags, real plating tank filtration and real plating tank air agitation, but whether the aquarium bubbler that you are using will offer enough filtration to meet your standards is difficult to answer.

Luck & Regards,


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

A. Hi Jorge. The general way in which organic brighteners work is that they are attracted to the high current density areas, tending to shield them so that more plating occurs in the low current density areas for better covering & throwing power, while simultaneously discouraging growth of large crystals in favor of more & smaller, harder, and less porous deposits. This is obviously a simplification, but I don't know if anyone truly fully understands all of the chemistry going on within the boundary layer.

Here is the USA, and in many other countries, virtually no shop attempts to formulate their own brighteners from raw chemicals; rather they purchase proprietary chemistry which is the result of extensive R&D. You are certainly welcome to formulate your own brighteners, but that is the reason so little literature is available on the subject.

Luck & Regards,