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Electroplating Use of Epson Salts and Sugar?

In regards to the FAQ: Electroplating--How It Works I was curious about the two added solutions as to their purposes. Is the Epson salts intended to neutralize the acid or does it have some other purpose? The sugar really surprised me. Is it to help wet the surface? Does it slow the reaction down? Lastly, could this solution be stored for an extended period of time? Any comments would be appreciated. Regards and thanks, George Gaut

George F. Gaut
Conexant - Newport Beach, CA 92660
2000

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2000

Tom Pullizzi came up with this process; I only verified it.

Nevertheless, the purpose of the epsom salt [affil links] (magnesium sulphate) is just to put a commonly available, relatively innocuous, conducticity-enhancing salt into the solution without introducing anything that contains chlorides. Table salt (sodium chloride) would be a fine conductivity enhancer, but can release chlorine gas under certain circumstances, and we were trying our best to describe a process that had the least potential of hurting anyone if kids got to fooling around in their science project.

The sugar is merely an organic intended to function as a brightening agent. Without a brightening agent, you grow large, soft, porous, crystals. The organic is drawn to the highest current density locations and clogs them, causing multiple smaller crystals to grow. Sugar is not a great brightening agent, but it's a safe one. Molasses was actually used in production plating in the old days, and we'd like to hear your results from comparing it to sugar in this experiment.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey