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Anode to cathode distance for bright nickel

We are using an M&T Bright Nickel Bath and I have a question about the setup. It is a 26-gallon tank and the distance between the anodes and the cathode is 3" in each side. That is the way we bought the system, but someone told me the distance should be about 6 to 7 inches. I cannot find any documentation on this. Please help if you have an opinion on this.

Thank you

Brian Hunt
- Colorado Springs, Colorado
1996

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Hello, Brian. The first issue is that Ohm's Law pertains; the solution has resistance, and the further the parts from the anodes, the higher the required voltage will be--it's nearly a linear relationship.

The second issue is obvious: you don't want the parts to accidentally touch the anodes and cause a dead short.

The third issue is current distribution and, consequently, thickness distribution. You would like for the distance from all points on the anode to the cathode to be the same.

You haven't described all the fine details; but the fact is, in most cases it really isn't going to matter a whole lot whether the anodes are 3" away or 6-7". Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1996

If it works, don't change it. If you are trying to run very irregular parts with sharp edges, further back would probably work better. Whatever the anode can "see" will plate heavier than what it can not "see". The further back you move, the more it will tend to wrap around. The higher current density (amps/sq ft of parts) is, the more it will tend to plate the edges. 3 inches is close. I normally use 4" as a minimum, but that is just personal opinion.

James Watts
- Navarre, Florida
1996

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The distance is more important for baths with poor throwing power, like bright nickel, and less important for baths like zinc cyanide. I would make some room in your tank.

  
Tom Pullizzi
Falls Township, Pennsylvania
1996