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Causes of arcing from plating (zinc and yellow dichromate)

I need a technical explanation of what causes arcing during plating. These are extension springs, approx. .625" in length and arcing was present during the zinc & yellow dichromate process. This is a rare occurrence.

Linda Wood
Spring manufacturer - Mississauga, Ontario, Canada
2004

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I'm not sure what you are asking, Ms. Wood. I have seen arcing at the tank saddles (cathode contact points) when putting a rack of parts into the tank, or removing them. I have seen arcing under solution in hard anodizing, on rare occasion, when the voltage is very high but the anodic film has broken down for some reason. But I'm not sure that either of these is what you are talking about. Can you explain your problem in different terms?

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2004

The plater also called this condition sparking. The plater is also looking for a technical explanation for this condition. He said springs get hung up on the danglers and when the electricity is applied, sometimes there are sparks and this causes the springs to break wherever they are hit by the sparks. He said there is an uneven distribution of the electrical charge.

Linda Wood
Spring Manufacturing - Mississauga, Ontario, Canada
2004