White wash deposit after chrome plating

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What causes white wash deposit on wheels after chrome plating aside from low ratio of Chromic acid to Sulfate concentrations in Chrome solution?

Thank you.

Louie Rumbaugh
Lab Supervisor - Carson, California

Ed. note: Send a good photo to mooney@finishing.com if you can, Louis. Maybe what you are calling 'white wash' someone else might call haze (or maybe not).

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If by deposit you mean a salt layer, will it wash off with DI water? If it is and it has been baked on, it may take a very dilute acid to get it off.
My guess is that it is a haze or milky plate which can also be caused by the amperage either too high or too low for the tank temperature; or another catalyst that you might be using being too low.

James Watts
- Navarre, Florida

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Might we not be looking at a passive nickel problem, requiring cathodic activation in acid or cyanide prior to chrome plating.

Geoff Whitelaw
- Port Melbourne, Vic., Australia

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Try two simple fixes first -

1. Improve rinsing after nickel.

2. Let the part come to temperature for a short time after immersion in the chrome solution before applying current.

Jeffrey Holmes, CEF
- Spartanburg, SC, USA