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Should we Stir a decorative chrome bath ?

This has been initiated after reading about stirring the Hard Chrome baths which seems to have everybody's approval to do so.

What about Decorative Chrome plating baths based on only Chromic Acid and are routinely treated with Barium Carbonate leading to precipitation of Barium Sulphate as a thick sludge which we decant and throw away once in 15 days ? We also add a proprietary catalyst which brings down burning and improves coverage and also improves the blue shade.

I don't know if this is an SRHS catalyst and if this requires to be stirred same as the Hard Chrome SRHS Catalyst, but would the same advice of stirring the bath before work be applicable to my type of Decorative Chrome bath as well or would it result in other problems if we stir up the sludge portion in order for the catalyst to function better ?

We have been conditioned to let sleeping sludges lie on account of our experience mainly in cyanide zinc baths. What is a correct procedure for startup and running of this type of a decorative chrome bath as described above ?

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

1999

Decorative or hard chrome, the supplier of the catalyst will tell you if the sludge must be stirred back into solution.

I am guessing that your catalyst is a fully soluble fluoride and probably doesn't need to be "hoed up".

Since decorative chromium plating is so thin, and the efficiency is so low, particle roughness is not a problem.

  
Tom Pullizzi
Falls Township, Pennsylvania
1999