Metal finishing Q&As since 1989

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Make up of chrome plating bath

I need to know the chemical make up of a chrome plating bath. I left my job a couple years ago and just recently came back to work to find that someone had discarded all of my notes on the volume/make up of CHrome baths. Then the same person today emptied the Chrome bath and doesn't know how to refill it. Also no one can figure out why there is copper appearing in the hydrochloric acid that we use for stripping.

Win Vanderstyne
Plating engineer - Rochester , New York
2004

There are two or three different chemistries. Conventional sulphate based high and low concentration (from 250 to 400 g/l chromium trioxide + 1/100 of that of sulfuric acid, rest water). Fluoride based and mixed catalyst (make-up according to vendor's instructions). What I really find amazing is to hear from a self defined "Plating engineer" that after two years away from job you need to get advise on the net. OK, you forgot, but don't you have any books or notes back home, peers, sales persons, anything? How are you going to solve future plating problems, on-line?

Guillermo Marrufo
Monterrey, NL, Mexico
2004

I hope whomever discarded the chrome plating bath knew more about properly discarding it than you seem to know about chrome plating. Seriously, how can a company perform chrome plating without records, procedures, etc. Some of these are required for a variety of regulatory authorities.

Gene Packman
process supplier - Great Neck, New York
2004

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WIN !

IF YOU WANT TO MAKE CHROME BATH , ADD WATER INTO THE TANK HALF OF THE TANK VOLUME . IF THE BATH IS DECORATIVE CHROME , ADD 35-40 OZ/GAL CHROMIUIM TRIOXIDE AND 0.14 OZ/GAL SULFURIC ACID AND ADD CATALYST AS PER VENDOR TECHNICAL DATA SHEET.MIX THE BATH VERY WELL THEN ANALYSIS THE BATH AGAIN TO READJUST THE sulphate.

Popatbhai B. Patel
electroplating consultant - Roseville, Michigan
2004