Ask the Expert Question-and-Answer Archive
(Hard Chrome Plating)by Larry Zitko, ChromeTech, Inc.
June, 2003Chrome Plating Defects
Q. I'm providing you some information concerning our chrome plating issues. This has been progressively getting worse over the last 6 months.
We use SPOP 22, PS 124 maintained at 130 degrees.
Solution is checked monthly, currently checked on 01 Dec 03, composition limit is 32.9 chrome and .36 sulfates.
Rectifiers have been recently checked using PMs developed by ACE.
All bars, contacts and leads have been recently cleaned or replaced.
Anodes were removed and cleaned using scotchbrite.
Recently dummied the tank to remove trivalent chrome. 24 hour run.
We also run test panels quarterly for throw rate. Checks out okay
Here is a list of our observations of parts following plating.
Treeing still an issue
Nodules, roughness mainly at high density areas, but is not consistent on all parts even when the same part number and diameter. Plate at 3 amps per square inch.
Debonding and flaking of chrome at finish machine when taking final grind.
High percentage of rejects, guess somewhere around 65%
Platers perplexed saying chrome plating should be a fairly simply process.
All 5 platers have good experience ranging from 20 years plus down to about 10 years, plus one trainee.
Solution checks good according to our laboratory however, the solution is over (15) years old.
A. I can't solve the plating defects you have described on such critical parts from a long-distance, detached perspective. I would need both office and on-site hours for this one.
If you are interested in considering me on a consulting basis, please contact me at:
Larry Zitko
President
ChromeTech Inc.
P.O. Box 295
Windsor, OH 44099
(440) 272-5520
zitko@chrometech.com