HOME FAQs BOOKS JOBS: Help Wanted Suggestions you are here: Hotline/Forum => Letter 52084
Black Spot Problem
April 27, 2009Hello, I have a problem about electroplating: I have plated the axle wheel at my supplier but there are black spots on the surface of product especially on the shank area.
I have checked electroplating parameter and there is no problem with them but I am suspicious with rinsing water condition.
Test result shows : degreasing water rinse => TDS:521~617 ppm, pickling water rinse=>548~4710 ppm, electroplating water rinse
540~2270 ppm & chromating water rinse 513~516 ppm.
Based on the water rinse data, do you think our rinsing quality is proper enough ? is there standard quality for water rinse of electroplating.
Regards Yudi W.
Engineer - Jakarta Utara, Jakarta, Indonesia
^- Privately contact this inquirer -^
May 13, 2009
Hi, Yudi. You have not told us anything about your plating process to enable anyone to advance the alternate theory that it is a plating problem. Low quality rinse water can cause many problems, but "black spots" doesn't sound like a likely one to me. I suspect the black spots are iron contamination of the zinc plating bath. Please tell us about your plating process.
Regards,
|
 Ted Mooney, P.E. finishing.com Brick, New Jersey |