I have a small chrome plating shop. I have problems when plating larger parts, such as bumpers.
I have a small chrome plating shop. I have problems when plating larger parts, such as bumpers. The center areas come out with a gray haze or a “whitewash” appearance. I do not have this problem when I plate smaller racked parts. Can you help me solve this problem? J. B.
This is a common problem and can be caused by a number of different things. Since you mention that this problem only seems to happen when plating large pieces, I would investigate whether you have the proper current density and temperature for your plating bath. Placing a large piece into the plating tank will change the current density and the temperature of the bath and may be causing the problem.
There are two excellent papers available on this subject. They can be found on www.pfonline.com/plate. In the search box type in whitewash and you will find the papers listed.
The reasons for installing an in-house cold blackening system are many and varied.
White Bronze, Copper-Tin-Zinc Tri-metal: Expanding Applications and New Developments in a Changing Landscape
This paper deals with the renewed interest in applications for white bronze tri-metal (Cu-Sn-Zn alloy).
Applications, plating solutions, brighteners, good operating practices and troubleshooting.