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-----Cracks on copper plated gravure cylinders
I work in a shop where we plate gravure cylinders.We plate all different sizes , when we plate our smaller ones over a period of time they start cracking on the ends.This is the high current area . they are also burnt on the ends. I was told this may be from organic contaminants. Is there a test to tell if you have organic contaminants in your tank ?
Vinnie Trovatometal finisher - East Longmeadow, Mass, USA
2005
The easiest way to eliminate contaminants of any kind is not to dump'em in your bath. Now, the easiest way to identify contaminants is the Hull Cell ⇦ huh? test. Of course, there are more sofisticated lab tests and recommendations to eliminate them such as dummying and filtration through activted carbon. Are you using stress reducers or levelers of any kind? Keep in mind that organics are not the only source of defects. Temperature, pH, agitation, current distribution and concentration of chemicals all have to be carefully controlled to plate successfully.
Guillermo MarrufoMonterrey, NL, Mexico
2005
If your ends are burning, you are plating at too high a current density for your bath chemistry. Putting a generous radius on the ends of your rolls will significantly decrease the high current density in that very localized area. Alternative is to turn down the amperage and plate slower on the smaller rolls.
James Watts- Navarre, Florida
2005
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