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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Hard Chrome pretreatment/roughness issue
Q. I have a problem with my West line that I can't seem to pinpoint. We have dumped every bath and the line is a mirror image of the East side which is running the same chemistry and plating fine. The problem is very random. We will run a few days great and then all parts will begin to be rough toward the top of the part. They are racked vertically and the current is coming from the bottom of the part. I ran them all in manual today after they were coming out bad on the shift last night. I didn't change anything and every rack is coming out fine. Is this a chemical or electrical issue? I have sent a couple of pictures. Again the East side is running the same rinse water and racks parts the same producing good results.
Industrial Hard Chrome - Sumter, South Carolina, United States
May 27, 2011
A. The left picture sure looks like it is burned. The right picture could be the start of a burn or skip plating.
On the bad line, consider a test by putting a PVC shield around the top 5 inches of your anodes. If the part is burned, this should significantly reduce it. I will guess that your bad line tank is not getting the same agitation as the better line.
I would probably try a solvent wipe with a clean cloth to see if that made any difference.
Is anyone stirring up the "mud" on the bottom of the tank??
In any case, I would shut the line down on Friday and scoop out as much mud as you can get out.
- Navarre, Florida
June 1, 2011
A. The above picture to my knowledge seen to be disrupted current, i.e., there seems to be current interruption during plating. Please make sure that all the connections to the JOB to be plated are secure.
Best regards and good luck,
BELGAUM, KARNATAKA, INDIA
September 5, 2011
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