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Ted Mooney, P.E. RET
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How to polish copper
Q. What is the best method for polishing copper?
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Abdo Akila
plating shop employee - Cairo, Egypt
December 28, 2008
? Hi, Abdo. I think people wanr to help you, but your question is too vague; we don't know if you are talking about one part or millions, pinhead size or a skyscraper, etc. Please tell us the details of your situation. Thanks!
Regards,
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
December 29, 2008
Q. My company work on electrical control panel using copper bars as conductors with dimensions (10 cm*10 mm*3 m), (12 cm*12 mm*3 m),(20 mm*5 mm*2 m) and like this.
My current method to copper polishing and treatment is dipping in nitric acid 15-20% till 5 minute then passivated with chromic acid (rinse stage with chrome) then rinse with current water
I know that this very old method
Copper is very sensitive metal so we want to know the best method for polishing copper with high brightness.
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Abdo Akila [returning]
plating shop employee - Cairo, Egypt
December 31, 2008
A. Two suggestions to look into: use sulfuric acid plus hydrogen peroxide for the brightening instead of nitric acid; use benzotriazole ⇦ this on eBay or Amazon [affil links] as the tarnish preventer instead of chromic acid. I can't promise that both or either of these will be an improvement, but they are more modern and are worth looking into. Good luck!
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
January 7, 2009
Q. I am very thankful to you.
I have another question:
After polishing copper bars there are some contact sites along the bar, i.e., if I have bar of length 2 m and this bar has 4 contact sites which used to contact the bar with other bars, how can I isolate this bar except at the contact site to plate this site by tin or silver (cost reduction), then after plating remove this isolation?
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Abdo Akila [returning]
plating shop employee - Cairo, Egypt
January 17, 2009
A. Hi. If it's just the ends, you can dip the pieces vertically, just enough to plate the ends (you may want a strip of platers tape or resist beyond the point you want to plate for a clean edge/boundary.) If you need to plate a spot in the middle, your only choices may be to either brush plate instead of tank plate, or to mask/tape everything else. But in masking/taping 'everything else', it might be possible to have a reusable PVC sleeve that you can place over most of the bar and just tape the ends of the sleeve.
Luck & Regards,
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q. I think that citric acid ⇦ this on eBay or Amazon [affil links] is the best on of tarnish preventer. What is your opinion?
Monto CarloPlating shop employee - Cairo, Egypt
January 14, 2009
A. Hi Monto. I'm sure that sodium benzotriazole is a more effective tarnish preventer for copper.
Luck & Regards,
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Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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