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AUTOMOTIVE COPPER ELECTRICAL CONTACT CLEANING METHOD REQUIRED

WE ARE IN THE BUSINESS OF MANUFACTURE OF AUTOMOTIVE PARTS, A FEW OF WHICH ARE MADE OF COPPER. THESE HAVE TO BE SUPPLIED IN BRIGHT CONDITION AS REQUIRED BY OUR CUSTOMERS. MOST OFTEN, OUR COMPONENTS TURN DARK IN COLOUR HOWEVER MUCH WE CLEAN IN ACIDS. PLEASE SUGGEST US A DETAILED PROCEDURE AND CHEMICALS TO BE USED TO ACHEIVE OUR GOAL OF BRIGHT SURFACE FINISH.

C.V.K.PURANIK
TRIPLE-S SPRING TECHNIC PVT.LTD. - Bangalore, INDIA
2005

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You may need to send these parts out to a plating shop for bright finishing because it may be more complicated than just an acid dip. But acid doesn't brighten copper, oxidizing agents do. You will need a nitric-acid based bright dip or a proprietary peroxide-sulfuric bright dip. And you'll need D.I. rinsing. Some shops use a final vapor degreaser treatment after or in lieu of D.I. rinsing for a spot-free finish. Unless you can package the parts immediately in a very benign shipping environment, you may need a preservative like benzotriazole ⇦this on eBay or Amazon [affil links] .

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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