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Tiny pin size pits in chrome plating

My name is Jen and my husband & I own a fabrication shop. We asked to do a job involving chrome plating. We took this job on not know anything about plating and think it would be no problem. I found a company that was recommend by several people. The parts that I sent out were flat windshield guards for motorcycles. The metal used was 18 ga steel. When I delivered them to the customer he rejected 33 out of 100. After sorting them I only found 8 that I felt were plating related, the rest he rejected due to 1-3 pin holes each part, tiny little pits that he had to mark with a marker just for us to see them. After talking to the plating company I was told that even if a thicker mil is used those tiny little pin holes with still show. Another complaint he had was if you look at the part flat you can see waves, but when it is in position of use they are hardly noticeable. Is this normal? Is my customer being to picky?

Any response would be great!

Thank you,
Jen

Jennifer Milligan
buyer - Fox Lake, IL, USA
May 10, 2009

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September 13, 2009

Hi, Jennifer.

There are no universally accepted standards (MIL, ASTM, AMS) for the aesthetics of nickel-chrome plating. It is necessary to establish a display board of what is acceptable and non-acceptable, and often this will depend on where on the part the defects are, i.e., there will often be an "A" surface and a "B" surface, with lower standards for the "B" surface.

It may be impossible to have zero gas pits on a large part, but that doesn't mean the parts are necessarily acceptable. Waviness on an "A" surface does sound like a reasonable cause for rejection, though. Good chrome plating should look like a mirror. Good luck.

Regards,

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