Summary for brite dip anodize washes off Discussion
Brite dip anodize washes off is the concern raised by Tony Adrian, who reported that red bright-dip anodized parts were losing color during a normal hospital wash cycle, while green and black non-brite anodized parts held up. The reply notes that the problem could be an improper seal, but also points to anodizing thickness as a likely factor. According to the answerer, bright-dip anodize must often be kept relatively thin to preserve its full-bright appearance, and that lower thickness may make it more vulnerable than matte anodize. The response suggests comparing coating thicknesses, since the non-brite parts may have been around 0.0005-0.0007 inches while the bright-dip parts may have been closer to 0.0002 inches. The practical takeaway is to verify sealing quality and check whether the bright-dip coating is too thin for the service environment.
April 10, 2013
Q. I have a situation where the brite dip red anodize is coming off during a typical wash cycle at a local hospital. Any ideas on what could cause this and a corrective action to prevent this from happening again? We sampled some green and black parts with a non-brite anodize and they did ok through the wash cycle.
Tony Adrian
QC Engineer – Indianapolis, IN USA
A. Hi. Although it’s possible that this batch wasn’t sealed properly, also look into the anodizing thickness. Anodizing is somewhat translucent but it’s not water clear — and what that means is that the anodizing thicknesses must be rather low to maintain a full bright look. It’s possible that your other anodizing might be 0.0005-0.0007 inches thick and your bright dip anodizing only 0.0002 inches.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com – Pine Beach, New Jersey
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April 12, 2013