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  for Metal Finishing since 1989
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Hardcoat Anodizing on Aluminum with carbon fiber attached to it?

I have 2 carbon fiber bicycle crank arms that have 7075 aluminum spindles attached to them in a perpendicular arrangement. I am wondering if in this situation hardcoat anodizing can be applied to part of the 7075 spindles?

Walter Prommer
hobbyist/product designer - Kelowna, B.C., Canada
January 3, 2008

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January 4, 2008

Walter

We tried hard anodizing some 7xxx series tubes with CF on the inside. The carbon fiber conducted current and had a unique 'attack' on it's surface, particularly as the voltage increased.

We were only successful when we masked the carbon fiber.

Willie Alexander
- Colorado Springs, Colorado

It is possible that it would not be affected by the various chemicals, but I sort of doubt it. It could be masked off so the chemicals can not get to it, but that takes time and time is money. Care in the selection of the maskant is necessary to handle the various chemicals and temperatures that are encountered. Some paint on maskants can be very difficult to get off or require harsh solvents, so be very careful if you go that route.

James Watts
- Navarre, Florida
January 4, 2008

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What kind of temperature does the hardcoat process involve?

RFQ: Can anyone recommend a place that can perform this service? Thanks.

Walter Prommer
- Kelowna, BC, Canada
January 12, 2008

Ed. note: True hardcoat anodizing is done at 28 - 32 deg. F., Walter. Our advertisers will contact you in private to offer their services; or check our Jobshops Directory or your local yellow pages.