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Q&As since 1989


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Customer's surface preparation prior to Anodizing

What type of surface preparation is required for Aluminum prior to delivery to an Anodizer for either Clear or a two step Black Anodization?

Thomas R. Stone
- Colton, Ca.
2000

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2000

I recommend to my customers that they remove any heavy cutting oils or coolants from the material if there was some on it. Light stuff isn't a problem, but I have honestly worked with parts where the cutting oils and things of that nature were dripping off of the parts.

This is a problem for two reasons....Its makes a real mess having that stuff dripping all over and it also makes it difficult to get a nice clean surface with which to continue operations with. I've had to clean parts like that 2 to 3 times longer than others, and even still in most cases it would not all come off the part.

Just basically use this as a general rule of thumb: If its so thick in nature that you can see it (the oils) then it probably needs to be cleaned, even partially. Some guys can handle the heavier oils, I can't and I should probably make that a note. Call your anodizer of choice and ask them what oils they can and can't handle. Our cleaner selection(s) determine the types of soils that we are capable of handling as some are better at removing buffing compounds and things similar to that, and some are better at removing oils and things such as the acids from your hands (nothing is more unattractive than a nice fingerprint on the surface of your part).

If you know what you work with, tell them, and they'll find out for you if they don't know offhand if they can handle it without many problems.

Matthew Stiltner
plating company - Toledo, Ohio

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2000

". . . nothing is more unattractive than a nice fingerprint"

I did metal finishing consulting for years, Matt, I wish I could get the operators and owners of some shops to appreciate what is so obvious to you and I. Some feel that if there is no standing customer order against fingerprints it's no problem :-)

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