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What type of sealant will maintain maximum hardness of hard anodize?

I have a spindle shaft that requires hard anodize coat, MIL 8625, type III, I am asking for .002" thickness, buildup & penetration, and I need to have a smooth enough surface to allow me to align my other parts within .000050" or better. I would like to have the surfaces sealed, but I still wish to have the maximum hardness possible after sealing. Is there a sealing method available that will preserve the hardness more than the normal sealing methods?

Douglas Page
product designer - Morgan Hill, California
June 14, 2010

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First of two simultaneous responses --

Wow! Most people cannot repeatedly measure a half of a tenth, let alone maintain that as a tolerance of two mating parts. You must have some of the top thousandths of one percent of certified assembly personnel.
You will have to hone the parts to get that level of measurement. There is no plating or anodizing that will come close without post treatment machining.

James Watts
- Navarre, Florida
June 15, 2010

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Second of two simultaneous responses --

Douglas

For what purpose do you wish to seal the anodize?

Willie Alexander
- Colorado Springs, Colorado
June 15, 2010

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Hydrated Aluminum Oxide IS softer than plain aluminum oxide. Do note seal. Maybe use a light oil.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

June 16, 2010