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Buffing mark problems in finished product anodized aluminum

 

I am anodizing 6xxx grade aluminum and I am having trouble. I can see my buff marks in my final project after I dye it. I am going to try to etch it with nitric acid 60% to see if that will helps is there any other way I can get rid of these buffing marks(using brown tripoli rouge (polishing/buffing compound) [affil links] ). What do you think the best way to brighten aluminum is? Please speak English when you answer this. I'm not a chemist but I have a good understanding of anodizing.

I need my finished product to look like colored chrome(anodizing aluminum) the buffer with tripoli does a good job other than the marks it leaves. Does anyone have a bright dip or etch formula I can put together myself. Any answers would be nice (I'm anodizing decorative on 6061).

Greg Beochie
- Battle Creek, Michigan

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Durney's Electroplating Engineering Handbook [on AbeBooks or eBay or Amazon] suggests using a progressive grit before buffing. Do you use 60-80, then 120-180 before the final polish?

  
Tom Pullizzi
Falls Township, Pennsylvania
 

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If your tolerances aren't very tight, another option would be to increase your NaOH to produce a matte finish.

Marc Green
anodizer - Boise, Idaho
 

Anodizing will not improve the surface, what you give the anodizer is what you get. Insist the polisher leaves no buffing marks. 6061 has too much Copper to brighten well, use 6463 if possible.

F. Lescornez
- Plattsburgh, New York
 

I don't sand before I buff, the stuff I anodize doesn't need it, but maybe it does I'll give it a shot, and I don't want a matte finish . Are there any chemicals that can get rid of them?

Greg Beochie
- Battle Creek, Michigan, USA