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Bright silver finish after anodizing

We've been trying to get a bright silver finish after anodizing 6061-T6 aluminum. We started with a 4 min. etch and they were too gray. A 2 min. etch brightened them up slightly but not enough. Is there a way to achieve this bright silver without totally losing the benefits of the etching process?

Matt Carter
owner - Crystal Lake, Illinois, USA
2004

Etched and bright - I don't think so! The benefit of the etch process, or at least the benefit I presume you mean, is that it preps parts for anodizing as well as hides light machining marks and scratches. If you want bright then either polish parts and don't etch, or ask your plater to bright-dip the parts before anodizing. What you put in you get out.

Michael Georgiadis
engineer - Durban, South Africa
2004

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Matt,

Etching is OK but to achieve the finish you're looking for you have to go into a bright dip solution for 1 to 2 minutes then anodize. Your parts will dull up slightly if you anodize too long. On very pure alloys you can skip etch and go straight into the bright dip.

Robert Henry
Brooklyn, New York
2004