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Q&As since 1989


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Flat Black Anodize without etching or blasting

I am looking for a flat black hard anodize for a machined AL frame. I really don't want to bead blast or chem etch. Any suggestions?

Keith Weech
- Chelmsford, Massachusetts
2004

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Paint!

PPG makes a DP# black epoxy primer that's tough as nails. A catalyst is added to eliminate shine.

Chris Friedberg
- Woodbridge, Virginia
2004

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Deoxidizing formulas are available which do not etch. On some alloys plain nitric acid will suffice. The matte or flat finilsh will be a function of flat-in then flater-out. If that is not flat enough then you might have to do some moderate mechanical or chemical surface modification. A very astute anodizer can juggle his temperature and current density to obtain some deposit flatness. That is about as much as we can say without actually seeing a sample of the "flatness" you desire along with the alloy and thickness of anodizing you desire.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

2004

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You want a "flat" black but no beadblast or chemical etch?

Anodizing will "flatten" the appearance somewhat, but in my opinion you can't have something for nothing. The surface needs to be made less reflective by some process before going to anodize, be it beadblast or vibratory sand etc.

Bill Grayson
- San Jose, California
2004