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Translucent dark grey anodizing on 6061 heavy plate

Client approved hand applied acid blackened (EPI INC) to linear pattern sponged grey(translucent pewter) translucent on 1" 6061-T6 plate sanded from 100 grit through 320 wet. But I cannot duplicate on large components of 11 ft table frame due to overlap at leg intersection, wetting issues due to length, overlap darkening on edges, blend issues, ad nauseum. Tried spray and wipe, sponge and terry to no avail.

Sooooo ! I went to only anodizer in the area with long tanks in Queens NY and experimented with sanding grits and patterns, etch time, anodize time and color(electro chem not dye!) and seal. However colors are too opaque.

However I want some translucency and richness of color so one (especially lay person can see it is metal not just coated "material") against the honed black granite table top(very dark charcoal grey when honed) Any immediate help much appreciated. Nobody has 12' dye tanks around metro area that I have found would therefore like to continue with current shop but all colors are too saturated even down to 3 or 4 min in color tank. My guy says less will be uneven and/or browner as that process goes from brown grey on 6061 to black depending dwell time and anodized thickness et.

I found dye tanks in RI but he'll just use black with shorter time in tank. I know Clariant makes grey dyes, etc.

I even tried some anionic wood black dye by hand but not viable must be dipped .

Norm Stavin
job shop owner - Amagansett, New York, USA
2003

Your question is not clear whether you are hard anodizer or decorative anodizer. If you are hard anodizer you can get a translucent grey with oxalic acid bath at low temp. and increased dissolved aluminum. Be sure your material 6061-T6.

Nour Mohammed
- Riyadh, Saudi Arabia
2004