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Coloring aluminum

 

Sir,

We are manufacturer of piston, I want to color aluminium in any color except silver.

Thanx.

Muhammd Idrees
- Pakistan

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And your question is?

Marc Green
anodizer - Boise, Idaho
 

Hi sir,

I want to change the original color of aluminium metal (piston) what I should do . . . what composition of chemical should be used to change the color of Al. please tell me the most inexpensive way of coloring Aluminium . . . We are a manufacturer of Pistons.....

Take Care,

Idrees Aziz
- Lahore, Pakistan
 

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Most inexpensive way to color aluminum:

Direct chemical coloring:

Brown to black color:
potassium permanganate [on eBay or Amazon].......10 gm
copper nitrate [affil links]...............25 gm
nitric acid(38 Be)...........4 gm
water........................1 lit
Hot immersion(80-100 C)!5 min=light brown,15 min =dark brown,30 min=black Golden yellow color: potassium permanganate......20 gm.water 1lit Hot immersion(8o C)!You can add 5 gm copper sulphate [on eBay or Amazon]for bronze color!

Red color:
potassium sulfide.......25 gm
o,3 gm potassium bichromate
alizarine................ 1 gm
water....................1 lit

Good luck! Only thoroughly degreased objects can be colored!

Goran Budija
- Zagreb;Croatia

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Hi there !
Could anyone of you tell me how to color aluminium in blue, both light and dark ? (The cheapest way, of course)
I am involved with motorcycle tuning parts.

Thanks in advance.

Oscar

oscar rivero
backyard mechanic - lagomar,canelones, uruguay
May 26, 2009

Hi, Oscar. To color aluminum for decorative outdoor application is a different thing than just trying to temporarily mark it for in-factory identification. You need to have a full polishing, cleaning, desmutting, anodizing, dyeing, and sealing process applied to these parts.

Talk to a local anodizing shop and they will explain, and maybe show you, what is involved. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
May 26, 2009