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Designer wants to oxidize steel for interior decoration

2003

I am a designer in Houston and I need to find out what chemicals to use to "oxidize" steel. I want to achieve the "old rusty" look...not blackened. This will be an application on panels, 22 - 29 gauge for an interior project. I would appreciate any info.

Kindly,

Tammie Turano
- Houston, Texas

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2003

There's lots of ways to do this, but a very common (and easily accessible) method is to use Muriatic acid. It's available at most big hardware stores. Muriatic acid is an old name for hydrochloric acid and it's used for things like cleaning brick masonry. Make sure you read the directions because you don't want to use this stuff full strength -- it will eat your metal plates and create a caustic cloud that is very dangerous. Water it down. Make sure you don't spray it in the air, either. This stuff is really nasty.

Color control is an art form, but basically it's tied to the amount of air, heat and the length of contact the solution has with the metal. The faster it dries, the more yellow/orange the color will be, the slower, the more red/brown. If you keep it wet (i.e., keep applying the solution) it will end up more red/brown. A thin application will end up more yellow/orange. Keep in mind that more applications will only make the thing darker, not lighter, in color. If it gets too brown, you can always sand off the rust and start over.

Be super careful and read all the directions on the side of the bottle -- good ventilation, wear rubber gloves [on eBay or Amazon], goggles [on eBay or Amazon] and all that. Acid is not to be trifled with...

If you're scared of the acid approach, you can always just use water. Put the plates out in your back yard and hose them down every once in a while. It will take a lot longer and you'll have less control over how the colors end up, but it's pretty safe and very effective.

There are lots of good book out there on patination and a lot of the concepts apply across all metals. I particularly recommend "Contemporary Patination" by Ronald D. Young.

(available on Amazon).

James Hughes
- Seattle, Washington

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Hi,

I am also interested in patinas, but more specifically on car rims. I wanted to know if the oxidation process weakens the metal. Would this treatment be safe for car rims.

Justin Vann Walden
- Jersey City, New Jersey
2004

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You might try a company named JAX .
they make numerous chemicals expressly for this purpose. By the way, Muriatic acid is diluted sulfuric acid not hydrochloric.

MARTIN COLEMAN
- New York, New York, USA
2005

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Thanks Martin. But no, muriatic acid is most definitely hydrochloric acid, not sulfuric.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005