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Q&As since 1989


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Cold Black Oxide Finish on Large Steel Plate Surfaces

Q. I work for an exhibit design office, and I am looking to apply a Cold Black Oxide finish onto a large hot rolled steel plate. The plate size is 4'-0" x 8'-0 and I need to coat the entire front and back surface + all four sides. The blackened plates will be part of a permanent exhibit in a climate-controlled room in a museum.

My question(s):

-What grade of steel would provide the best results in terms of achieving an even surface finish?

-Is using a Cold Black Oxide technique cost effective versus other Black Oxide techniques? If not, does anyone have any recommendations?

-How should the steel be prepared before the Black Oxide finish is applied?

-With proper waxing and sealing after the Black Oxide finish is applied, will maintaining the surface quality still be an issue?

Michael Maggio
Exhibit Designer - New York, New York, US
2005

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Q. Hello, may I cold black oxide stainless steel too?

J.Wong
- Hong Kong
2005

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Q. Dear Ted. Can you give me some information about black chromate plating or where can find any information about it. I want to use on bolts and nuts. thank Ali Merdivan - Ýzmir Turkey 2005 A. Hi Ali. Nuts and bolts are very often zinc plated; in fact it's probably the most common finish for them. In turn, items that are zinc plated are almost always chromate conversion coated to retard white rust. The chromate can be clear, yellow, olive drab, or black. Any plating shop that does zinc plating can do black chromating, although not every shop would have a black chromating tank installed at all times. Although zinc plating can be black chromated, the alloy plating zinc-iron is even better suited to it because the iron content makes possible a stable black color without the need for silver in the chromate. Any of the plating process suppliers can direct you to an exact process for zinc or zinc-iron plating followed by black chromating. Good luck. Ted Mooney, P.E. Striving to live Aloha finishing.com - Pine Beach, New Jersey 2005

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January 9, 2015

Q. Hello,

I wonder if I can approach you with inquiry below or ask you for link to an appropriate manufacturer --

Let me ask you please for an advice regarding blackened steel use in the interior we plan for one of our projects in North Carolina.
The current design calls for ?? thick stainless steel panels with oxide-film: EPI / Electrochemical Products Inc. [a finishing.com supporting advertiser] Insta-Black SS-379 Gel applied. We are told by the CM that to achieve uniform blackened finish the steel is required to be brushed finish first and multiple application of the film to follow.
This treatment supposedly raises cost quite a bit.
So my questions: are there perhaps other ways how to achieve uniform dark, oil like finish; what is the finish durability in long term, or would it be necessary to protect the finish with a sealer to prevent wearing off; would it be possible to use gauge sheet laminated over plywood in lieu of the currently design ?? thick plate, etc.

I would appreciate any comments, advice you can provide us with.
Thank you.

George Hauner
- NY, New York,USA