Metal finishing Q&As since 1989

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Black oxide look, without the treatment

2006

We are putting together a building project where the designers have spec'd several sheets of hot rolled steel with a black oxide finish to be mounted on the wall, providing decoration. The wall these panels will be attached to is 3-4 stories high and exposed on the inside. The panels will be inside on this wall. I am not certain of the dimensions of the panels but I am assuming an inch or less thickness.

We have some issues with their choice and are looking for suitable alternatives. We need a treatment, paint, or whatever you recommend that could be touched up onsite if necessary as these panels will be installed during the final phase of renovations and minor damage to the surface in the form of scratches is possible.

We also worry that black oxide might increase the chance of rusting.

Any recommendations or alternatives would be greatly appreciated.

Jade Youngblood
DHC - Montreal, Quebec, Canada

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2006

You can touch it up with a "cold bluing" formulation. Try to visit a large local gunsmith, who will be able to show you true black oxide and the touch up forumlations. But you are right to be concerned about rust. This panel will rust if not kept well oiled or waxed, which sounds impractical.

Although it would not be cheap, black chromium plating (as on solar collectors) could look very special and can range from a smoked glass look to lamp black look.

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

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2006

Thank you for your answer.

I would like to know if there are any finishes that can be applied onsite that would roughly mimic the look of black oxide or black chromium. Oiling is not feasible for maintaining these panels as they will be going up as high as 40 feet.

Is there a paint or a stain that can be applied to hot rolled steel allowing it to have an interesting black finish that is resistant to corrosion.

If there is such a thing it would provide great versatility for maintaining the metal panels. I'll keep my fingers crossed, hoping someone knows of an adequate solution.

Jade Youngblood
- Montreal, Quebec, Canada

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Certainly paint is possible, and there are attractive paints these days with all kinds of different textures. But the ideal if possible might be make the item out of aluminum, which can be anodized black, and with fancy patterns too, and will be corrosion resistant and non-rusting.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2006

Jade, there are a number of manufacturers who produce thin gage stainless steel sheet in a great variety of colours. These sheets are also available with many choices of paterns embossed or etched into the metal. These sheets are primarily manufactured for architectural design, so they are readily available. There are also a few similar choices in aluminum.

David Fraser
- Industry, California, USA
2006

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Try mixture of tannic and phosphoric acid(2o gm tannic acid [on eBay or Amazon]/15 gm phosphoric acid/800 ml water/200 alcohol)-that is do it yourself rust converter [on eBay or Amazon] used in conservation-dark gray to black finish. Treated surface must be grease free,and it must be clearcoated..
Hope it helps and good luck.

Goran Budija
- Cerovski vrh Croatia
2006