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Remove scale from hot rolled steel stairs in prep for gun-bluing

March 24, 2010

My name is John Hungerford, I am a general contractor engaged in the remodel of single family residences.
We are cladding some stairs in a residence as part of a major renovation, and the client wants a blue/black finish that he saw in a design studio. We used hot rolled steel.
Is there an easy way to remove the scale from hot rolled steel? We would prefer not to use bead or sandblast, and sanding is very difficult. We need to remove the scale down to the bare metal in order to accept a chosen finish; a gun blue patina.

John Hungerford
general contractor - Westchester, California

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March 25, 2010

Hi, John. It isn't clear to me whether these stairs are in situ or are still in your shop. Bringing strong chemicals into a residence is a bad idea because these acids fume and the fumes will corrode everything. Bead blasting might be the better idea. But the steel can be pickled with muriatic acid to remove the scale. Good luck.

Regards,

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

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John,

You can use steel cleaning gel. This gel does not attack the metal surface - only heavy heat oxides will be cleaned. It is also good for welding areas.

Contact us for more information.

Anna Berkovich
Russamer Lab

Pittsburgh, Pennsylvania

March 27, 2010