In most situations, it is best to dilute this powerful acid with water. One of the fastest acting pickle is muriatic acid.

When abrasives and wire brushes are insufficient to remove extensive rust or heavy millscale, an acidic pickle can be most helpful. If the cold rolled is heavily rusted then it will more than likely need an acid pickle. Cold rolled steel just needs to usually be wire brushed followed by a wipe down with solvent. This is better than making gallons of corrosive acid solution for dipping. One way to accomplish this is to apply the pickle with a foam brush. One way to mitigate the hazards of handling acid s to use smallest volume possible. This could be hazardous due to the fumes and exposure so be sure to wear gloves and eye protection. A good and inexpensive way to accomplish this is to use an acid pickle consisting of equal volumes of water and muriatic acid. To patina hot rolled, the mill scale must come off. Hot rolled steel has a black oxide coating called mill scale. Hot rolled steel is shaped and rolled at high temperatures. There are two major kinds of mild steel, cold rolled and hot rolled steel. There is mechanical debris removal with abrasives and wire brushes, acid pickle, and solvent cleaning. To get the desired results any combination of the methods mentioned here may be needed. There are several ways to prepare the surface of steel. If you are applying any finish to steel, whether it is a patina or otherwise, proper surface preparation is paramount.

Patina solution