Bower-Barf is a black rust-resisting finish applied to steel and iron only and is not applicable to non-ferrous metals. It is named after two men, Mr. Bower and Mr. Barff, who originally developed the process.
Iron or steel items to be finished are heated in special furnaces to approximately 1700 degrees Fahrenheit, at which temperature they are cherry red in color. While at this temperature, live steam and volatile hydrocarbon liquids are injected in to the furnace for a period of several minutes. The chemical action of the heat, water-vapor and hydrocarbon gases on the iron and steel is such that the surface of the items being treated become oxidized and carbonized. The surface becomes covered and impregnated with a hard, non-porous, grayish-blackish coating. The surface with this treatment practically becomes impervious to moisture. After parts are removed they are dipped in a special oil and wiped off. The finish becomes a dead black and is extremely beautiful and very practical for interior use.
Current Day Finish Option:
We at Al Bar Wilmette have a colder process that is done with a non-volatile process in our shop. We refer to our finish as the ‘Olde Iron’ finish (though Bower-Barf is certainly more interesting). We use a oil, wax or acrylic for our final step of the process (depending on what the final location of the hardware/lighting will be). As with any finish we do the base metal must be extremely clean, have no surface tension, and in the case of iron or steel be finished almost immediately because of how fast surface rust occurs.