Oil rubbed bronze door hardware and living finishes

The corrosion resistance of bronze makes it an alloy well suited for exterior door hardware. Over time with exposure to the elements bronze develops a patina which will continue to age and become darker. This living patina is a film of oxide which develops on the surface and helps to protect the bronze substratum.

We can simulate this process by applying an acidic solution to our prepared bronze (see other posts on Birchwood M20). The acidity of the solution will rapidly darken the bronze creating a film of oxide in a matter of minutes rather months or years. However, even though the bronze has been patinaed the oxidation process will continue and the patina will continue to darken and even become verdigris in color hence the phrase “living patina”.

Can the patina be fixed so that the color of the bronze does not change?
The oxidation process can be slowed down by sealing the surface with wax or by baking on either a clear enamel of lacquer finish. The latter method is one we turn to for more commercial projects and public areas where our handles will be touched constantly.

The knob or lever of a bronze handle set will become naturally burnished in those area where it is touched to open or close a door. As the escutcheon plate typically doesn’t get touched to the same degree, this area will continue to become darker. For our more textured handle sets we simulate this effect by using different acid immersion times for the knob and plate and further accentuate this contrast be burnishing key areas like the lizard’s body shown here.