Your Western sculpture needs to be taken care of just like any other valuable piece of artwork. Bronze is a durable metal that usually lasts for centuries; however, it isn't immune to environmental factors that can alter its patina (color). Whether you own one piece or a collection of bronze sculptures, you must protect and maintain them, especially if they're exposed to pollutants, high humidity, or sea air. Changes resulting from environment generally occur on the surface and do not affect the integrity of the bronze. Some collectors prefer to let a sculptures' wax coatings wear thin so they can enjoy the natural bronze aging process. However, if you prefer to maintain the original surfaces of your sculpture, here are some easy and safe methods to use.

Cleaning Indoor Bronze

Display your bronze sculpture in an area away from excessive heat and humidity. When dust appears on your bronze, it is safe to use a dry, clean, soft cloth (like an old dishtowel) to wipe it away. For heavier cleaning, use a mild, unscented liquid dishwashing detergent with distilled water and a soft cloth. Clean an unobtrusive area first to make sure you haven't removed any of the surface patina. Proceed to wash the entire surface, then rinse well and dry thoroughly with a soft rag. Do not use abrasive cleansers, solvents, or chemicals to clean your sculpture without professional advice. Wax on the sculpture's surface acts as a barrier to air and humidity, both of which can cause bronze to oxidize and turn green. If it becomes necessary to re-wax your sculptures, use a clear paste wax. Some recommended brands for all patinas are Johnson’s, Trewax and Renaissance Wax. These go on easily and buff to a clean polish. To re-wax the sculpture, spread a thin, even layer of paste wax on the bronze. I like to use a toothbrush to apply the wax. Be careful not to use too much wax or work it too vigorously into the surfaces so you don't remove the original finish. Wipe off excess wax with a soft, clean cloth. Let the wax dry to a matte color (about 30 minutes) then buff with another clean cloth to bring out the luster. You can add a second coat of wax for a higher polish and added protection. If there's any white residue left on the sculpture, buff it off with a soft cloth or a soft, clean shoe brush. (Note: I find that the harder I buff the greater the shine).

If your sculpture is on a wood base, I like to use shoe polish (brown or neutral) applied to the wood. Be careful to avoid contact with the bronze. Do the same when polishing furniture or the floor under or around a bronze sculpture, as the chemicals in these polishes can damage the sculpture's patina.

Cleaning Outdoor Sculptures

When placing your outdoor piece, consider the elements that can affect the patina. These include bird droppings, dog urine, fertilizers, swimming pool chemicals, tree sap, and sprinklers. Consider the piece's exposure to corrosive moisture and humidity and place it where it will receive the least harm.
Avoid abrasive polishes, brushes, or cloths, which could scratch the metal surface.
To wash your outdoor sculpture, use the same soap with distilled water as recommended for indoor works; avoid using too much soap so there is minimal residue. Test the soap mixture in a hidden area to be certain the solution does not damage the work's patina. If it's okay, then dip a clean rag in the soapy water and wipe down the sculpture. You may need to use a small, soft brush to reach into the inner areas and crevices.
Then rinse the sculpture thoroughly with clean water to remove all soap residue and dirt. For very large works, you may need to use a hose to reach every surface. It is important to dry the piece thoroughly with soft clean cloths. Allow it to air dry for a few hours before applying a good bronze wax for protection.
When the sculpture is completely dry, use the same paste waxes recommended for indoor works. Select a soft cloth or brush to apply a thin coat of wax evenly over the surfaces during the warm part of the day to allow the wax to penetrate the pores of the sculpture. Then use a large, clean cloth or lamb's-wool pad to buff the work to a high polish.

Note: one of the tools I use to apply wax to both small and large pieces is a small propane torch. I use it to heat the bronze, which allows me to spread the wax deep into the sculpture.

If there is a fine art bronze foundry in your area, most will hire out and come do monument patina restoration for you.

If there is significant change or damage to bronze works, whether they are displayed indoors or outdoors, it's best to hire a conservator / foundry to restore the work or to give you advice on how to maintain it. Protect your investment and enjoy it for many years to come.

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