Often people that own bronze, zinc or other metal sculptures and other works of art, want to clean up and polish their piece at home rather than have it done by a professional. This is perfectly fine as long as the utmost care and consideration is taken. What most people do not realize is that many commercial waxes can produce an acid that can cause damage to their piece.
Generally speaking it is recommended to keep most sculptures waxed, particularly if they are displayed outdoors. Raw metal reacts with moisture, air and anything else it comes in contact with such as pollutants in the air or acids in human skin. Extreme direct sunlight can also play a big part in metal damage on outdoor pieces. The right wax provides a protective layer between the metal and damaging elements.
It is a common belief that beeswax and carnauba wax are good waxes for metals. The truth is that these waxes can actually produce acid when oxidation and hydrolysis occur and result in damage to metal and acid-sensitive materials. A best choice is a wax that is chemically neutral, free of damaging acids. One product that is used by many restoration and conservation professional is called Renaissance wax. It was created in the 1950’s in Britain under the directive of international conservationists that understood the problems caused by traditional waxes. The product that resulted removes resides, polishes, buffs to a hard finish, remains clear after multiple applications and is safe for many different materials. It is expensive but only a small amount is needed and recommended. There may be other similar products on the market, but this one is the original and has been used in numerous high-profile museums and galleries and has been recommended by highly reputable sources. Always remember to use sparingly and only work small areas at a time.
Restoration professionals often create their own waxes and this may be an additional source for the sculpture owner wanting to protect their piece. Professionals can customize a wax for a particular project by adding pigments to enhance or blend certain areas on a sculpture. Patinas are in a constant state of change and if properly maintained, the slight changes are most always on the enrichment side.
Once waxed, a metal sculpture is protected – but for how long? If it is in a very temperature and light regulated, dust-free environment it will be good for many years. If it is exposed to elements, particularly direct sunlight, ocean air or polluted air, cleaning and waxing should be repeated more often – possibly every year or even more often in some cases. The important thing is to prevent damage before it occurs and of course – using the right wax to truly protect and not cause new problems.
