“The Use of a Thermally Applied Wax Coating on a Large-Scale Outdoor Bronze Monument.”

ICOM-CC 12^th Triennial Meeting Preprints, Lyon, France, 1999

Author and Speaker: Joseph Sembrat

ABSTRACT

Conservation Technical Associates LLC (CTA) was awarded a contract for Phase I for the conservation of the bronze statuary groups which compose a part of the Cuyahoga County Soldiers’ and Sailors’ Monument located in Cleveland, Ohio, USA. The monument which memorializes the men who served in the United States Civil War consists of a central building with a large column rising out of the center of it. Surrounding the structure are four realistic bronze statuary groups which represent, in heroic size, the four principal branches of the military service: Infantry, Artillery, Cavalry, and the Navy. Each of the four sculptural groups measures approximately 5.8 meters wide by 2.1 meters deep with each of the individual figures measuring approximately 2.4 meters high.

The objective of the conservation treatment was to model, cast, and reattach missing bronze elements, perform superficial corrosion removal, locally patinate areas to help unify the surface coloration, and the application of a protective barrier coating of microcrystalline wax to a heated bronze surface (generally referred to as hot waxing).

Due to the highly competitive nature of the contract, it was essential for the author to research and employ cost-effective conservation practices without sacrificing the quality of the treatment. As part of this research, several different wax application techniques were designed and tested to determine their efficiency versus traditional practices. Of the many application techniques tested, it was found that a modified hotmelt system performed best. The equipment is a completely self-contained unit that was originally designed to apply  wood lamination adhesives, insulation, and bonding foam to various substrates. Since the idea of heating a solid mass of adhesive into a liquid so that it can be spray-applied is the same for the application of waxes, the author and the manufacturer of the equipment fine-tuned the system so that it could be used to apply protective barrier coatings of wax to outdoor monuments. The system proved to be superior to traditional application techniques because it allowed wax to be applied into previously inaccessible areas and was estimated that it reduced the coating application time by 50%.

Because of its self-contained features and ease of use, the hotmelt system appears to provide a considerable improvement over the technique proposed by Nicolas Veloz in his paper entitled, “Development and Implementation of a New Method of Wax Application for Outdoor Sculpture Using an Airless Sprayer” which was presented at the Objects Specialty Group session at the 1996 American Institute for Conservation of Historic and Artistic Works Annual Conference. His system required that the wax be thinned with solvents to a consistency of yogurt so that it could be transferred with an airless spray pump and pass through hoses so that it could be sprayed-applied to a heated surface. This approach poses several safety, technical, and environmental problems which are overcome by this author’s approach.