author, Lauren Sweet
This past month The Burghers of Calais have been kept under wraps. No, they haven’t been shrouded in secrecy, they’ve been swaddled in blankets. The Burghers of Calais, one of Auguste Rodin’s most famous collection of statues and among the premier pieces in the Stanford collection, have been in preventative protection during a nearby drainage-modification project (the old system was causing pooling).
The Outdoor Sculpture Conservation Crew first washed the statues using a mild detergent called Orvus, then rinsed and dried the bronzes with lint-free rags. The state of the protective wax coating was assessed, and the six bronze men were wrapped in heavy duty blankets (more about this process here…). Once the construction was complete, the statues were unwrapped, safe, sound, and ready to pose with their many visitors.
Authors: Lauren Sweet, Bryce Cronkite-Ratcliff, Elizabeth Saetta
Rodin’s The Gates of Hell is one of the crowning jewels of Stanford’s sculpture collection. A monumental work of this scale requires a significant conservation effort. As with all sculptures in the outdoor sculpture collection, The Gates is cared for by the conservation crew, and its condition is constantly monitored. All bronze sculptures receive an annual treatment of washing, waxing, buffing, and any other additional conservation treatment necessary, including touch-ups. This conservation work preserves the sculpture in perpetuity and heightens visitors’ experiences of it.
The Treatment: August 5th through 9th 2013
Preventative conservation treatment of The Gates of Hell is a weeklong project.The work began early on a Monday morning with a thorough washing of The Gates. The conservation crew faced many challenges: first, how to reach and wash the upper reaches of a massive sculpture nearly 20 feet tall. A 45-foot electric boom lift with an articulated arm was the answer, but this posed its own challenges, including how to maneuver the lift into a garden full of other priceless Rodin works, and how to position it in relation to the large, broad, raised pedestal that The Gates sits upon so that the arm of the lift could extend to reach the entirety of the sculpture. In areas where the lift arm could not reach, a large ladder was used.
Once these logistics were smoothed out, the cleaning could begin. An entire day was dedicated to washing The Gates. Every crevice of the sculpture had to be rinsed, washed with soft nylon brushes and a gentle detergent known as Orvus, rinsed again, and then dried. All of these steps are crucial. The first rinse helps to remove large debris or dirt accumulations on the sculpture. Interesting things were found at this stage, including several small rocks high up in the top pockets of the sculpture and a headband that must have been slung onto the roof of the piece. Soap and soft scrub brushes do what one would expect, assisting in the removal of the tougher grime, including things like bird droppings. Another unexpected discovery during the treatment was four individual wasp nests, nestled in among the twisting figures in low relief areas. Professional exterminators were called in to remove the nests so that conservation could proceed. After the final rinse, the sculpture was dried with soft towels to prevent minerals in the water from depositing on the surface through evaporation. These mineral deposits detract from the sculpture’s patina and are difficult to remove.
The next steps were wax application and buffing. The wax application is ideally done when the metal is warm, so that the wax melts and then coats the metal surface thoroughly and evenly. To get the most complete and successful application, propane torches were used in conjunction with the heat of the afternoon sun. The conservator’s tool kit included: a tinted micro-crystalline wax thinned with mineral spirits, brushes, propane torches, and nylon stockings. Once the wax was applied, the spirits evaporated, leaving only the protective, hard, solid wax layer behind. At this point the surface was thoroughly buffed, a job for which the soft, fine nylon of women’s tights is perfect. Buffing smoothes brush strokes and irregularities in the wax application, and the resulting shine reveals the detailed dimension and relief of the sculpture.
By the end of a long week, the conservation crew had washed and waxed not only The Gates of Hell, but also the statues of Adam and Eve that flank The Gates, and The Spirit of Eternal Repose that sits high atop a column nearby. The result is a cleaned, beautifully shining bronze—shielded from the elements with a protective coating so that these masterpieces may be enjoyed by generations of visitors.
Stanford’s campus and the Cantor Arts Center is fortunate to have two totem poles in our collection carved and painted by prominent totem pole artists of the Pacific North West. Boo-Qwilla by Art Thompson was installed in Dohrmann Grove in 1995 and Stanford Legacy by Don Yeomans was installed in Canfield Court in 2002. Recently these poles underwent an extensive preservation and restoration effort.
One of the most basic needs of an outdoor work of art, like Stanford’s totem poles, is preventative maintenance in order to keep the sculpture looking its best, and even more importantly to maintain its structural integrity and overall condition.
The objective of this re-painting and preservation project was to clean the poles and restore them as closely as possible to their original appearance and the artist’s intent, and, to combat factors that could contribute to their deterioration.
Before any work was considered, the artists and their estates were consulted and artists John Livingston and his wife Maxine Matilpi were chosen to carry out the re-painting of the poles. The Native American Gallery of the Cantor Arts Center of Stanford University displays several of John Livingston’s carved and painted wood artworks and a beaded textile by Maxine Matilpi. Livingston has a long-standing relationship with both of the totem poles artists. He had worked closely with Art Thompson during his career, and served as assistant carver to Don Yeomans during the creation of the Stanford Legacy pole. More information about their work can be found in these short videos of John Livingston and Maxine Matilpi in the Native American Artist Series, produced by the Quintana Galleries.
A professional conservator with an expertise in totem pole conservation was consulted before any intervention. Andrew Todd visited to inspect the poles and weigh in on the current condition of each, in order to provide treatment recommendations based on his experience treating totems and museum background. Andrew lives and works in Canada, where totem poles are abundant, and travels the world to treat totem poles in situ. For more information on his practice visit the AT Conservators website.
The first stage of the treatment was a thorough cleaning. The poles were washed with a mild detergent and soft bristle brushes to remove any dirt or bio-growth in preparation for a fresh coat of paint. Before the painting could be done an additional application of wood preservative was necessary to deter wood boring insects. Both of the totems had previously been treated in this manner, however because the preservative is water-soluble, washing the poles may have removed some of the previous application. To ensure the wood was protected a 10% solution of Timbore, a borate-based wood preservative, was applied to the poles using a garden sprayer. The application was focused on the end-grain where the wood is most absorbent, allowing capillary action to carry the solution throughout the totem pole and disperse the protection. Once the poles were clean and treated with a preservative the painting could begin.
Totem pole artists John Livingston and Maxine Matilpi traveled from Victoria, Canada to carry out this important work. Good conservation practice makes every effort to maintain a connection with living artists, and in the case of totems, Livingston and Matilpi were an essential part of the project. The intention of this project was to maintain the cultural integrity of the totem poles, while providing materials that will prolong the life of the artwork. Much effort was put into identifying paints to replace the original paint formulas, which are no longer manufactured in compliance with current California V.O.C (volatile organic compounds) laws. Livingston and Matilpi used exterior grade acrylic paints approved by each artist’s estate, which were selected based on their similarity to the original artist-applied paint and proven exterior durability.
A protective coating was applied after the painting was complete. A handmade coating developed by the US Forest Service was chosen from a variety of available wood sealants because it was developed specifically for the protective coating of totems, and has proven successful in many case studies after years of exposure to the elements. The coating was mixed just before application and applied with a hand sprayer to the surface of the poles. The coating was carefully wiped from the painted areas to avoid creating an uncharacteristically glossy surface over the matte paint, where it could not be as effectively absorbed into the wood grain as on the unpainted surface.
A few areas of Stanford Legacy required more attention after painting and coating were complete. The proper left side of the figure holding a shield had a previous repair/fill that had deteriorated. This fill was carefully removed with chisels and a hammer. A new fill was created using epoxy bulked with sawdust and tinted with dry pigments to match the surrounding wood. A few areas of delaminated and detached wood were adhered in their original positions using epoxy and clamping pressure from a nylon ratchet strap around the circumference of the pole (protecting the wood and paint from pressure and abrasion with a Mylar and cotton towel barrier).
Lastly, a new zinc cap was made to fit the top of Stanford Legacy. These types of caps are made for totem poles to protect against direct water penetration of the end-grain, and also because certain metals, such as zinc, provide ionic protection. As the zinc corrodes over time the ions released act as a biocide, preventing the growth of small organisms that can be destructive to the wood. Not too long ago Boo-Qwilla received a similar treatment and was given a lead cap because lead ions possess similar biocide properties.
Also check out Stanford News article Pacific Northwest artists restore Stanford totem poles to their original grandeur
The D-School (Institute of Design at Stanford) pride’s itself on a napkin sized manifesto, with a simple, but grand objective written in bold black letters “Create the best design school ever. Period.” The napkin goes on to list how to achieve this goal: 1. Prepare future innovators to be breakthrough thinkers and doers, 2. Use design thinking to inspire multidisciplinary teams, 3. Foster radical collaboration between students, faculty and industry and 4. Tackle big projects and use prototyping to discover new solutions.
Recently the D-School sent four students on a mission to apply their napkin manifesto to the Outdoor Sculpture Maintenance Program at the Cantor Art Center, and they were radically successful. Calder Hughes, Kristen Dobson, Michelle Daoud and Julia Jezmir shadowed Elizabeth Saetta, Outdoor Sculpture coordinator and object conservator, and the crew of students who maintain the sculptures on campus. Through observations and interviews the D-School team recognized the needs of the program and offered solutions.
The “Art Cart” is used to transport both the crew and their supplies around campus to accomplish the constant preventative maintenance required for over 100 sculptures, as well as to deal with the latest conservation treatment issues (ie. graffiti or metal corrosion). Conservation of art, including outdoor sculpture, involves specific training in not only art, but also chemistry and material science. Although the cart is functional, it does not denote the importance of the work it helps to accomplish.
What the D-School recognized was not just a problem, but an opportunity.
Currently, through economical use of space and crafty design, the cart enables the crew to get themselves and their supplies where they need to go, but the cart’s present condition doesn’t represent the specific training, or meticulous work they do. The D-School produced a prototype to meet the broader needs of outdoor sculpture conservation. The updated cart prototype offers well laid out storage space, with specific conservation equipment in mind, and even more importantly it has transformed into mobile advertisement to help the campus community better understand the significance of the task at hand, the preservation of a world class outdoor sculpture collection.
On Friday December 16th, I had the pleasure of assisting with the hyperspectral imaging of three paintings in the Cantor Arts Center’s collection, including Andre Derain’s Still Life With Fruit (1938), Dirck van Delen’s Solomon Receiving the Queen of Sheba (1642), and Hieronymus Bosch’s The Last Judgment (1500s). Joyce Farrell and Torbjorn Skauli of the Stanford Center for Image Systems Engineering led the advanced imaging procedure, which employs a high-resolution MCT (mercury cadmium telluride) detector that produces digital, high-resolution true-color renderings, performs near-infra-red scans to uncover any underdrawings, and provides information about the pigmentation and other materials in the medium. Both the Louvre and the National Gallery have also been using this system to study and photograph their collections. (See http://www.hyspex.no/pdfs/HySpex_Art_scanner_web.pdf.)
What is hyperspectral imaging? First developed for remote sensing applications, hyprspectral imaging collects information about a scene or an object from across the electromagnetic spectrum. It is is a type of spectroscopy that collects information as a set of images. Each image represents a range of the electromagnetic spectrum, known as a spectral band. Hyperspectral imaging deals with taking snapshots using narrow spectral bands over a continuous spectral range to produce a visual rendering of the spectra of all pixels in the scene. To examine art, the hyperspectral imager gleans optical information over visible (400-700nm) and near-infrared wavelength ranges (700nm to > 1micrometer), as some oils and pigments don’t fluoresce in the visible light range. Because certain objects and materials leave unique fingerprints across the electromagnetic spectrum, the imaging technique has been applied in a multitude of ways in the fields of geology, agriculture, resource management, and medicine – to image faces, large fields, forested areas, and even pig organs.
The processing of these high-resolution, spatially-resolved data sets is rather complicated. In fact, Brian Wandell and Joyce Farrell are teaching a class next quarter (http://white.stanford.edu/~brian/psy221/syllabus.html), and they hope some students from the class will be interested in analyzing the images.