We are very pleased to share this article, with permission, from the Conservation Studio at Yale University. Paintings Conservator, Sydney Nikolaus has documented the conservation of a half-length figure study by Edwin Austin Abbey, using the Willard multi-function table, humidification chamber and Willard heated spatulas.
The chamber reached the desired RH (70%) after approximately 30-40 minutes. The Hobo loggers were constantly monitored to make sure the chamber stayed within the appropriate RH range (70-75%). If the chamber became too humid at any point, the chamber was simply aired out by fanning the plastic sheeting (see below).
After three hours in the humidity chamber, the cracks in paint layers could be set down with heated spatulas. The PVC chamber was lifted away from the painting, and the window cut-outs were covered with Mylar to reduce air flow. The vacuum fan was switched on and the dial was set to 20% speed. Please note: the vacuum suction was not as powerful as it could have been because the entire painted surface was not covered with Mylar or thin plastic sheeting. Since the painting is unvarnished and the matte paint surface has been prone to burnishing with heated spatulas, the use of mylar or plastic interleafing was avoided during this stage. Working on top of protective interleafs of Hollytex®, raised paint cracks were carefully set down using light pressure from Willard heated spatulas (set to 70°C). Working with a colleague at opposite sides of the painting helped to flatten cracks quickly and efficiently during the limited working time post-humidification.
The painting was treated with vacuum suction. Clean plastic sheeting was stretched over the painting, and the vacuum fan was gradually increased from 20 to 40% speed. Any creases or folds in the plastic sheeting were carefully stretched out during the vacuum treatment, which lasted approximately 1 hour.
After treatment, the painting was relocated to a table prepared with a padded bed of blotter and Japanese tissue. Flattened cracks were covered overnight with Mylar-wrapped metal plates topped with gentle weights. A large piece of blotter paper was inserted underneath the metal plates to absorb any residual moisture.