The delicate operation of protecting the surface of the Volto Santo in the first months of the project. This section documents the most important stages of restoration through a combination of photographs and brief descriptions.
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Photographic documentation taken before the restoration demonstrates a number of places where the sculpture’s paint has been lost. Some of these losses reveal a preparatory layer of linen cloth ¹ applied over the wood, intended to prevent the layers of polychromy ² from being damaged by the small movements and distortions of the wood over time.
1 Medieval artists understood that wood moved and cracked over time, and adhered strips and patches of textile or fiber to the wood surface prior to painting to protect the delicate paint layers from flaking. We understand today that the movement of wood is in response to the absorption and desorption of moisture from the air, causing the wood cells to expand and contract. Paint layers are less flexible than wood and will develop cracks and even flake off if the wood movement is strong enough.
2 “Polychromy” means “many colors” and refers to the layers of preparatory grounds, paint, metal leaf, and other materials used to decorate wooden sculpture.
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Constructing a scaffolding in the Tempietto of the Volto Santo
The first stage in preparing the work site was to protect the eighteenth-century altar designed by Filippo Juvarra. Multiple levels of scaffolding were constructed to allow restorers to reach even the highest portions of the altar structure.
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Removing the grilles and pilasters inside the Tempietto
To provide space to move the crucifix and avoid the risk of damaging the decoration during the move, the decision was made to remove the grilles and framing pilasters from the side doors inside the Tempietto.
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Removing the angels and crown
Before stabilizing the crucifix, it was necessary to also remove the crown and the angels made by Augusto Passaglia in the nineteenth century, which will also undergo restoration.
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3D Scanning the Volto Santo
Before proceeding to protect the painted surface of the Volto Santo, it was decided to conduct a complete 3D scan of the crucifix ¹
1 3D laser scanning of the Volto Santo will provide the team an accurate set of data of the crucifix in three dimensions, allowing further digital research and even printing of models of the figure. For more on 3D scanning of sculpture, see: https://www.getty.edu/projects/3d-scanning/
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Tissue consolidation ¹
To protect the artwork during the move, it was necessary to perform tissue consolidation. This involves applying a layer of protective tissue on the surface to prevent paint from being damaged or detached in the subsequent phases of the restoration.
1 This common step in a restoration process provides temporary protection to a painted surface. The restorer applies small pieces of tissue paper to the polychromy using a dilute, water-based adhesive and a brush. This step is fully reversible.
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Removing Textiles from the Baldachin
To move the Volto Santo it was necessary to remove the cloth baldachin and hanging textiles that serve as a backdrop to the sculpture. After numbering and recording each of the metal elements of the baldachin, these elements were removed, allowing the textiles to also be taken down and cleaned.
Textile conservators use a low-suction vacuum and clean through a screen to prevent the vacuum from inadvertently removing threads from the textile.
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The Move
Having completed the preliminary operations to remove obstacles in the chapel and consolidate the crucifix, a structure with two winches ¹ was constructed inside the Tempietto to be able to lift the sculpture. Using an appropriate harness, the Volto Santo was lifted over the altar and brought out of the chapel through a side door. The sculpture was transported across the nave on a cart and placed in the restoration laboratory created in the transept.
1 A winch is an apparatus for safely lifting heavy objects
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Anoxic Treatment
To inhibit possible future attacks by wood-eating insects, the sculpture underwent an anoxic treatment ¹. This was done solely for preventive purposes, as the sculpture has not previously been subject to any major insect damage. The crucifix was wrapped in a film with attached valves, into which nitrogen was progressively introduced to replace the oxygen.
1 Anoxia is the condition of no oxygen. Since wood-eating insect respirate air like other living animals, replacing the atmosphere with a gas that has no oxygen content, such as nitrogen, will asphyxiate and kill the insects, their larvae, and their eggs. This is the preferred method of insect control in artworks. Fumigation, which uses poisonous gas, is also effective but poses risks to the materials of artworks, the environment, and the human operators
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Removing the tissue used for protection and consolidation
Before beginning diagnostic analyses or the actual restoration, the tissue used in consolidation of the sculpture was removed. This tissue protected the painted surface of the sculpture during its move from the Tempietto to the laboratory in the transept of the cathedral.
