EverGreene was invited to the Plastering & Spray Fireproofing Contractors Union Conference at New York City’s historic Roosevelt Hotel. Project Manager Toldand Grinell and Master Plasterer Anthony Kerstens demonstrated how to cast sculptural ornament in plaster. Using one of EverGreene’s decorative molds, they displayed the precision and care necessary for fabricating a perfect plaster cast.
A plaster cast is a precise replica made from a three dimensional form. The original object can be anything from a sculpture, to a building, to a face. The mold (made of clay, gelatin, urethane or plaster) is sprayed with a release agent so that it will easily separate from the set plaster. Dry plaster is saturated with water to form a smooth paste. It is poured into the mold and manipulated—either by pushing it down with a brush, or agitating the encapsulating form persistently by lightly tapping or vibrating the work surface— into all the recesses of the mold, ensuring that there won’t be any bubbles in the final plaster work. This first layer of plaster is covered with a fiber glass veil which adds structure to the final product. Burlap or hemp can also be used to add strength. A second layer of plaster is then poured into the mold, filling it completely, and scraped with a putty knife, to create a smooth, level surface. The plaster is then left to harden. After a few hours, the mold will peel away from the newly set plaster object, leaving behind a flawless cast.
The practice of plaster casting began in the sixteenth century when Leone Leoni assembled a collection of casts in Milan. In the 18th and 19th centuries there were vast collections of plaster casts in major metropolises such as Berlin and Paris. These plaster cast collections were used as didactic tools for scholars to study without having to travel abroad to see the original artwork. Today, plaster casts are used in many fields, ranging from fine art to medicine. EverGreene artisans and conservators use plaster casts to both replicate historic elements and fabricate contemporary designs.