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Orpheum Auditorium Plaster Moulding Restoration & Fabrication, Champaign

Many of the mouldings that once graced the auditorium of the Orpheum Theatre (now the Orpheum Children’s Science Museum) were severely damaged. Quite a number of these were on the 32-ft. high ceiling. Altogether, over 60 mouldings of various kinds had to be recreated. The “rib” (below) is roughly 8′ x 2′. The smallest of the ceiling mouldings is 5′ x 1′.

In February of 2009, New Prairie began work on the auditorium by removing mouldings from the ceiling, either for repair or to be used as templates for the new ones. Although these pictures look full of light, it was actually very dark and very cold in the unheated auditorium!

A U of I architectural restoration class was invited to our warehouse to learn the process of recreating the mouldings. The original moulding is shellacked first, to make it easier to peel off the hardened latex that will be applied. The latex must be mixed: the yellow substance is like dough; the blue is very sticky. Once they are mixed, they are bright green. In the pictures below, the Restoration class and New Prairie carpenter Jen Hansen are painting on the blended latex with small paintbrushes. Care must be taken to fill every crack and crevice to get an accurate representation of the original.

Next we mix Gypsolite, a lightweight gypsum basecoat plaster with perlite aggregate, and layer it on top of latex. Now we have the original, a layer of latex, and the layers of Gypsolite. The Gypsolite constitutes the “mother mould.” Once it is all dry, the whole thing is flipped, and the original removed.

Finally the mould is ready for plaster. Precautions are taken to avoid plaster getting in between the mother mould and the latex layer. Jute is added to the second, thicker coat to make it stronger. 

Once the plaster is dry, the whole piece is flipped on to its side and the mother mould is pried gently away. Then the latex is peeled from the finished moulding. The same process was applied in miniature to some of the bullseyes over the Orpheum doorways. Finished mouldings spent weeks in the shop curing before they were installed.

For more pictures of the finished ceiling, see Orpheum Auditorium Ceiling Restoration.

Note: The words “molding” and “moulding” are the same, but we have used the primarily British “moulding.” Also, “moulding” can be used interchangeably with just plain “mould.”

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