We've been learning how to cast. The material is a rubber that comes in a big sheet, marked out in 2" cubes, that you cut off and put in a pyrex measuring cup, then pop into the microwave for about a minute. It's insanely sensitive to overheating, at which point it turns a horrible yellow and starts producing carcinogenic fumes, and has to be put in the fume cabinet and tossed out. Once it is melted, you dab it onto the object you want to cast, trying to get in every nook and cranny. It starts cooling off quickly, so the melting and dabbing and cooling process has to be gone through many times before the object is adequately coated. When it's coated, about a 1/4" thick, it can be peeled off intact and put on again many times, as it it both strong and flexible. The next step is to coat the thing with layers of mud rock (plastering strips), let it dry, paint it with polyvinyl acetate (adhesive that dries rock hard), and let it dry. You now have the rubber cast and the hardened plaster to keep its shape.
It's remarkable because it can be used on almost anything and does not mar the surface. I did a wood carving, and Andreas did a bronze statue of Narcissus, just the head and shoulders. The point of this is to give us experience with casting and gilding. This coming week we will finally start gilding. We'll be gilding the leaves we made for the chandelier, as well as the objects we have cast. We're also making objects for other classes to guild. That's one of the neat things about the school --when one class needs something for a lesson, the material often comes from the project of another department. For example, the chessboards that we are learning to French Polish were made by a woodworking class.
I'm including a picture of the classroom full of project chairs undergoing restoration and French polishing. I French polishing this week, on the chessboard, but all around me the Second Year BA's were working on chairs that they had done all the conservation and restoration on, making a leg here, replacing a carved bit there.
I really hope I get to carve something; I find myself drawn to the material. I really like working on the Gimson chair, especially the hand work, like making mortises, even though we're almost never allowed to go work on it. There's a certain free-flowing shape to the day with Campbell, and if we're up to our elbows in some process, he keeps us. So the chair is progressing very slowly. But I will be insufferably proud when it's done.
One of our lectures this week was on making size wash. (That's size as in glue.) It's something you would put on a new piece of timber that you want to look consistent with the old wood, and it was also used in places where there might be lots of humidity, such as a linen press, because the wash is tough and water resistant. It's made of twelve parts water, one part glue ("Scotch glue", pearl glue, hide glue are all names for it) and earth pigments. The pigments to imitate different kinds of wood are:
-- Red ochre: mahogany
-- Yellow ochre: old pine
-- Slate umber: dirty old runners and dust boards.
This pertains directly to something Kate and I were unclear about, back in Marshfield with our last camel-back sofa: should we attempt to make new wood repairs to the frame look old? The answer is yes, and size wash would be one way to do it.
We also learned how to make black lacquer, which is an opaque shellac like what you see on a japanned box, so that you see nothing of the grain of the wood. The magic ingredient is soot.
Oh yes: about the pictures at left and below! Remember the rubbery stuff, used in casting? Well, I took a picture of Lucinda working on something while the goo dried on a bronze bust. When it was done, Andreas carefully applied the plaster to the outside. The final picture shows the mold -- cut off of the bronze bust -- and a 
reproduction made out of plaster, which was poured into the rubbery mold. Lucinda treks from London part-time, but Andreas and I are the two foreigners in the Master's Program. He's from Greece, and brought us back some yummy olive spice puree from his last trip to Athens. The only word recognizable on the jar was "Unilever".
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