Wednesday, February 22, 2012

Molding/Casting the Key of Cthulhu

OK, I don't have any good pictures of the mold, but I do have a few that show the cast in the mold.  The mold had to be designed so I could plug up the bottom for rotocasting, as well as have all the front tentacles stay as part of the one piece cast.  It was a very difficult procedure, and I did not have as much time as I would like to devote to it myself, so I brought in a friend and former student of mine, Yusuke Mori, to assist.  I would work with him on where the wall went, and he would get to work.  It turned out to be a 4 piece fiberglass case mold with tin based silicone for the inner structure of the mold.  There is a silicone plug in the base that pins in, and I unplug it and pour in new material for each layer of rotocasting.  I have different procedures and materials for the faux bronze vs. the faux marbles.

The Key of Cthulhu peeking out from its mold.
I had to do a similar procedure for the base, but less pieces (only 3).  It is a rotocast mold as well, with fiberglass and silicone.

Base right out of the cast.

I mix various powders into the translucent cold cast resin, along with pigments at various levels of rotocasting.  Also, ballast, to give that realistic hefty weight of either marble or bronze.  Then, of course, the final patina.  With the bronze, I use bronze metal powder in the cast with the pigments, then it's burnished, then a wash and dry patina added with final clear coat.  With the marble, I mix various swirl colors to achieve the marbled look with the marble dust, then the final orange patina and clear coat.  The base is a dry brush patina with clear coat.  The small side tentacles are cast in silicone cylinder molds and solid cast, which are then keyed into the actual bust itself.

Side tentacles, fresh out of their molds, unburnished.
Well, there is the whole process of the Key of Cthulhu!  Here are some final pics of the completed idol.

Key of Cthulhu, faux Marble.

Key of Cthulhu, faux bronze.


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