Building Bigfoot, part three

This is the third post in this series: for part one, go here. In part two, we saw how the body of the piece is cast and then carved from expandable urethane foam, and now let’s have a look at the finished mannequin:

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Front view of the finished mannequin

Side view of the mannequin

Side view of the mannequin

Most of the body will be covered in hair, so further anatomical details aren’t really necessary. The face and hands, however, are hair-free, and so need to be treated in more detail. They are first modeled in plasticine, as seen below.

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Closeup of the hand modeled in plasticine

Both the face and hands are modeled after those of gorillas and orang-utans: notice the short thumb, placed far back on the hand, and the heavy, deeply curved nails. The prominent brow ridge, the bridgeless nose and large nostrils are nearly identical to those of a gorilla, but I have actually flattened the face and reduced the chin in comparison, so that he looks slightly more human, or at least humanoid. The eyes in this model are not the final glass eyes for the finished piece; they are a pair of ungulate (elk, I believe) eyes I had left over from a previous project. They are inappropriate for a primate because of their aspherical shape and lack of sclera (whites). I have the final eyes on order from Tohickon, who make the best glass eyes in the business.

Plasticine model of Bigfoot's face, in process

Plasticine model of Bigfoot's face, in process

I have also modeled the feet, and, being the easiest of the five cast body segments to reproduce, they will be cast first. A simple one-piece mold is sufficient, with a rubber inner or “blanket” mold surrounded by a plaster support or “mother” mold around it.

The feet with molds on them

Rubber and plaster molds over the feet

I use two different kinds of casting techniques to produce parts like these: epoxy resin suffused with fiberglass, or solid urethane resin. Because the feet are seen only from above, they can be cast as hollow epoxy/fiberglass shells, unlike the hands, which are seen fully in the round and are more easily cast as solid objects. Simple shell castings such as you see below are easier, require less demanding molds, and are more economical than solid urethane castings.

Epoxy resin and fiberglass curing inside the mold

Epoxy resin and fiberglass curing inside the mold

In the photo above, you can clearly see the inner polyurethane rubber mold (it’s blue), which is Por-a-mold 3333TA, a product I really love. It’s easy to mix (1:1 by volume), easy to apply (the consistency is like cake frosting, and will adhere to vertical surfaces, allowing you to take a mold while the part is in place), and requires only a single 3/8″ thick application to create a good mold. The plaster mother mold exists only to hold the rubber mold in place.

Making the casting is straightforward: a splash coat of epoxy resin is painted into the mold first, with an acid brush, and allowed to partially gel (I use a 30-minute set epoxy for this). Then I apply a second layer, followed by strips of fiberglass cloth soaked in epoxy. Once that is at least partially set, I add a second layer of strips, and, depending on the size and structural requirements of the piece, repeat the process.

You can see in the photo above that I have colored the resin. This is done with dry artist’s pigments pre-mixed into the epoxy resin before adding the hardener. Tinted resin actually makes it easier to see what you’re doing inside the mold. Despite the fact that the piece will be painted, tinting the resin to a color approximating the baseline tone of the finished piece is helpful in that if the piece is scratched, it’s less noticeable.

Pulling the rubber mold from the epoxy casting

Pulling the rubber mold from the epoxy casting

In the photo above, you can see the resin positive being exposed by pulling away the rubber mold.

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The foot cast in resin, primed, and attached

Since the feet themselves are hollow shells, they can be attached right over the cores of the feet that were constructed into the armatures. The undersides of the feet consist of two thicknesses of 3/4″ plywood screwed to the wooden armature, and covered with a layer of yellow urethane foam. The epoxy shells are affixed to the foam with liquid epoxy, and the transition is smoothed out with some epoxy putty. They are then primed with tinted gesso (I use Golden artist’s absorbent ground tinted with dry pigments) and readied for final painting.

Next, on to the  hands.

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  • [...] is part 4 of this series, you can see part three here. In the last installment, we saw the process for casting a body part as a hollow fiberglass and [...]

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