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I used Emmett's rotating gear code from the heart gear, and mashed it up with the CT scanned skull. I tried a few orientations, I like this one the most because it splits down the middle of the face.
Print out the center, 4 sets of pins, and one of each gear. Snap together, rotate, and marvel.
This was printed on my Up!, I haven't tried it yet on the Replicator. I printed using support, because of an overhang on the eye socket.
EDIT 8/2/12 So I accidentally had uploaded an earlier version of the skull. It should still have come together, but would look a little different from the picture. I have now uploaded the newer version.
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