Who would have guessed? A while back, a student printed this gear off of Thingiverse. When it printed, we all assumed it didn't work. In theory, it should have worked, but we couldn't get the gears to move. Fast forward a few weeks, and one of the kids was playing around with the 3D printed stuff and stuck an Allen wrench into the center of the gear and voilà - it worked! Seems we just needed a little more torque than we were providing by hand.
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