Previously, I designed a gear set on a heart for Valentine's Day (http://www.thingiverse.com/thing:242304) that requires fixing the gears in place by melting, hence deforming, the tops of the gears' axles. This works, but is very tricky since PLA (my favorite filament type) melts really easily. It demands a very light touch!
I finally was able to produce a design that allows easy snap-together construction. This is it!
I should mention that the gears presented here are essentially the same as before, but have slightly larger center holes. Any old gears you have can be used with the new bases, but it would be easier to enlarge the holes before snapping the gears in place.
Size: approx. 2" high x 1-3/4" wide (5 cm x 4 cm)
NEW: Please check out the frames for the pin & pendant that make for a more finished look at http://www.thingiverse.com/thing:422248.
I printed with 0.2mm layer height, 3 shells, and 30% infill. The latter may be unnecessary, but I was looking for strength.
In one example, I dry brushed (sort of) dark red acrylic paint on the base (excluding pins) and gold acrylic on the gears. The other two are entirely printed. One has golden gears - really shiny! - made of BuMat PLA 1.75mm Gold Filament.