Quite a few years ago, Thingiverse member "Emmett" created this wonderful geared heart: https://www.thingiverse.com/thing:243278. After I printed and assembled one, many who attempted to operate it pinched their fingers between the heart gear pieces. So I created "Geared Heart Version 2.0" which is Emmett's heart mechanism mounted on a base of my design with a knob underneath, allowing the heart mechanism to be operated without finger pinching.

I originally published "Geared Heart Version 2" in December of 2016 with a link to Emmett's 2-3 heart gear parts. This version includes the remixed file "Emmett's Parts.stl" containing only the required 2-3 parts.

Designed using Autodesk Fusion 360, sliced using Cura 4.4.1, and printed in PLA on an Ultimaker 3 Extended and an Ultimaker S5.

Supplies

Glue.

Step 1: Parts.

The parts are a mixture of Emmett's original heart pieces, pieces I remixed and pieces I designed. I printed all parts at .15mm layer height, 20% infill with no supports. The parts include:

"Base and Gear Heart Bottom.stl", the base and the gear heart bottom combined.
"Base.stl", the base if planning to glue the heart base to the base.
"Emmett's Parts.stl", Emmett's "HeartGears2-3.stl" with unused parts removed.
"Gear Heart Bottom.stl", my remixed heart bottom that is glued to the base.
"Heart Center.stl", my remixed heart center with a drive shaft added for the knob.
"Knob.stl".

The base can either be printed in one single extrusion piece ("Base and Gear Heart Bottom.stl") or in two pieces ("Base.stl" and "Gear Heart Bottom.stl") which are subsequently glued together.

Prior to assembly, test fit and trim, file, drill, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on you printer, your printer settings and the colors you chose, more or less trimming, filing, drilling and/or sanding may be required. Carefully file all edges that contacted the build plate to make absolutely certain that all build plate "ooze" is removed and that all edges are smooth. I used small jewelers files and plenty of patience to perform this step.

Step 2: Assembly.

I followed Emmett's assembly video to assemble his heart pieces to "Heart Center.stl", making certain to trim, file and/or sand components as necessary for very smooth operation of each piece.

If the base was printed in two pieces, glue "Gear Heart Bottom.stl" to top of "Base.stl" making certain the holes are perfectly aligned to accept the heart center drive shaft.

Slide the heart center drive shaft down through the heart bottom gear and through the base, then secure in place with "Knob.stl".

And that is how I 3D printed and assembled "Geared Heart Version 2.0".

I hope you enjoy it!