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I went through a few ideas before sticking with the yin-yang ring idea. You can see some in my sketches below.
Execution: 3D Modeling
I then modeled my sketch on Solidworks. It's important to note that I began modeling only after I was confident about what I was going to model. That means I had sketches for different views of the ring like from the top, side, and front. I also wanted this ring on my pinky finger, so I measured the width of my pinky knuckle with calipers since everything had to be precise.
With my design ready, I exported my model as a .STL file in order to be processed by Cura, the software used by the Type A printers used later.
Execution: 3D Printing
I proceeded to 3D print my model and I had to iterate on the measurements in small increments in order to get the fit as precise as possible. It turns out that 3D printers don't print as accurately as your model file. Something to be conscious about when 3D printing. Unlike the Cura image above, I actually printed the ring upside down in order to eliminate the need for any support material.
That being said though, printing my ring as one piece made it weak and aesthetically deformed a bit. Things broke due to the way layers are being printed. In the end, I printed the ring and yin-yang symbol separately, laying the ring on its side in Cura in order to strengthen the print. I used CA adhesive aka superglue to glue the ring band and yin-yang together.
Print one in black and print one in white!