My daughter was about to turn 18, and she really likes Infinity Train, which is a bit obscure: a surreal animated series. I'd wanted to do more jewelry, and I'd done a few rings, so I designed these earrings based on One-One.

Here's the wax pattern cast from the 3D print, in blue. Oh hey, it worked.

Then I tried again, with what I thought was a better sprue design. This one is printed in grey resin.

That earring is slightly convex, like a contact lens. I failed many times to cast it in brass and aluminum bronze, but I learned a lot doing it. In the end I just printed it and spray-painted it.

The next year, my younger daughter had another Pi Day earring concept in mind: a sphere made up of the digits of pi. I worked through the math for it in OpenSCAD.

This was the prototype, printed in white resin and coming together a few days before Pi Day. The design is hers.

The finished earrings were done just under the wire on March 14th. I'm not sure why she wanted black, but they are as ordered.

Here's a better picture, after she highlighted the numbers.

Another look at the prototype.

The first route was a silicone mold. Here's the 3D-printed resin bust of Leonardo da Vinci, the blue silicone mold, and a yellow wax copy made from it. Next stop was going to be a plaster cast of the wax figure.

You can buy two-part casting silicones, but they're expensive and go bad quickly once opened, which makes them a poor choice for occasional home use. So I tried hardware store caulk as a casting medium. Straight out of the tube it's too thick to work well, but I finally hit on a recipe that is thin enough to flow around a model, cures quickly, and uses only easily available, relatively safe stuff.

The cutaway block shows that I could get it to set without voids by using a vacuum chamber. The complete mold shows that it takes detail well.

Amazing Remelt is a good product for this, but I think a homemade version costs about a fifth as much. It's just glycerin and gelatin. Here's the first experiment: the printed mold halves, with a translucent red gelatin casting between them.

And a demold success, with a teal gelatin block holding the impression of the bust next to the resin bust it came from.

The mold parted cleanly along the layer lines. There are some voids from bubbles, so I might need to refine my technique there.

Pouring the wax in stages did the trick. There is one very small area, down at the bottom, where the heat of the wax melted the mold where it was thin, but otherwise it came out great.

I think I'm done with this line of experimentation.