To generate the models, I spun up an instance of ComfyUI on runpod.io using my pre-built docker container. I then used FLUX dev and Hunyuan3D to generate 3D models in their likeness in the style of 3D chibi, kawaii and anime:

From those generations, I then selected the image and model that best represented their likeness then performed an additional sculpting pass with a Wacom on top of the mesh to further clean up and tune the model. Furthermore, I added a simple slot for your finger.

I first thought that I could simply just take silicon caulking tubes and inject them into a simple two part mold. So as a quick experiment, I built such a mold with a cavity in the shape of the object in Onshape, then 3d printed the mold.

However, I then learned that often Caulking silicon is cured through moisture, so that basically just resulted in a mess. I then later learned from a friend that if you empty the caulking tube into a tub of water and distribute water throughout the uncured silicon, you can then use that uncured silicon as the casting or mold making material.

I started learning about making reusable molds where you essentially build physical molds by:

1. Make a physical box that encapsulates the object you want to eventually cast with some kind of place to pour or inject the casting material.

2. Place the object inside the box and fasten it.

3. Fill the box with some kind of curable silicon or urethane.

4. Remove the cured silicon mold from the box and remove the object. 

5. Your ready to cast.

The other option is to design mold in 3D and 3d print the mold box out of PLA which is the approach I took. I was uncertain about how the casting should be removed from the mold. Therefore, I decided to design a system in Blender that would procedurally build a mold making box around whatever object you wanted to cast:

This effectively generates the positive mold that can be used to generate the negative mold of the object you want to cast. The generated mold box has little slots such that the resulting mold can align and mesh together.  I also built a method of visualizing the resulting mold casting:

I also allowed the walls to be removable making it easier to remove the casted mold from the PLA print and added some injection ports and a air release port. Here are some iterations of those molds and a test mold casting using two part platinum curable silicon:

The resulting silicon molds were great, firm but flexible and they slotted together perfectly. Then I started doing some test pours first by using some 0A shore hardness two part silicon, which I found to be too soft and was two difficult to pull out of the mold without tearing. So, then I sprayed the molds with some mold release compound and poured the same 15A silicon I used to make the molds.

The resulting casting wasn't bad. But then I realized that I might not even need this additional step of making a silicon mold. Since making silicon molds is more handy for harder and less flexible castings such as resin. So I changed my geometry nodes workflow a little bit to instead generate the negative mold for the casting instead of generating the mold to make the mold.

Below is the resulting mold that ended up working. Basically, it's a two part mold with one an injection port at the bottom for a syringe to fill the cavity with silicon. Then lots of little air holes on the top of the mold for air to escape.

After that, the numbers just began increasing, and occasionally I'd have to re-print some broken molds to keep the mold numbers up: