Fabrication is a time consuming but a fun part. I felt like find myself back when I was majored in industrial design in college.
Based on the info that I've mentioned in the last post here, I started with laser cutting and 3D printing. The rotating mechanism is made by acrylic, the flipping board is polypropylene, if you are in NYC, you can get polypropylene here, they sell acrylic too BTW.
I started building with a composite material, relatively soft but flat. I was using screw to fix two pieces in 90°, however, I end up breaking the material, so I cannot keep it upright. However, through this quick and dirty prototype, I have a better understanding of the dimension of one digit. Also, good to know the distance between stepper motor and the rotating mechanism.
Next step, trying metal material for more reliable inner structure. I was using aluminum sheet. The first problem I was facing is I could not find the right size standoffs that I need... I checked online, OK, to be honest, there is the right size maybe but it is too expensive... It's just for prototyping, I kept reminding myself like this. I found standoffs in shop in 2'' and 1''... I just got a whim that it's gonna be perfect if I could link them together... "WHY NOT!?" This is what I got after that thinking.