Start fabrication

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 broke some supporters in the first place since the error of the laser, but it's not happening to everyone.

cut flipping boards. I am showing front side here, on the rare side, there is burn marks and I could not find a way to get rid of it... I am waiting the black polypropylene back in stock

inserting boards into rotating mechanism

Makerbot 3D print time pulley gear, has a really low resolution actually, which is enough for now. Eventually, I am gonna print it in higher resolution. 

pitch: 2.03mm(MXL), belt width: 3mm, bore size: 1/8'' (3.17mm), 

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. 

I glued the stepper motor on the top piece and it dropped off eventually, anyway, never mind, just for testing. 

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.

I cut off the top of the screws

rotating it in, and leaving half of it out, you get the picture, which is the way how I make them together, and it's pretty reliable as what I expected. 

using a metal rod piercing the aluminum sheets and rotating mechanism

piecing them together, move on more digits...

It took some time to put all rotating mechanism in since the distance between each digit is kinda precise. I have to polish the rod into a right length to make the structure hold two rods from two sides (each digit has a rod, they are separated.) After assemble them together, the tension of each digital between the aluminum board and rotating mechanism of each digit is different. Luckily I am using time pulley system, so it won't affect a lot.