Fully mechanical binary counter that can count up and down. It's modular so you can extend to whatever digit you want.

In order to make a one “component”, you need

zero_side x1

one_side x1

zero x1

one x1

carry_piece x2

connector x1

For Base:

mid_base x(# of components - 2)

left_base x1

right base x1

handle_connector (print with support) x1 

lock (print with support) x1

Then you can add them together and finish the build with handle. I'm leaving this assemble so everybody can play around with. 

V2

[https://cad.onshape.com/documents/f6d0b90611b7d2bdcc9fa510/w/4853c7ce18bd8fc2b67c3fde/e/c1dcc5efb36532eca3db1477](https://cad.onshape.com/documents/f6d0b90611b7d2bdcc9fa510/w/4853c7ce18bd8fc2b67c3fde/e/c1dcc5efb36532eca3db1477)

V1
[https://cad.onshape.com/documents/ba2302744a642a2c7c61b6d8/w/efc27a218cb2c4ba97b978c1/e/34ea1ceb099a65448f088213?renderMode=0&uiState=6686bd3e3061dc322dc8aa94](https://cad.onshape.com/documents/ba2302744a642a2c7c61b6d8/w/efc27a218cb2c4ba97b978c1/e/34ea1ceb099a65448f088213?renderMode=0&uiState=6686bd3e3061dc322dc8aa94)

Print Instructions

Only handle_connector and lock needs support.

Print with the current orientations.

Print lock with 100% infill