Mechanical binary calculator.
Fullsize image: https://s3-us-west-1.amazonaws.com/h...r_fullsize.jpg
https://s3-us-west-1.amazonaws.com/h...calculator.jpg
Previously:
https://www.homemadetools.net/forum/...896#post108875
https://www.homemadetools.net/forum/...6452#post83701
https://www.homemadetools.net/forum/...631#post132763
