Mechanical binary calculator.
Fullsize image: https://diqn32j8nouaz.cloudfront.net...r_fullsize.jpg
https://diqn32j8nouaz.cloudfront.net...calculator.jpg
Previously:
https://www.homemadetools.net/forum/...896#post108875
https://www.homemadetools.net/forum/...6452#post83701
https://www.homemadetools.net/forum/...631#post132763
