Replying to @⁨solbt@feddit.org⁩

P. L. Robertson invented the Robertson screw and screwdriver in 1906 and received the Canadian patent in 1907 (CA103387, U.S. patent CA103387A) and US patent in 1911 (U.S. patent 1,003,657) for a manufacturing machine. The cold forming was a separate patent.

Roberston refused to license to the US and Henry Ford because Ford was being a dick.

en