Torque measuring tool (AKA newtonmeter-tester AKA Torque-bar)

As written above, I cut a straight ¼" hex slot in order to have the possibility of using the tool with a ¼" adaptor. I also cut a small hole on the scale side, so it can be used with a scale that pulls a thread, like a luggage scale, instead of a kitchen scale. Note that a kitchen scale can still be used with this remix, same as for the ¾" nut.

Last but not least, thanks much to A_R_B for a great torque wrench and bar designs, with tolerances that print right on the spot with my setup (all parts printed in PLA).

Update : re-drawn on Jan 15th 2023