That is actually a feature of this design. They were the answer to in-line screwdrivers who had no precise stopping torque: cam-out before the thread is damaged.

[–] [email protected] 21 points 2 years ago (1 children)

I know it's an intentional feature, but it's a bad feature. Camming out damages the head of the screw. This exchanges repairability for manufacturing simplicity. Additionally, the sloped shape makes it possible to use slightly oversized or undersized drivers, further increasing the chance of camming out and damaging the screwhead.

[–] [email protected] 2 points 2 years ago

To your point it's a compromised solution for a problem that no longer exists.

[–] [email protected] 2 points 2 years ago

Bug turned into a feature: https://handwiki.org/wiki/Engineering:Cam_out