Machine extension bending?

[Dr Rod]

Hello all

I recently read that machine extension parts can bend.

I understand why this would happen, especially with a loud player because you would need more pressure to keep the string down.

My question would be if anyone knows which type of extension machine is more or less prone to this sort of problem.

I remember my teacher at David Walter had a bass with one of the really old machines, the ones with the opening mechanism that you operated with the left thumb. It was really heavy, but I wonder if those ones ever had this sort of bending.