On "torque wrenches and spring tension"
Have you seen those torque wrenches that are preset to a certain value? (used in production line work in a factory) The springs in those can't be released so do they need to be re-calibrated more often? I'm guessing yes.
Also... I saw these being used in the local tyre shop on the end of their impact guns. They "give" at a certain torque. I don't know how good they.
