Precision spring collets are the standard for firmly clamping shaft tooling into their respective toolholders. Collets are used properly when seated into a collet nut followed by tightening the collet nut onto the respective tool holder. Collets should be replaced every 500 machine hours. If not replaced the collets can lose elasticity and cause tool burn, run out, and even broken tools. Correct clamping force for respective Collets styles are as follows: ER 32 – 100/ft/lbs, ER40 – 130 ft/lbs, SYOZ25/RDO35 90 ft/lbs.