Adjustable-Torque Thumb Screws
Handles, Knobs & Screw Clamps
Knurled-head thumb screw that exerts positive, repeatable force. Clockwise, the knob de-clutches and turns freely when you reach the desired torque. Counterclockwise, the knob locks for positive retraction. Adjustable-Torque Thumb Screws are furnished with your choice of swivel foot, and a Knurled Check Nut.
Available in body-thread sizes from #10-32 to 5/8-11 (M5 to M16 in metric), each in a choice of several lengths. Due to their small size, #10 and M5 thumb screws have a dog point instead of a swivel foot. Made in USA.
To set desired force, first remove the outer cover screw at the side of the knob, to expose the adjustment screw. Next, insert a hex wrench to turn the adjustment screw until desired torque is achieved. Reinstall the outer cover screw when finished. Torque can be adjusted from 3 to 6 inch-lbs, resulting in a contact force of 10 to 125 lbs, but these values are approximate. Force can vary +/- 30% depending on lubrication and other operating conditions.
Choice of three swivel-foot types. Adjustable-Torque Thumb Screws use our patented left-hand-thread swivel-foot system. The ball end of the body screws into the foot for easy installation and removal. Once the ball threads pass beyond the foot threads, the foot can rotate and pivot freely (20° total angle). Foot threads are left-hand to positively prevent accidental backout during use. Delrin® feet are optional for types A and B. To order with a Delrin® foot, add "N" to the part number, e.g. CL-415-TSAN. Note: Delrin® feet are not threaded – they snap on and off.