Set Screw Size & Torque Selection
Find the recommended set screw size, seating torque, and holding power for your Free-Flex® pivot
Overview
When mounting a Free-Flex® pivot with set screws, the screw size and seating torque must be matched to the pivot diameter to provide adequate holding power without distorting the flexures. Use the lookup below to find the recommended set screw for your pivot, then refer to the full table for complete specifications. Cup point set screws are recommended.
Max Holding Torque
Maximum torque required to rotate a -400 series pivot to its maximum recommended travel position.
Torsional Holding Power
The torque the set screw can resist about its own axis before the pivot rotates within the housing — the resistance to twisting of the pivot body relative to the mounting bore.
Full Set Screw Reference Table
| Pivot Dia | Set Screw Size | Seating Torque | Max Holding Torque | Holding Power | Torsional Holding |
|---|---|---|---|---|---|
| 0.125" | #0 | 1 in·lb | 0.082 in·lb | 50 lb | 3 in·lb |
| 0.1562" | #1 | 2 in·lb | 0.164 in·lb | 65 lb | 5 in·lb |
| 0.1875" | #3 | 5 in·lb | 0.268 in·lb | 120 lb | 10 in·lb |
| 0.25" | #4 | 5 in·lb | 0.658 in·lb | 160 lb | 20 in·lb |
| 0.3125" | #5 | 10 in·lb | 1.314 in·lb | 200 lb | 30 in·lb |
| 0.375" | #8 | 20 in·lb | 2.22 in·lb | 385 lb | 70 in·lb |
| 0.5" | #10 | 35 in·lb | 5.264 in·lb | 540 lb | 135 in·lb |
| 0.625" | 1/4" | 80 in·lb | 10.512 in·lb | 1000 lb | 310 in·lb |
| 0.75" | 5/16" | 160 in·lb | 18.098 in·lb | 1500 lb | 560 in·lb |
| 1" | 3/8" | 275 in·lb | 43.301 in·lb | 2000 lb | 1000 in·lb |
All values are in imperial units. Holding torque and power assume cup point set screws seated to the listed torque.
Installation Cautions
- • Hole diameter should be 0.0005 to 0.0015 inch larger than the pivot diameter.
- • Use caution when tightening — do not crush or distort the pivot.
- • When vibration is anticipated, standard screw locking methods should be used.
- • Values are guidelines for cup point set screws; actual holding power depends on housing material and finish.
Need help with a non-standard size or high-vibration application?