ER Collet Torque Calculator
Using the correct torque ensures maximum grip while maintaining the lowest possible Total Indicated Runout (T.I.R.).
T.I.R. & Accuracy
Over-tightening an ER collet nut deforms the precision taper and "craters" the bearing surfaces, which leads to high runout that cannot be fixed.
Torque Reference Chart (Nm)
| Size | Recommended | Max |
|---|---|---|
| ER11 | 17 Nm | 24 Nm |
| ER16 | 42 Nm | 56 Nm |
| ER20 | 56 Nm | 80 Nm |
| ER25 | 104 Nm | 136 Nm |
| ER32 | 136 Nm | 170 Nm |
| ER40 | 176 Nm | 220 Nm |
The "Hand Tight" Myth
"Tightening it as hard as you can" with a standard wrench often exceeds recommended torque by 300%. Always use a dedicated torque wrench for critical finishing operations.
Tip: Clean and lightly oil the nut threads and the taper surface regularly to ensure consistent torque readings.