NEMA 42 Stepper Motor: The Largest 110mm High-Torque Frame
The NEMA 42 stepper motor is the largest standard stepper frame, built for the highest-torque axes a stepper can drive. With a 110mm × 110mm faceplate, it delivers torque measured in tens of newton-metres, which is why it goes into large CNC machines, heavy gantries, and industrial positioning where a NEMA 34 runs short. A 2-phase NEMA 42 hybrid stepper motor delivers holding torque from about 8 N·m up to 28 N·m depending on body length, at a 1.8° step angle. The NEMA 42 size (frame) is fixed at a 110mm faceplate, with body length the main variable that sets torque.
Key Specifications at a Glance
| Parameter | Specification |
|---|
| Frame Size | 110 × 110 mm |
| Step Angle | 1.8° (200 steps/rev) |
| Phase | 2-phase (bipolar) |
| Holding Torque | 8–28 N·m |
| Rated Current | 5.0–6.0 A/phase |
| Body Length | 95–201 mm (varies by model) |
| Shaft | 19mm with keyway |
| Lead Wires | 4-wire
|
Typical Applications
NEMA 42 is reserved for the heaviest stepper-driven axes. Common applications include:
- Large CNC routers and mills — big-format gantry and table drive.
- Plasma and waterjet cutters — heavy gantry systems.
- Industrial automation — large conveyors, lifts, and indexing tables.
- Press and forming machines — high-torque feed and positioning.
- Heavy material handling — winders, reels, and large feeders.
- Stage and rigging — heavy-lift and motion systems.
With a NEMA 42 gearbox the same frame drives a high-force linear actuator or a very-low-speed, very-high-torque axis; a dual-shaft version adds a rear shaft for an encoder. Mounting brackets are available for machine integration.
NEMA 42: The Top of the Stepper Range
NEMA 42 is the largest standard stepper frame, so there's no larger stepper to step up to. When an axis needs more than a NEMA 42 can give, there are two paths:
| Need | Solution |
|---|
| More torque, low speed | Add a gearbox to the NEMA 42 |
| High torque at high speed | Move to an AC servo motor |
| Position feedback, no lost steps | Add an encoder or move to a servo |
A NEMA 42 holds high torque cheaply at low speed, but torque falls as speed rises. If the axis runs fast and heavy, an AC servo motor is usually the better answer. Our engineers can size either one for your load.
Customization Options
Cymotorix NEMA 42 stepper motors can be customized for OEM integration. As a NEMA 42 stepper motor manufacturer and supplier, we produce them to your specification. Common modifications include:
- Shaft diameter and length adjustment (standard shaft is 19mm with keyway)
- D-cut, flat, or keyed shaft for direct coupling
- Dual-shaft output for a rear encoder or second load
- Custom lead wire length and connector type
- Winding parameters modified to match your driver voltage and current
- Rear-shaft extension for encoder mounting
- Mounting bracket for machine integration
- Planetary or worm gearbox integration for higher output torque at low speed
How to Drive a NEMA 42 Stepper Motor
NEMA 42 motors are 2-phase bipolar steppers, so they run on a 2-phase stepper driver — but a high-current, high-voltage one. Rated current is around 5.0 to 6.0 A per phase, so the driver must handle that with headroom. We can supply a driver matched and set to the motor if you want the pair tested together.
Recommended supply voltage is 60–110VDC. This frame has high winding inductance, so a high bus voltage is essential to push current in fast and hold torque at speed. Set the driver's current limit to the motor's rated current so the windings don't overheat.
