NEMA 23 stepper motor: 56.4 mm face, 47.14 mm hole pattern — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/nema-23-stepper/  (CC BY 4.0)
Basis: NEMA ICS 16 frame size 23 (face and mounting-hole pattern); pilot boss and shaft as commonly supplied; body length varies with torque. Envelope only: the outside of the motor. The windings, rotor and bearings inside are not drawn.
Catalog version: 2026-10-20

Sizes: see table below
- Envelope only: the outside of the motor. The windings, rotor and bearings inside are not drawn.
- NEMA 23 is a 2.3 in face: 56.4 mm square, with chamfered corners. The face and hole pattern are the standard; the body length is the maker's.
- Four Ø5.1 through holes in the flange on a 47.14 mm square, for screws from the front.
- Pilot boss Ø38.1 × 1.6; shaft Ø6.35 × 21 from the boss, D-flat 5.71 across.
- Files: 56, 76 mm bodies. Leads and connector are not drawn.
- In DIY Stirling builds, a stepper turned by the engine is used as a two-phase generator; each coil pair gives AC that is rectified for a load.

feature  mm
face  56.4 × 56.4
hole pattern  47.14 × 47.14
holes  4 × Ø5.1 through
pilot boss  Ø38.1 × 1.6
shaft  Ø6.35 × 21, D-flat 5.71 across
body lengths drawn  56, 76

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Wikipedia: Stepper motor — web — CC BY-SA 4.0 (text) — https://en.wikipedia.org/wiki/Stepper_motor
- NEMA: ICS 16 motion/position control motors and controls — PDF — NEMA standard, purchase — https://www.nema.org/standards/view/motion-position-control-motors-controls-and-feedback-devices

Free files (CC BY 4.0, Xem Studio; STEP + STL, 2 parts): https://xemstudio.com/files/hardware/nema-23-stepper/index.json
API: https://xemstudio.com/api/geometry?object=nema-23-stepper