Stepper Motor And Driver

The NEMA numbers define standard faceplate dimensions for mounting the motor. They do not define the other characteristics of a motor.

Two different NEMA 17 motors may have entirely different electrical or mechanical specifications and are not necessarily interchangeable.

NEMA 17 - 43.18mm faceplate, is a common size used in 3D printers and smaller CNC mills. Smaller motors find applications in many robotic and animatronic applications.

Great for testing using a development board because it is cheaper than other bigger motors.

NEMA 23 - 56mm faceplate, is a common size used in big 3D printers and small to medium CNC mills up to 1000mm.

The larger NEMA frames are common in CNC machines and industrial applications.

NEMA 34 - 86mm faceplate, is a common size used for replacing larger Milling, Lathe machines, Brake Press,  can be used to build larger CNC machines up to 3000mm or more.

Some may want to use an additional gear reducer to increase torque.