Bipolar Stepper Motor with Planet Gear Box (18kg.cm)

Bipolar Stepper Motor with Planet Gear Box is a compact high‑torque motion control solution designed for precision mechanical systems and robotics platforms. A 1.8° step angle delivers 200 steps per revolution, while an integrated 5.18:1 planetary gearbox significantly amplifies output torque for demanding positioning tasks. The geared stepper assembly features a 42mm square motor body, a durable 8mm D‑type output shaft, and color‑coded coil wiring for straightforward integration. Compatibility with motion controllers such as Arduino ecosystems and dedicated drivers including the Dual Bipolar Stepper Motor Shield for Arduino (DRV8825) enables precise speed and position control in automated systems.

Note: please carefully confirm techical details (torque, dimension, mounting, etc) for your project(s) before purchasing.

Planetary Gearbox for High Torque Output

An integrated 5.18:1 planetary gearbox boosts mechanical torque far beyond that of a standard stepper motor. This configuration allows the geared motion unit to deliver up to 18kg·cm (176N·cm) holding torque at 200rpm, supporting applications requiring strong rotational force with controlled stepping accuracy. Planetary gearing distributes load across multiple gear teeth, improving durability and torque density while maintaining compact mechanical dimensions suitable for robotics, CNC mechanisms, and precision automation platforms.

Precise 1.8° Step Resolution

A 1.8° step angle provides 200 discrete steps per revolution, enabling fine‑grained positional control for motion systems. This bipolar stepper configuration supports smooth incremental movement, making the motor assembly suitable for equipment that requires repeatable positioning accuracy such as 3D printers, robotic joints, and automated linear actuators. When paired with advanced drivers like the TB6600 Stepper Motor Driver, microstepping control can further enhance motion smoothness and resolution.

Compact Mechanical Structure with Easy Mounting

A 42×42×40mm motor body combined with a 36mm diameter planetary gearbox keeps the motion module compact while preserving strong mechanical output. Four M3 threaded mounting holes simplify installation onto frames, brackets, and robotic assemblies. The 8mm D‑type shaft ensures reliable coupling with gears, pulleys, and lead screws. Color‑coded wiring (black/green for one coil, red/blue for the other) streamlines electrical connections during rapid prototyping and system integration.

Figure: Product dimension diagram

This geared stepper motor is widely used in motion‑control projects ranging from robotics mechanisms to creative maker builds. Example applications include automated props such as the project described in How to Make A Terrifying Halloween Gadget, where a microcontroller like DFRduino UNO R3 - Arduino Compatible, motor driver shields, and modules such as DFPlayer - A Mini MP3 Player For Arduino and Gravity: Digital PIR (Motion) Sensor For Arduino combine to create interactive mechanical effects.

• 1.8° step angle providing 200 steps per revolution
• Integrated 5.18:1 planetary gearbox for enhanced torque output
• High holding torque up to 18kg·cm (176N·cm) with gearbox
• Compact 42×42×40mm motor body with 36mm gearbox diameter
• 8mm D‑type output shaft for secure mechanical coupling
• Color‑coded coil wiring for simple electrical identification
• 4 × M3 threaded mounting holes for easy installation
• Compatible with common stepper motor drivers and microcontroller platforms

• Model No: 42BYGH40-18-22A-C5.18
• Step Angle (degrees) :1.8
• 2 Phase
• Voltage: 3.4V
• Current: 1.0A
• Resistance: 1.7±10% Ohm/Phase
• Inductance: 4.3±20% mH/Phase
• Holding Torque: 3600 g.cm
• Detent Torque: 400 g.cm
• Insulation Class: B
• Life: 6000 hours
• Gear Ratio: 5.18:1
• Hold Torque with Gearbox: 18kg·cm (176N·cm) (200rpm)
• Dimension: 42×42×40mm(1.65x1.65x1.57")
• Mounting: 4 x M3

• Stepper Motor with Planet Gear Box ×1

• Printer
• 3D Printer
• CNC
• Robotics
• Linear Actuators