CNC Expansion Shield V3 + 4pcs A4988 Stepper Driver For Arduino Uno Mega2560

Product Description

Complete Motion Control Solution for CNC, 3D Printing & Robotics

Transform your Arduino UNO or MEGA2560 into a powerful 4-axis stepper motor controller with this complete CNC Shield V3 kit. Including four A4988 stepper drivers and heat sinks, this shield is the industry-standard solution for DIY CNC routers, laser engravers, 3D printers, and multi-axis robotics projects. Compatible with GRBL firmware, it converts G-code commands into precise stepping signals for professional-grade motion control.

Key Technical Features

🔧 Plug-and-Play 4-Axis Control

• 4× independent stepper motor channels (X, Y, Z, A/Clone)
• Hot-swappable driver sockets accept A4988 or DRV8825 drivers
• Color-coded connectors (Yellow/Red/Blue) for easy wiring identification
• Onboard Enable/Reset button for quick motor control
• Limit switch inputs for each axis (6 total) with pull-up resistors

⚡ Flexible Power Architecture

• Motor power input: 12-36V DC via screw terminals
• Logic power: Derived from Arduino 5V rail (no separate supply needed)
• Separate motor/logic grounds prevent noise coupling
• Polarity protection on power input
• Compatible with standard ATX/bench power supplies

🎛️ A4988 Stepper Drivers (4× Included)

• Current rating: 1A continuous, 2A peak (with cooling)
• Voltage range: 8-35V (max 35V for A4988, 45V for DRV8825)
• Microstepping: Full, 1/2, 1/4, 1/8, 1/16 step resolution
• Built-in protection: Thermal shutdown, overcurrent, short circuit, ground fault
• Adjustable current limiting via onboard potentiometer
• Heat sinks included for thermal management

📡 GRBL Firmware Compatible

• Pre-configured for GRBL 0.8+ (also works with GRBL 1.1)
• Converts G-code to step/direction signals in real-time
• Compatible with popular CAM software: Fusion 360, Easel, bCNC, Universal G-code Sender
• Serial communication via Arduino USB (no additional interface needed)
• Spindle/laser PWM control via dedicated pin

🔌 Comprehensive I/O

• Spindle control: PWM output + direction + enable
• Coolant control: Flood + mist outputs
• Abort/Hold/Resume buttons with debouncing
• Endstop inputs: Min/max for X, Y, Z axes
• Cloning jumpers: Duplicate X/Y/Z to A-axis for dual-motor setups

Technical Specifications

CNC Shield V3

A4988 Stepper Drivers (4× Included)

What's Included

• 1× CNC Shield V3 expansion board (red PCB)
• 4× A4988 stepper motor drivers
• 4× Aluminum heat sinks for A4988 drivers
• Online Installation and Operating Instructions
• Complete kit—ready to mount on Arduino

Not Included:

• Arduino UNO/MEGA2560 board
• Stepper motors
• Power supply (12-36V DC)
• Limit switches or wiring

Perfect For

✅ DIY CNC Routers – 3-axis milling machines for wood, plastic, aluminum
✅ Laser Engravers – CO₂ or diode laser cutters with X/Y gantry control
✅ 3D Printers – RepRap, Prusa-style cartesian or CoreXY builds
✅ Pen Plotters – Automated drawing machines and vinyl cutters
✅ Camera Sliders – Multi-axis motion control for time-lapse photography
✅ Pick-and-Place Machines – SMT assembly automation
✅ Robotic Arms – 4-DOF articulated manipulators
✅ Educational Projects – Learn G-code, motion control, and embedded systems

GRBL Firmware Overview

GRBL is the industry-standard open-source motion control firmware for Arduino-based CNC systems. It interprets G-code commands (the universal language of CNC) and generates precise step/direction pulses for stepper motors.

Key Features:

• Real-time motion planning with look-ahead acceleration
• Arc interpolation for smooth curved paths
• Feed rate override and spindle speed control
• Homing cycles with limit switch detection
• Soft limits to prevent crashes
• Configurable via serial commands (no recompilation needed)

Getting Started:

1. Flash GRBL firmware to Arduino UNO via Arduino IDE
2. Mount CNC Shield V3 on Arduino
3. Connect stepper motors and power supply
4. Configure GRBL settings via serial terminal (baud rate, steps/mm, acceleration)
5. Send G-code from CAM software or manual commands

Common Applications & Motor Configurations

3-Axis CNC Router:

• X-axis: NEMA 17 (1.5A, 200 steps/rev)
• Y-axis: NEMA 17 (1.5A, 200 steps/rev)
• Z-axis: NEMA 17 (1.0A, 200 steps/rev)
• A-axis: Unused or cloned to Y for dual-motor gantry

Laser Engraver:

• X-axis: NEMA 17 (1.0A, 200 steps/rev)
• Y-axis: NEMA 17 (1.0A, 200 steps/rev)
• Z-axis: Optional focus control
• Spindle output: PWM to laser driver (0-5V or 0-12V)

3D Printer (Cartesian):

• X-axis: NEMA 17 (1.2A, 200 steps/rev)
• Y-axis: NEMA 17 (1.2A, 200 steps/rev)
• Z-axis: NEMA 17 (1.0A, 200 steps/rev)
• A-axis: Extruder motor (NEMA 17, 1.0A)

Upgrade Path: A4988 vs. DRV8825

This shield accepts both driver types—simply swap them out:

Recommendation: Start with included A4988 drivers. Upgrade to DRV8825 if you need:

• Higher voltage motors (36-45V)
• Smoother motion (1/32 microstepping)
• Quieter operation

Arduino Uno or Mega are not included - shown in the photo for illustrative purposes only.