CNC Shield V3 Expansion Board for Arduino Uno A4988 DRV8825 Compatible GRBL 4-Axis

The CNC Shield V3 Expansion Board turns your Arduino Uno into a powerful multi-axis motion controller. The perfect hardware foundation for DIY 3D printers, desktop CNC routers, laser engraving machines, and custom robotic arms, it stacks directly onto the Arduino Uno R3 footprint and runs seamlessly with open-source GRBL firmware. Four independent driver slots accept A4988 or DRV8825 stepper modules for clean, modular multi-axis control without complex point-to-point wiring.

The 4th axis (A-slot) can be jumper-configured to clone any primary axis (ideal for dual-motor setups) or run independently via D12/D13 for custom firmware. Onboard microstepping jumpers beneath each driver slot allow dynamic resolution switching.

Key Specifications

• Model: CNC Shield V3.00
• Input Voltage: 12V to 36V DC
• Supported Drivers: A4988, DRV8825, and compatible STEP/DIR carrier modules
• Axes: X, Y, Z + configurable 4th A-axis (clone or independent)
• Endstop Connections: 2 per axis (6 total)
• Control Pins: Spindle Enable, Spindle Direction, Coolant Enable
• Firmware: GRBL v0.9 / v1.1 compatible
• Interface: STEP / DIR digital control
• Form Factor: Direct stack on Arduino Uno R3

GRBL Pinout Reference

• X STEP / DIR: Digital Pin 2 / Pin 5
• Y STEP / DIR: Digital Pin 3 / Pin 6
• Z STEP / DIR: Digital Pin 4 / Pin 7
• X / Y / Z Limit Switches: Digital Pins 9, 10, 11
• Spindle Enable / Direction: Digital Pin 12 / Pin 13
• Abort / Hold / Resume: Analog Pins A0, A1, A2

4th Axis Jumper Configuration

• Clone X-Axis: Connect jumpers across X-labeled pins
• Clone Y-Axis: Connect jumpers across Y-labeled pins
• Clone Z-Axis: Connect jumpers across Z-labeled pins
• Independent: Leave jumpers off, control via D12 and D13

Important: When installing A4988 or DRV8825 drivers, match the GND and DIR pin markings on the shield to those on the driver board. Incorrect orientation will instantly damage both the driver and the shield.

Applications

• GRBL-based DIY CNC routers and desktop engraving machines using Arduino Uno
• Laser cutting and laser engraving machine motion control
• FDM 3D printer motion control with A4988 or DRV8825 driver modules
• Multi-axis robotic arms and custom Arduino automation projects

Package Includes

• 1 x CNC Shield V3 Expansion Board
• 1 x Set of Jumpers (for axis cloning and microstepping configuration)

Note: Arduino Uno board and stepper motor driver modules (A4988/DRV8825) are not included and must be purchased separately.

Note: Image is for representation purpose only.