CNC Shield V4 Expansion Board for Arduino Nano – 3-Axis, A4988/DRV8825, GRBL Compatible

The CNC Shield V4 is a compact expansion board designed to stack directly onto an Arduino Nano and turn it into a three-axis motion controller for CNC engraving machines, 3D printers, laser cutters, and small robotic systems. It provides three dedicated slots for A4988 or DRV8825 stepper motor driver modules, each capable of controlling a two-phase four-wire stepper motor drawing up to 2A. Because each motor channel requires only two I/O pins, the shield manages all three axes using just six digital pins, leaving the remaining Nano GPIO available for other functions. The board is fully GRBL compatible and works with the GRBL firmware running on the Arduino Nano, converting G-code into stepper signals for coordinated X, Y, and Z movement. Jumper caps beneath each driver slot set the microstepping mode, from full-step with all jumpers removed to 16-subdivision with all jumpers fitted. Dedicated headers expose limit-switch (endstop) inputs and an I2C interface for LCD or sensor modules, while a DC 5V barrel jack and a blue screw terminal accept a 7.5-12V motor supply. Measuring 72 × 59 mm and weighing approximately 33 g, this CNC expansion board is a practical, low-cost platform for builders who want a proven GRBL-based motion control setup without custom wiring.

1. Three-axis CNC engraving machines and routers.
2. 3D printers and additive manufacturing platforms.
3. Laser engraving and cutting machines.
4. Small robotic systems and automated positioning stages.
5. GRBL-based motion control projects with Arduino Nano.
6. Educational and DIY CNC builds requiring a compact stepper driver shield.

1. Model: CNC Shield V4 (CNC-SHIELD-V4).
2. Compatible controller board: Arduino Nano.
3. Number of axes: 3 (X, Y, Z).
4. Driver slots: 3 × A4988 or DRV8825 compatible modules (drivers not included).
5. Maximum motor current: 2A per channel (two-phase four-wire stepper).
6. I/O requirement: 2 digital pins per motor channel (6 pins total for 3 axes).
7. Input voltage: 7.5V to 12V DC (motor supply); 5V logic from Arduino Nano.
8. Power input: DC 5V barrel jack and blue screw terminal.
9. Microstepping control: jumper caps per driver slot (full-step to 16-subdivision).
10. Limit switch inputs: exposed ENDSTOP headers.
11. I2C interface: exposed for LCD or I2C modules (shares pins with GRBL probe).
12. Firmware compatibility: GRBL.
13. Dimensions (L × W × H): 72 × 59 × 10 mm.
14. Weight: approximately 33 g.