Arduino CNC Shield V3.51 - GRBL v0.9 compatible - Uses Pololu Drivers

The Arduino CNC Shield V3.51 by Protoneer turns an Arduino Uno into a 4-axis CNC controller. Compatible with GRBL 0.9 firmware, it accepts Pololu-style stepper drivers (sold separately) and supports up to 4 stepper motors for CNC routers, laser cutters, 3D printers, and other precision motion projects.

Version 3.51 adds noise filtering circuitry on all end-stop and probe pins, eliminating false triggers and allowing the use of non-shielded cable. The compact shield stacks directly onto an Arduino Uno.

Key Features

• GRBL 0.9 Compatible – Open-source G-code parser and CNC controller firmware
• 4-Axis Support – X, Y, Z, and A axis (A can duplicate any axis or run independently with custom firmware)
• Noise-Filtered End Stops – Filtering on all 6 end-stop pins and probe pin (new in V3.51)
• Pololu Driver Sockets – Accepts A4988, DRV8825, and compatible stepper drivers
• Micro-Stepping Jumpers – Configure micro-stepping resolution (up to 1/32 with DRV8825)
• 12–36V DC Input – Wide voltage range (36V requires DRV8825 drivers)
• Coolant Enable Pin – Control spindle coolant from G-code

Specifications

• End Stops: 2 per axis (6 total)
• Motor Connectors: 4-pin Molex or solder pads
• Power: 12–36V DC
• Compatible Drivers: Pololu A4988, DRV8825, and pin-compatible modules

Ideal For

• DIY CNC routers and milling machines
• Laser cutter and engraver builds
• 3D printer electronics
• Any project requiring precise stepper motor control

Package Contents

• 1× Arduino CNC Shield V3.51

Resources

• GRBL Firmware (GitHub)
• Protoneer Community Forum