Pen Plotter and GRBL CNC 2 axis Control board

Upgraded 2-Axis GRBL Control Board for Pen Plotter & DIY CNC

(Introduction)

Supercharge your DIY pen plotter or delve into the basics of CNC with this enhanced 2-Axis GRBL Control Board. Building upon standard designs, this board offers integrated support for X and Y limit switches and a dedicated servo connection for automated pen up/down control. Save valuable time and resources in your home-built CNC projects with this streamlined and feature-rich controller.

Key Features & Benefits:

• Optimized for 2-Axis Systems:
  • Benefit: Specifically designed for precise control of 2-axis motion, ideal for pen plotting and basic CNC applications.  
• GRBL & BenBox Compatibility:
  • Benefit: Works seamlessly with the popular open-source GRBL firmware and BenBox software, providing a user-friendly control interface and a wealth of online resources.
• Integrated Limit Switch Support (X, Y):
  • Benefit: Easily connect limit switches for both X and Y axes, enabling accurate homing procedures and preventing machine over-travel for increased safety and precision.
• Dedicated Servo Control for Pen Lift:
  • Benefit: Features a dedicated interface to control a servo motor, allowing for automated raising and lowering of the pen in your plotter designs, enhancing efficiency and detail.
• Supports A4988 & DRV8825 Stepper Drivers:
  • Benefit: Offers flexibility in choosing your stepper motor drivers based on your specific motor requirements and desired micro-stepping capabilities.
• Robust Stepper Motor Support:
  • Benefit: Capable of driving 12V stepper motors with a maximum current of 2A (1.5A recommended), suitable for commonly used NEMA 17 (size 42) stepper motors.  
• Arduino UNO Bootloader (ATMEGA328P):
  • Benefit: Powered by the familiar and well-documented ATMEGA328P microcontroller with the Arduino UNO bootloader, making it easy to configure and potentially customize.  
• Reliable USB Connectivity (CH340):
  • Benefit: Utilizes the common CH340 USB chip for stable and straightforward communication with your computer.
• Customization Options:
  • Benefit: Designed with potential for client-specific customization to meet unique project requirements.

Technical Specifications:

• Control Axes: 2 (X, Y)
• Supported Software: GRBL Controller, BenBox
• Input Voltage: 12-18V DC
• Stepper Motor Drivers: Supports A4988 and DRV8825 plug-in drivers
• Stepper Motor Voltage: 12V
• Maximum Stepper Motor Current: 2A (1.5A recommended)
• Supported Stepper Motor Size: Typically NEMA 17 (size 42)
• Microcontroller: ATMEGA328P (with Arduino UNO bootloader)
• USB Interface: USB-CH340
• Limit Switch Inputs: Dedicated connectors for X and Y axis limit switches
• Servo Control Output: Dedicated connector for servo motor (pen lift)

Getting Started with Your 2-Axis GRBL Control Board:

1. Install Necessary Software:

   • Download and install a GRBL control software like Universal Gcode Sender (UGS) or GRBL Candle.  
   • If your computer doesn’t automatically recognize the board, you might need to install the CH340 USB driver (search online for “CH340 driver download”).

2. Connect Stepper Motor Drivers:

   • Carefully insert your A4988 or DRV8825 stepper motor drivers into the designated sockets on the control board, ensuring correct orientation. Refer to the markings on the board and the driver documentation.

3. Wire Stepper Motors:

   • Connect your stepper motors to the appropriate screw terminals on the stepper motor drivers. Double-check the wiring diagram for your specific motors to ensure correct connections.

4. Connect the Power Supply:

   • Connect a 12-18V DC power supply to the power input terminals on the control board, observing the correct polarity.

5. Connect Limit Switches (Recommended):

   • Wire your X and Y axis limit switches to the designated “X-LIMIT” and “Y-LIMIT” connectors on the board.

6. Connect Servo Motor (for Pen Lift):

   • Connect your servo motor to the “SERVO/Z-” connector. Typically, the three pins are for ground, power, and signal. Refer to your servo’s documentation for the correct pinout.

7. Connect to Your Computer:

   • Use a USB cable to connect the control board to your computer.

8. Configure GRBL Settings:

   • Open your GRBL control software and establish a connection to the serial port of your control board.
   • You will likely need to configure GRBL parameters ($ settings) to match your machine’s mechanics (e.g., steps per millimeter, motor direction, maximum rates). Consult the GRBL documentation for detailed instructions.

9. Send G-code:

   • Create or load G-code files into your control software and send them to the board to control the movement of your pen plotter or CNC.

Code Examples (Illustrative G-code Commands):

• Basic Movement:

  G0 X50 Y25  ; Rapidly move to X=50mm, Y=25mm
  G1 X100 Y75 F200 ; Move linearly to X=100mm, Y=75mm at a feed rate of 200 mm/minute
  

• Controlling the Servo (Pen Up/Down): Assuming your GRBL configuration maps spindle control to the servo:

  M3 S0   ; Pen Up (S0 often represents the minimum servo angle)
  M3 S180 ; Pen Down (S180 often represents the maximum servo angle)
  

  Note: The S values might vary depending on your servo and GRBL configuration.

Applications/Use Cases:

• Building custom 2-axis pen plotters for art and education.
• Creating simple CNC drawing or marking machines.
• Educational projects exploring CNC fundamentals.
• Automated drawing and design applications.

Package Contents:

• 1 x Upgraded 2-Axis GRBL Control Board for Pen Plotter & DIY CNC