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      GRBL Configuration for LightBurn Optimization

      Introduction GRBL Configuration

      While many GCode-based laser machines are pre-configured to work with LightBurn, some models like Shapeoko, EleksMaker, X-Carve, and Acro systems may require specific adjustments to achieve optimal performance.

      Quick Configuration Tips

      1. Spindle RPM Adjustments
        Match the spindle max RPM ($30) to LightBurn's default (1000) or adjust the S-Value Max in Device Settings.

      2. Enable Laser Mode
        Set $32=1 for GRBL 1.1f or later to activate Laser Mode, eliminating pauses during power changes.

      3. Firmware Upgrades
        Upgrade older GRBL versions to 1.1f or later to enable Laser Mode and avoid excessive burn marks during engraving.

      4. Coordinate Systems
        If using negative workspace coordinates, enable CNC Machine in LightBurn's Device Settings.

      5. Unit Configuration
        Ensure GRBL reports positions in millimeters ($13=0) for LightBurn compatibility.

      6. Manual Homing
        For machines without limit switches, manually home the machine to use Absolute Coords or User Origin modes.

      GRBL Versions and Features

      1. Laser Mode ($32=1)
        Reduces pauses during power changes, improving engraving quality.

      2. Variable Power Mode (M4 Command)
        Dynamically adjusts laser power based on speed, ensuring consistent cuts and preventing over-burning in corners.

      Recommendation: Use GRBL 1.1f or later for laser operations. Older versions lack these advanced features and may result in uneven results.

      Accessing Machine Settings

      • Machine Settings Window
        LightBurn offers a user-friendly table to view, edit, and export machine settings.

      Ref-MachineSettings-1

      • Console Commands
        Enter $$ in the Console window to display the current machine configuration in plain text for direct viewing and editing.

      Guide-GRBLConfiguration-ShowConfig

      Configuring Machine Origin and Coordinates

      1. Identify Firmware Version
        The console displays a welcome message identifying your GRBL version when you connect the machine.

      2. Set Machine Origin

        • Home the machine using the Home button.
        • Use G0 X0 Y0 to locate the origin.
        • Machines with center origin require a workspace offset (e.g., G10 L2 P1 X-250 Y-250 for a 500 mm x 500 mm machine).

      3. Handle Negative Coordinates

        • Apply a workspace offset with G10 L2 P1 X-WIDTH Y-HEIGHT.
        • Reset offsets with G10 L2 P1 X0 Y0.

      Machines Without Homing Switches

      For manual homing:

      1. Method 1: Move the laser head to the origin position (e.g., front-left) with the machine off, then power it on.
      2. Method 2: Jog the laser head to the origin and use the G92 X0 Y0 command to set the zero position. Ensure $10=0 is set for this method.

      xTool Wi-Fi Upload

      LightBurn currently does not support GCode uploads via Wi-Fi for xTool machines. Development for this feature is ongoing.