Cohesion3D LaserBoard Larger Laser Machine Installation Guide


If you have a larger laser machine, follow this guide for tips on how to get running smoothly.

For an overview of what to expect when installing the Cohesion3D LaserBoard into your machine, we highly recommend watching this Larger K40 Upgrade Guide by Teaching Tech. It is a great resource for getting started.

M2Nano Board

Identify your variant of board and wiring configuration in the Cohesion3D LaserBoard Installation Guide, then follow the instructions for replacement.

B1 Board

For the B1 controller variant, the board will be larger than the standard M2Nano, so some mount modifications and/or new holes may be necessary to install the LaserBoard. Use M4 Hex Standoffs on the panel and M4 screws to secure the board. If desired, refer to the Teaching Tech video above for ideas about alternative mounting solutions.

It also has a 6 pin power plug instead of the 4 pin one we are expecting, we will be covering this shortly.

Stepper Motors

If your machine has larger dimensions (greater than 300 mm x 200 mm) or uses stepper motors which are larger than Nema 17, review our Cohesion3D LaserBoard Buyers Guide for recommendations on external stepper drivers, the stepper driver cable pack and power supply brick. Also see the relevant documentation for Connecting External Stepper Drivers to your LaserBoard.


For larger machines, the bed size measurement will exceed the standard working area, so follow the steps for Setting Up the Correct Bed Size.

Review the documenation for Setting Up the Origin. Also, watch the Machine and Job Origin video for reference.

Home the machine, then use jog commands to move the head around to ensure it traverses properly. Measure the movement intervals to determine the exact amount of travel distance that you have/want and make note of the values in millimeters to input into the configuration file and LightBurn Device Settings.

If your machine homes to a different location than rear left, is jogging in the opposite direction, or the laser head is crashing there are some configuration changes to consider to correct it.

Updating the Config File

The below configuration parameters may need to be altered to dial in your settings. Values provided are starting points which should be tweaked to optimize your machine performance:

  1. Power off the C3D Board and remove the memory card. No lights should be on.
  2. Put the board’s memory card into your computer, using a MicroSD/ SD reader if necessary.
  3. Open the config.txt on the memory card using an editor such as Sublime Text. Do not use Notepad++.
  4. Decrease default_feed_rate (Ex: 2000 down to 1000 to test)
  5. Decrease default_seek_rate to slow engraving movement (not cuts), testing lower values incrementally until fine tuned (Ex: 18000, 12000, 9000, 6000)
  6. Increase current levels to dial in stepper motor performance (Changing Stepper Motor Currents on the LaserBoard)
  7. Decrease max speeds, testing lower values incrementally until fine tuned (Ex: 18000, 12000, 9000, 6000)
    x_axis_max_speed # mm/min
    y_axis_max_speed # mm/min
  8. Decrease acceleration to slow moves between cuts (Ex: 2000 down to 1000 to test)
  9. Update alpha and beta max to define your bed size:
    alpha_max - update based on the previously measured travel amount on the X axis
    beta_max - update based on the previously measured travel amount on the Y axis

    Note: The alpha and beta max dimensions entered on the config file will display in the prompt when setting up the laser using the LightBurn Device Wizard.

  10. Update the max travel (Laser Head Crashing into Gantry).
  11. Decrease the fast homing values, until fine tuned (Ex: 100 down to 50 to test)
    alpha_fast_homing_rate_mm_s adjusts the speed in millimeters/second (X axis)
    beta_fast_homing_rate_mm_s adjusts the speed in millimeters/second (Y axis)
    Similarly, if you have a motorized Z-table, the gamma values for the relevant parameters listed above can also be altered to dial in the configuration along the Z axis.
  12. Save the config.txt file on the memory card.
  13. “Safely Eject” or “Unmount” the memory card.
  14. Put the memory card back into the board and power up.

If you are still experiencing issues after making these configuration changes, you may be dealing with corrupt files. Reflash the SD card with fresh Cohesion3D LaserBoard firmware, make the necessary config file changes and resume testing.