Connect your Z-table into the Z axis header on the LaserBoard using the built in driver.
The external stepper drivers, accompanying cables, and the additional power supply are not typically required unless you are wanting to work with heavier projects, have a larger machine size/bed, or are using heftier stepper motors. For additional info: Cohesion3D LaserBoard Buyers Guide
If you are running a larger/heavier Z-table, or it uses larger motors, follow these instructions for how to connect the external stepper drivers: LaserBoard Connecting External Stepper Drivers
Possible Configuration File Changes
A few config file updates may be necessary to ensure that your table is calibrated properly.
Note: GRBL-LPC is configured by using the Machine Settings in LightBurn or via the $ commands in the Console.
For Smoothie, use Sublime Text as your Text Editor. With the power off, remove the SD Card and access it on your computer. Back up your current good config file and review the following:
Please note that some values are mm/min, mm/s or mm/s^2 in the config file and can cause issues if a value is entered improperly.
- Verify the gamma_steps_per_mm are correct. A value of 316.9 is a good starting place, but measuring the travel distance during testing will yield better results.
- If needed, increase the gamma_current. The board’s per driver max is 1.2 amps. Do not exceed the stepper motor max. Ensure the motors are not overheating after increasing. For more info: Changing Stepper Motor Currents on the LaserBoard
- Lower the z_axis_max_speed (Ex: 180)
- Ensure that your z_acceleration is uncommented and lower to between 120-180.
- Save your changes, eject safely, and put the SD card back into the board before powering everything up to test again.
Enabling and Testing the Table
Z Axis Control
- In LightBurn, enable the necessary option(s) for Z Axis Control under Device Settings. Review additional Z Axis Settings info: https://github.com/LightBurnSoftware/Documentation/blob/master/DeviceSettings.md#z-axis-controls
- On the main Cuts panel, the Material (mm) thickness sets the base Z height for your jobs. If “Relative Z moves only” is enabled in Device Settings, this value is ignored.
- To focus at the center of the material (primarily for cutting or defocusing), specify a Z Offset on the Cut settings window; otherwise, it will be focused on the material surface (primarily for engraving).
- For multiple passes, you can specify Z steps per pass per layer, if needed.
Test the Z-table
In LightBurn, use the “Move” tab or run commands from Console to test Z axis movement.
On the Move tab:
- Ensure that the “Distance” is set to a low number for the table to travel in mm (Ex: 10)
- Set the Z-Speed and increase/decrease as needed to test (Ex: 10)
- Use the Up and Down dashed arrows to move the bed vertically
Or on the Console:
- Enter G0 Z10 F60 in the text field and hit enter
- G specifies a rapid move
- Z is the axis and the number value is the position coordinates to move to
- F is the feedrate per mm/min. The example above (F60) is 1 mm/s, which is really slow
- Increase the F value to 120, 180, etc to test the feedrate
- Jog the bed up and down accordingly by alternating between Z10 and Z0