Installing Z-Table Endstops / Limit Switches
This guide can be used as a general starting point for installing endstops or limit switches on your Z-Table. Refer to your model specifications for more information.
First, ensure that you have set up your Z-Table and configured it accordingly: Setting Up a Z-Table
Connect the Endstops / Limit Switches
A bracket or mount may be necessary to attach your limit switch(es) to the table and there are several versions online to choose from.
Once mounted, connect the limit switch to the Z-MIN or Z-MAX, depending on where the endstop is physically located and/or which port it is currently plugged into. Use the Sig and End pins for the switches. The default is MIN, which is typically on top (or 0 on the Z axis), whereas MAX is typically the bottom (defaulted to 200 mm, but can be altered, depending on the height of your table). However, these values may be inverted.
Review the Configuration File
Depending on your set up, the min and max values can also be altered to account for a Z probe offset by entering a positive or negative number in mm (i.e., 10 or -10). For steps on how to properly remove the SD card and update the config file, refer to the initial Z-Table guide link above. Ex: Homing direction is set to home_to_min and your endstop is located on top, then you will need to set the gamma_min value. Inversely, if it is set to home_to_max, then you need to set the gamma_max value. Update the following variables in the config file as needed and make sure they are not commented out (remove the #). The limit enable should stop actions if the switch is triggered:
gamma_min_endstop 1.28^ # gamma_max_endstop 1.29^ # gamma_homing_direction home_to_min # gamma_min 0 # gamma_max 200 # gamma_limit_enable true # set to true to enable Z min and max limit switches
The configuration file is defaulted to home XYZ simultaneously. To change this, uncomment the homing order by removing the # at the beginning of the line. Adjust this value if the Z axis is not homing as expected. Enabling this should home one axis at a time, in the order they entered:
# optional order in which axis will home, default is they all home at the same time,
# if this is set it will force each axis to home one at a time in the specified order
homing_order XYZ # x axis followed by y then z last
Test the Endstop(s)
To confirm that motion and homing is working as expected, enter the following commands into the console:
- M119 to test the endstop
- G28.2 to test homing with all axes
- Or G28.2 Z to test homing on just the Z axis
More information: Testing Endstops / Homing Sensors on LaserBoard
Create a Homing Button for Z Axis
The default Home button on the Laser panel in LightBurn only has X and Y axes movement assigned. However, you can create a homing button which triggers the Z axis by using a macro.
- On the Console tab, right click an unused macro button
- In the Edit Macro window, enter a Button Label and populate the Macro contents field
- Option 1: Label as “Home All” for all axes and enter contents as G28.2 for all axes for the GCode command
- Option 2: Label as “Home Z” for only vertical movement and enter contents as G28.2 Z for the Z axis for the GCode command
- Click OK and the button will update in the console tab and can now be used to home the specified axes.