there are many reason: Material is not suitable for burning —-> Change material is easy to burn, like Kraft paper You forget focusing —-> focusing your laser by here Set cut speed too fast or set cut power too low at lightburn like below:
If still not working please contact us.
Stop working at middle progress / random stop / laser stops about 30 minutes
Don’t load grbl settings (as shown in the figure above), unless you know what you are doing. Changing the settings may cause your device to work abnormally. You can restore the settings by flash GRBL firmware. What you might need to know, About GRBL setting.