Does the homing cycle fail immediately, or after moving some, then it fails?
Things to check…
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If the homing cycle fails immediately then the limit switches are most likely connected or configured wrong. (NO instead of NC, or visa-versa) check $5
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If the homing cycle fails after moving a bit, then the machine max size doesn’t match the steps/mm according to your axes drive mechanics. First check if you tell Lightburn to move an axis 10mm, that it moves 10mm. If not, recalculate for your steps/mm ($100, $101, $102). This would be because the homing cycle moves 150% of the axes max travel ($130, $131, $132) during homing, or until it contacts a limit switch. If the steps/mm is set incorrectly for you drive calculations, then the controller might think the machine has moved farther then it actually has. You will need to make you steps/mm calculations based on the drive type (lead screw, belt and pulley, etc) along with the microstepping setting on your drivers (1/2, 1/4, 1/8, 1/16, 1/32, etc) and the full steps per revolution of you stepper motors.
The setting of 80, generally corresponds to a belt and pulley drive system, with 20 tooth pulleys, 2mm pitch, and 1/16 microstepping, with 1.8 degree/step, 200 steps/rev motors). If yours is different, like different sized pulleys, different microstepping, different belt pitch, .9 degree motors, etc, 80 won’t be correct. Now, this is just an example. 80 could correspond to different settings, but it would be very specific.
If your axes are driven with lead screws, those usually have a much higher steps/mm number because of how it transmits linear motion. With the above microstepping and steps/rev stated above, your steps/mm would be 400 when using a 8mm (2mmx4start) pitch screw instead of 80, and that’s a pretty steep pitch for a lead screw.
Here’s a link to a nice calculator for motion control.
Even though you max travel is set way larger than your actual working size, if the steps/mm is drastically wrong, it will still fail the homing cycle.