Lightburn Not Recognizing Z Stop - Shapeoko Pro XXL

Help Please,

I have a Shapeoko Pro XXL (I just upgraded from an Shapeoko 3 XXL), on the new machine when LightBurn performs the home function the Z upper limit Stop / Switch is lighting but the SW is not stopping, it crashes into the stops and I have to hit the emergency power switch to prevent destroying my Z Stepper Motor Gears.

This does not happen 100% of the time, it is probably 3 out of 4 times. Sometimes it works just fine, but when it does not it is bad, it just keeps grinding when it hits the upper stop of the Z carriage. The X and Y switches all work just fine, it is just the Z stop.

This was not a problem on my Shapeoko 3 XXL, the upper limit stop worked 100% of the time.

I do not have this problem when using the machine for CNC machining, the X,Y, and Z switches all work flawlessly. It is only when using Lightburn.

I found that you have reached out via email and are getting direct responses there. We can update this post once sorted there. :slight_smile:

Searching and Following all things Shapeoko/Lightburn related. Please post this update, not a issue as of yet but may keep future questions. Thank You

Directly from Oz in an email thread:

I completely missed this:

M56P0
ok
N0 M5
ok
N0G1F300.0Z-10.0000
ok
N0 G4P0.005
ok
N0 G4P0.005
ok
$h
ok

$H is the command sent by LightBurn to home the machine too, but it’s possible that the M56P0 command that precedes it is altering the behavior somehow. If you could try typing M56P0 followed by $h in the console, that would verify it - if it homes correctly when you do that, that might be the key.

Followed with:

I was just suggesting typing the two commands into the console to see if they work. If they do, then adding them as a macro would be a start until we can change the software to accommodate.