My problem is that I am trying to setup mesh bed leveling on my Root3Lite, but because my Z Minimum is set at the top of the Z axis, whenever I try and start the leveling process, the first thing that happens is the Z axis tries to go upwards (against the Z Endstop switch) and the whole thing comes to a shuddering halt!
This because conventionally, a CNC machine has its zero at the top of the Z travel (which is where I have my Z MIN endstop wired) - whereas a 3D printer has its Zero approx 0.2mm above the printing surface. To be honest, I don’t even have a Z MAX endstop (because that is the end I am cutting through).
Does anybody know how to stop the upward movement of the Z axis in Marlin prior to the actual execution of the bed level routine? As I do a G28 homing prior to running the bed leveling command, the Z axis is already sitting at its Zero point already, and although I have tried to find the unwanted negative movement command by searching through the Marlin 1.1.X. firmware, I have not been able to locate it.
Despite the awful noise of the toothed belt jumping teeth on the sprockets, the bed level routine does work as it should, although I have not made a complete mesh map up until now - at least until I can sort this problem out!
Any help or advice which may be given would be greatly appreciated..............
