Z axis won't go down

So when I turn on the printer, the Z axis is for example at position 5, if I say to move 6 up, it moves, if I say to move down 6 it moves down, but I cant go down past position 5, if I manually turn the cart to position 3, it wont go down position 3, I am pretty sure it is a config setting and I don't know which one it is.

Another problem is the first time I home X or Y, Z axis goes up with weird noises, stops and then X or Y goes home, after that, if I home X or Y the Z won't move again, only for the first time.

Z will not go down until it has been homed.
The weird noises from the Z axis might be the setting in the config that sets Z max speed being too high (known problem with marlin)

Firmware might be thinking that your Z-axis is already at zero. You have to lower the z-endstop position until the nozzle is on the bed or change some firmware settings.
Try out the following procedure:
Move Z to the lowest possible point it can reach now ( by firmware not manually )
Then measure or estimate the distance from nozzle to the bed and send "G92 Z5" through a host program. ( when 5 was the distance you found)
Now the firmware believes the nozzle is 5mm above the bed and you can lower it further down.

Once you found the right distance, you can add the G92 Z4.567-line in the slicers start code, right behind the G28 command.

Edited 1 time(s). Last edit at 01/26/2018 03:00AM by o_lampe.