Im puzzled. My Z axiz will arbitrarily home on the wrong direction. It does it once in a while. Today it did a run that took 2.5 hrs no problem rehomed for the 2nd part and it homed in the wrong direction. Turned all off re plugged and then was fine. Pre heared the homed it all fine started the print and with cura it moved the head away and brings it in but it stopped moving z about 2mm from the table. Paused rehomed and it went in the wrong direction again. HW ramps with marlin. Any ideas?
My 1st suspension was the end stop wire disconnected somewhere but I checked it and found nothing. It occured to me it may be thenactual end stop but i have replaced it and it didnot before it was replaced. I also swapped stepper driver and motor.
You can try lowering the speed and acceleration for z.
What @guillermo_gerard said.
I had a similar problem with my #3DR. I made a video at 3DR delta printer almost working - YouTube which you might find interesting.