This is my first step in 3d printing.
I can't have the Z-axis working, when the motors are free they turn properly (and in the same direction), but when I connect the couplers to the lead screws (I've got some similar to these ones with 1mm pitch) and try to move the Z-axis the motor are just vibrating and nothing move. I guess there is too much friction for the motors, despite I can turn them by hand without much effort.
I tried to increase the current by turning the screw on the stepper driver (but it can turn indefinitely so I don't know when it is right, I try a bit further than with the neutral position).
Do you have any advice to help me solve this issue?