Hi,
I have assembled several CNC machines and repaired them many times. For some reason I am having trouble connecting the motors to my 5-axis setup. The motor is a Nema 23 motor which is used to rotate the B-axis of the BC head. I am using this stepper driver.

So the problem is that I am not connecting it correctly. I tried about 30 combinations of A+A-B+B wires and red, black, blue and green motor wires. The combination keeps the motor pulsing and spinning properly but keeps the torque so low that I can turn it by hand without even trying. That's the main problem, it doesn't maintain torque.
I can get it to spin properly by jogging, but I can't maintain torque. I tried connecting the motor to the driver off the main cable with the same result, so the wiring is good. I've tried different stepper motor drivers with the same result. I've tried different stepper motors with the same result. A wire with red, green, blue and yellow wires works and maintains torque. After experiencing the same symptoms from the beginning, I changed the wire combination. Since I've tried so many wire combinations, I'm basically out of ideas. Many of these combinations work in a RPM gallop, but still have no torque.

 

I’m no expert but to encourage others to correct me I’ll have a go! I’ve never tried micro stepping a stepper motor but I assume they work by controlling current in the coils so that the output shaft is comfortable at an angle between steps. But this would mean that the poles are not aligned so it’s bound to reduce torque. If I needed precision between steps, and high torque I’d use a geared motor. In theory you could measure the angle with an encoder and use feedback control to adjust the coil currents but that’s rather complicated and expensive

 

yes, micro stepping reduces the torque .
You have tried different motors and drives so it maybe points to the signal source??
Also ensure it works on full steps
Also very important to set the correct constat rated drive current for the motor