Hello, there are many such problems already reported and the directions listed in those threads did not help. I am not what I am missing. I got the CNC 3 axis running with TB6560 driver board. X-Y runs as expected. Z-axis moves in one direction only.

Check 1: What if wiring may be wrong? - I swapped the Z-axis to Y-Axis and the same wiring works there. So the wiring seems to be not a problem.

CHeck 2: Parallel port low voltage - I ordered the PCI parallel port as my original had a problem. I probed through the pin and the voltage drop is 0 to 5 v.

Check 3: Motor O/P pin config - This config is the standard pins as X (2,3); Y (4,5) and Z (6,7). I played around the active low for step and dir pin but did not help. I would also attach the config xml file in the next post in this thread.

Check 4: Running Z- axis with out load - The stepper motor is Nema-17 and isolated the z-axis from all its attachment and ran it standalone. No improvement.

Check 5: Check for the faulty motor - I used the spare Stepper for another Nema-17 and see no difference.

All these checks were done following the tips given in the other threads. Now I am struck. Please let me know if there is any way that can fix.

Thanks for the help.

Attached is the mach3 configuration file.

Check 1: What if wiring may be wrong? - I swapped the Z-axis to Y-Axis and the same wiring works there. So the wiring seems to be not a problem.

Unless I completely miss understand what you are trying to say, it sounds like a bad stepper driver. Not uncommon with the TB6560  boards.

Mike

Thanks Mike. 
Sorry if that line is not clear. I swapped the Y with Z axis and tried to rotate in either direction. It worked.
You are right, there are lots of similar posts reporting problem with TB6560. Unfortunately, I read those, only got into such problem.
I will try today and if no success, then look for the better driver.

When swapping the Y and Z axis, are you swapping the driver and the motor (i.e. just swapping the driver inputs) or one component at a time?  There could be a mis-wired connection between the driver and the motor itself.  If you haven't already done so, swap the actual drivers between the Y and the Z both at the input from the breakout board (you are using one and not trying to run the drivers directly from the 25-pin connector, right?) AND the output to the motor.  If the symptom switches from one axis to the other, then it's the driver.  If not, check the motor wiring.

However, as was stated by TOTALLYRC, it's probably the driver as a mis-wired motor would usually have bad steps which you'd notice (usually by sound) or it could be a faulty breakout board.  Just something else to check before spending money on a driver if that's not the issue.

Stephen "Highspeed" Kruse

When swapping the Y and Z axis, are you swapping the driver and the motor (i.e. just swapping the driver inputs) or one component at a time?  There could be a mis-wired connection between the driver and the motor itself.  If you haven't already done so, swap the actual drivers between the Y and the Z both at the input from the breakout board (you are using one and not trying to run the drivers directly from the 25-pin connector, right?) AND the output to the motor.  If the symptom switches from one axis to the other, then it's the driver.  If not, check the motor wiring.

I changed the actual driver swapping between Y and Z. The symptoms switches. It is the driver that has the problem.
Thanks.