I got HobbyCNC 3 axis controller board.
I am using TurboCNC.

X, Y axis are working great. But for Z axis, it looks OK, when Z is increasing (UP). But Z is decreasing, it is slow (about half) and moved just about half. But TurboCNC considered it is moved full.

EX: I commanded to move done Z axis, 2 in. the axis is moving very slow and moved about 1in. But S/W thinks it is moved 2 in. But different direction move is normal. Commanding 2in, it moves 2 in.

What would be the reason? Please help me.

Try increasing the pulse width for the Z axis a little and see if that helps.

Try increasing the pulse width for the Z axis a little and see if that helps.

Thank you for your advice. I did not try that but, I resolved the issue.
I changed micro step 1/4 to 1/16. Now it works.

I will try your advice anyway.
Thanks again.

Also, manually turn your drive screw up & down, you may have some binding in the system in the one direction causing missed steps.