Thanks Posix, I thought I might have ruined my motors. I am having problems with these motors. You know when you turn them you can feel the steps but it is smooth, well they turn smooth then sometimes you turn them and it is real rough to turn. It is not smooth and their is nothing in my gear boxes that can bind. I already returned the one motor now the other one is doing it. Have you ever seen this happen or do they do this from time to time.
Do you have the motors connected to the drives when you are doing this turning by hand and feeling the steps? Just connecting the two ends of a winding together will make it tough to turn by hand. Perhaps something in the drives has some windings connected together when it is in this tough to turn mode.
jeff beat me to it. usually the best way to isolate problems is to swap drivers around and see if you're getting the same problem. if it's still there but on a different motor then it's the driver that's causing it. if the problem persists on one motor with a different driver then it's the motor. with old motors usually re-wiring them cures alot of uneven running problems but it seems you're using brand new motors, right?
This happens when the power is off. I bought all my electronics new. The x axis motor was hard to turn at times. It made loud grinding noises when it started and stopped and never did run very smooth but the homeshopcnc was kind enough to replace it. The new one runs very smooth no problems. Now the y axis motor sometimes when the power is off and you turn it by hand is very rough but just ran it today and it ran smooth. I guess time will tell whether it is ok. I was thinking yesterday I was going to have same problem when I was turning it and did not turn smooth. But Thanks for your guys opinions. As long as it keeps working Im not going to worry about it.
Here are a couple of pics of my machine just got it together yesterday and was running it today. So far I am very happy with it.