This is my first CNC project so I'm not sure if this is a common problem or just my fault somehow. Here is my setup:

A small (dyna 2400) mill. I have 269 oz. in. stepper motors driven by a xylotex 4 axis driver. The driver is set to 1/8 microstepping. I have a single start 2.5mm pitch lead screw.

Here is the problem. I go to Mach 3 and go to the MDI screen and manually jog an axis. Specifically the x axis at this point. I have it set to step jogging and have the step size as .001". If I try to jog it one unit (.001") the stepper will attempt to turn and then it "cogs" back to where it was. It is similar in continuous jog mode. I'll make a jog of several inches and when it comes to a stop it "cogs" either forward or back.

It seems like it's not holding the microstep detents and is cogging back to one of the actual steps. Does this sound like what's happening?

In my motor tuning I have it set to 640 steps per. 200 actual steps * 8 for the microstepping * .4 for the threads per mm. I have the native units set up as mm as well.

If any of you need more information to answer please ask!

Is this a normal problem? Should I just abandon microstepping altogether?