Z-axis stuttering only on low speeds

I have an old Dyna Myte 2400 that I've reconfigured/hacked to work with a Gecko g540 driver. The Steppers and power supply are the originals that came with the Dyna. I've thought I had this thing working well for a while now but I'm getting a strange error.

When I try to jog the z-axis at a slow speed, the motor simply stutters. However this never happens if I use a high jog speed, only speeds under 2-3 IPM cause problems. There's even an intermediate range of speed where sometimes it stutters and sometimes it moves.

Most thread's I've seen talk about motors messing up at high speeds but not so much at low speeds. Is there some setting in the stepper config wizard I can toy with to address this issue?

Thanks!

You might want to try reducing your acceleration.

Also check your step and direction timing.

Rick G

I would echo the timing check

I've seen a couple instances of stuttering at low speeds on G540s with marginal step/dir timings
I would at least double the minimum timing specs, in fact for a parallel port driven G540,
there's no big cost with using 5 usec for all timings