Hi TP,
I think it is actually me that is the problem. I did some further diagnostics last night and noticed that my digital I/O signals into, and out of, the KFLOP motion control board were fluctuating when the spindle was running. This was causing the KFLOP to see limit switch activation when there was none. That, of course, would stop the axes from moving as that is how I have things configured. However, Mach3 doesn't seem to know this, so I may have to write some C code that will pass such messages from KFLOP to Mach3. In the meantime, it looks this I have some serious RF interference that is likely the result of a ground loop. So, me and my multi-meter have a great deal of work to do!
I'll update this post when I find the problem and fix it, just in case there are others following this thread who would like to know the resolution. When I find one, that is.
Thanks for the support!
Cheers,
Jeff