I am new to CNC routers, so I hope my question is not too stupid. My CN will not go over 60in/min on any axis without stalling. I have no idea what I am doing wrong, so I am hoping someone can help me out. I know my little Ebay 3018 runs at about twice the speed of this beast. Here is my current setup:
NEMA 34 Steppers - 34HS59-5004S
1.8 deg/200 steps per rev
Stepper Driver - DM860T
Set to "8" for a total of 1600 steps per rev
60vdc power supply (57.4vdc out)
Lead screws are 5mm (.1969') pitch
Mach3 setup:
Steps Per - 8125 (.9) - I rounded down

The motors are tuned correctly. 1 inch is 1 inch.

I just read in a post the inductance of the steppers my be my issue. It is 11mh. However, when I run the numbers through a stepper motor max RPM calculator, I end up with a max speed of like 16 RPM which I know is wrong. When I do a little reverse math, it come out at about 253 RPM which seems to me much closer.

I guess my actual question is "Is the inductance of the stepper motor the issue?".
If so, what would recommend for replacement steppers?