Rotating Ball nut

[paulus.v]

I have 2 x 12Nm nema 34's for the X (1 for each ballscrew), do you think I would get away with the rotating ballnut I found with my motors?. I know with them being bigger motors that the moment of inertia is greater than say a 4Nm, but I plan to drive them with 68V 8A drives.

From what I have read the 12Nm steppers could be a problem. Having high inductance you need to give higher voltage (maybe 150V) to run them to their specs. The torque will also drop fast with rpm. Probably you wont be able to get it moving reliably at 200ipm with decent acceleration using your 10mm screw pitch at 1:1 but I may be wrong.

Do you know the specs of your steppers?


I attach an interesting read. (1Nm=141oz-in)