Need some advice choosing stepper motors for a CNC milling ...
Plug in 150 RPM times 320 inoz and divide the result by 1351. the result is you need Watts mechanical at your feedrate. 4) The screw type matters. A ballscrew is 95% efficient while an acme thread is about 50% efficient for a 5 TPI screw. As TPI goes up, efficiency goes down.