Quote Originally Posted by masinecc View Post
How can i calculate what motor size i need for my gantry if i use rack and gear on both sides. This example is for ballscrews. Looking forward for your answer.
Backwards. Choose the RP size, gearing so that you have as a result normal rapid speeds with acceptable resolution. Then figure how many RPM you need in reality so you have mostly that in mind. Then you go back to the gearing ratio and gantry weight and from there you decide Nema 23 or 34.

Obviously as the RPM is the important part here cause most possible it will be well geared, then you finish with low impedance motors driven by high voltage.

And knowing that nema 23 motor driven at 70VDC moves a gantry max 50-60kg with gear 1:1 without problem at 10m/min via ballscrew, you can figure the motor you need for your case.