Re: [CAD_CAM_EDM_DRO] calculation of motor torque

Boris Maraž wrote:

>Hello!
>
>Somebody have formula to calculate approximately how much torque must have stepper motor to drive the router with 10mm/turn (or 20mm/turn) lead screw and to get speed around 30cm/second and the weight of moving arch over table will be around 15kg. Is it possible to do this with steppers or I must use servo motors.
>
>

Depending on the weight of the arch (gantry) and the type of leadscrew,
you can make
rough guesses. One big question is how fast you need that gantry to
accelerate to the
30 cm/sec velocity. The greater the acceleration, the greater torque the
motors need
to exert. If the gantry is over 50 Kg, or you need acceleration to speed
in less than
1/4 second, you are WAY into servo territory. If you can accept
acceleration in the
1 sec+ range, and the gantry is as light as you plan, it might be done
with modest steppers.
If you use ballscrews, the torque will be light. If you use an Acme
leadscrew,
I think you may have serious wear, not to mention the drag of such a screw
running so fast.

Jon