RE: [CAD_CAM_EDM_DRO] Re: Grizzly G1006 Mill CNC???

> Let's do some math. With 1200 oz in stepper motors direct drive to a

ballscrew

> here is the force that would be developed. But let's de-rate the
> 1200 oz in motors at feed rate to 900 oz in
>
> 900X6.28X5X.9/16=1589lbs of cutting force. More than enough to damage
> something. I use 465 oz in nema 34 motors with my 5 TPI ballscrews and get
> over 200 ipm direct drive. I am using a G5404 axis driver.
>

Or people could look at the torque curves for various motors. All steppers
lose torque as the RPMs go up; I've see some 1200 oz-in motors lose so much
torque at 100 RPM you might as well brought the 450 oz-in and spent the rest
on beer.

For some situations low RPM might be ok, or you can always fiddle with
gearing (remember doubling RPM halves torque).

This is one case where you many not actually get what you're paying for. Or
think you're paying for.

Tony