[cr8zy1van]

So Gecko's site gives the following calculation for determining push:

In. oz. * TPI * π / 8 = lbs of push

According to this if I have a 380 oz-in stepper, driving a 10 tpi screw, I should achieve 1491.5 lbs of push (of course losses will result in a lower real world situation)

380 x 10 x π / 8 (or 0.3925) = 1491.5 lbs

Is this right? If so, I think I have been over buying steppers!

[RotarySMP]

Don't forget that this is holding torque. Look at the torque curve of the stepper and the torque falls off quite steeply with RPM.

This of course matches nicely with the torque requirements of a typical (non HSM) machine, where you need hi toque at low speeds to cut, and little torque at high speeds for positioning.

[cr8zy1van]

But still even at 65% of holding that comes out at 969.4 lbs of push. I expected maybe in the 300 lbs range. That should cut wood like butta.

[RotarySMP]

Are you using ballscrews (>90% efficient), or acme screws (~30%) efficient?

But yes, NEMA23 steppers can provide a surprising amount of oomph!