What size stepper motor do I-need.

[CNC Visions]

Ball Screws, direct drive, .5"/rev, 48"X48" table, 2.2 KW water cooled spindle with 10" of travel. The machine is totally in pieces but I will post pictures as it goes back together. I'm replacing the rails and bearings so most of the machine is in tote boxes or stacked in a corner.

[Clive S]

Ball Screws, direct drive, .5"/rev, 48"X48" table, 2.2 KW water cooled spindle with 10" of travel. The machine is totally in pieces but I will post pictures as it goes back together. I'm replacing the rails and bearings so most of the machine is in tote boxes or stacked in a corner.

Ok then I take it you have read this earlier in this post from Jazzcnc

I'll save you a lot of headache and just say use 3Nm motors run at 65-70Vdc on 75-80vdc drives and you won't have any problems cutting anything.

Cutting speeds will depend on many factors like spindle power and tool material but 4500-5000mm/min wouldn't be out the way with 2.2Kw spindle using carbide tooling.

It might be better to keep away from direct drive and use belts and pulleys with a 2:1 reduction (that's what we tend to do this side of the pond) ..Clive

[CNC Visions]

I apologize for not reading everything, Jazzcnc's post would have answered my question.
I'm looking into your advice about getting away from direct drive. It would be much easier to optimize stepper motor performance with the ability to change the drive ratio. I'm not sure why this side of the pond prefers direct drive and drives on the wrong side of the road.
One of the reasons I joined this group was to look into different ways to do things.
Thanks to all for your help
Mike

[TheGoodGuy]

Hi!

http://www.ebay.com/itm/DC24V-Nema-2...item51cacf6f98
http://www.zappautomation.co.uk/elec...per-motor.html

Which type should I choose? They both have the same holding torque.

[JAZZCNC]

Hi!

http://www.ebay.com/itm/DC24V-Nema-2...item51cacf6f98
http://www.zappautomation.co.uk/elec...per-motor.html

Which type should I choose? They both have the same holding torque.

Well out of the two the Zapp motors are the better motors with slightly lower inductance and I know Gary's motors are good quality.!. . BUT whether or not these are the correct motors you should use depends on what your connecting them too.?

[TheGoodGuy]

I am going to use PoStep60-256 drivers and 48V PSU.

[Boyan Silyavski]

I am going to use PoStep60-256 drivers and 48V PSU.

the motors that they sell at the same place http://www.poscope.com/nema23 are the same motors that zappautomation or cnc4pc sells. That are the motors that most people drive at 70V with Leadshine drives.
I also am looking at that drive you say, plus they have new 8axis ethernet board. Just today wrote them a big letter asking them many things about the board and the drives.

What i am saying is that when looking at the pdf of the motors StepperMotorDimensionsNema23.pdf the torque curve driven at 60V or 40V is very same till 3000rpm, hence 4 motors can be driven by 2x35VAC toroid 500w, which rectified will give ~49VDC, which is very near the drive capability /50VDC 6A/ . One of the questions i asked is if really this drive could drive the motor with this setup, i expect they will answer me tomorrow.

What i say is that will be better than the motor you say.