Axis Motor size question

[tjones14]

I have descided on picking up a Joe's Hybrid 4x4 kit and using a g540 controller. However, I'd like to know what size drive motor I should be picking up. I know I'm going to need a "4 axis" system and slave one of the motors for the dual drive X axis, which kinda sucks because I'd like to add an actual 4th axis later, but meh, what can you do....

Anyway, back to what I was saying, drive motor size.. I was thinking the Nema 23 - 380 oz in would probably be enough torque, but should I go a little higher to make sure?

[jsheerin]

You could add a 4th axis later by adding a pci printer port card, a breakout board and another single Gecko drive and motor. That wouldn't be too bad cost-wise.

[Torchhead]

Or.......look at the BladeRunner AIO units that use the same GECKO drives and offer motor choices of up to 620 oz-in per axis and a snap in 5th driver/motor that can be hardware slaved and free up your A axis for rotary (with no more ports or BOB's). A lot of the proper motor torque depends on the final drive ratio. Fine pitched leadscrews will give you plenty of torque but poor speeds. The RPM of the motors with the 48V power will be in the 600 RPM range. Use that with the ratios of your rotary to linear drive mechanics. Keep in mind that stepper ratings are "holding torque" (0 RPM). As soon as you start spinning them torque drops off. How fast and how much depends on the motor.

TOM Caudle
www.CandCNC.com