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ZipSnipe
05-08-2008, 02:34 AM
How much stepper motor will I need to move my z axis if the weight of it is around 50 lbs? Would 495oz be enough?

Crevice Reamer
05-08-2008, 09:12 AM
How much stepper motor will I need to move my z axis if the weight of it is around 50 lbs? Would 495oz be enough?

Actual stepper power depends on whether you are driving it with a high enough voltage power supply. For example: If Stepper is rated at 3 volts, then you would want a power supply of at least 3x20 or 60 volts to get max power from it.

Driving such a stepper with a 24 volt PS would give lackluster performance.

What machine is this? Stock Acme lead screws or ballscrews?

CR.

ZipSnipe
05-08-2008, 03:24 PM
Haven't decided yet on the screws, for the z axis if ball screws work better, I,ll go with that, I would think that acme would be better for the z regarding the fact that it will be on the heavy side. The machine will be a cnc router

http://www.cnczone.com/forums/attachment.php?attachmentid=59233&stc=1&d=1210256786
CNC Router2r.jpg

But I,m thinking of having the spindle be a router(PortCable) but should I need to do metal in future projects , I plan to have the head be interchangeable.

skmetal7
05-10-2008, 06:44 PM
ballscrews are more efficient at transmitting force, over 90%. 495 oz/in should be plenty. have you thought of some kind of spring or gas shock to counter the 50lb mass?

Crevice Reamer
05-10-2008, 06:52 PM
How high (travel) and how fast do you want to move the 50 pounds? Ballscrews would give you rapid motion and easy maintenance, but would need a counterforce/weight to keep the head up with power off. Acme screws need checked and adjusted often.

CR.

ZipSnipe
05-10-2008, 08:08 PM
5 to 8 inches of z axis travel is what I'm wanting. And looks like ballscrews will be the coarse I will go. Thanx for the replies