need help with stepper motor

[oldpoopie]

Hey all. This is my first post. I've just become entrenched in a CNC conversion of my HF mini-mill. I plan on using a ballscrew on the Z and I just purchased 4 brand new surplus steppers. They are nema 34 Sanyo-Denki type 103-845-1111, 4 wire. The only marking on the endcaps say 4.2v, 4.7a, and 1.8deg/step.

What I want to know is what will be required to drive these? What should I use for a power supply, and which stepper driver would be appropriate?

Thanks in advance for any help you could give.
-Justin

[CNCadmin]

I think you will have a problem having only 4 wires, you really want a 6 wire system.

[oldpoopie]

why 6 wire? With 4 wires, arent these motors bipolar? Most stepper drivers I've seen via google have been bipolar, like the zylotec.

[George McCre]

If you are wanting to build a drive yourself they have excellent schematics for bipolar and unipolor motors. At the very least there is a lot of very usefull information on the two. Zylotex has a three and four axis driver that is reasonably priced. I am sorry but I don't have the link handy. I am currently doing the research on building my own homebrew, a small one at first to make the driver boards for a larger CNC router.

[RotarySMP]

Given 4.2V 4,7A NEMA 34 bipolar steppers, you would appear to have motors which will be a very good match to the Gecko drivers. The Xylotex drivers are limited to 2.5A and 30V, and would be way under powered for these motors.

Are these single stack or double stack motors?

Go to geckodrive.com, and read the PSU white paper under the support menu. Actually read the whole stepper white paper. Marris put a lot of effort into this reference, and it is very informative.

[JFettig]

Yeah, the wiring is black white, red and green. Gecko drives are perfect, see if you can get ahold of a 80v power supply that supplys enough current for all of them.

Jon