More on Steppers (Servos rule steppers drool types need not respond LOL)

I stopped by today to visit a buddy I haven't seen in a couple years to buy a motorcycle trailer. He's been out of state taking care of his parents.
While I was there buying the trailer he handed me several other thing he was getting rid of.
Some screw in lifting rings, a roll around cabinet with a nice flat top that might be good for the small mill drill. Its old and heavier sheet metal than modern cabinets.
He gave me a few other things (He's de junking) including a box of small stepper motors. 3 are Nema 23 half tapped 2 phase 117oz, and 2 are nema 17 unknown force. Light duty stuff, but there was a Hobby CNC board and a variety of heatsinks in the box as well. I thought I might make one of those cheesy MDF frame gantries some guys make just for the fun of it with these.
Now I was wondering if anybody had any idea how to figure out what DC voltage and current setting would work well with these motors? I'm guessing 24-36 volts, and maybe 1-2 amps.
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On Mon, 17 Jan 2011 19:53:20 -0700, the renowned "Bob La Londe"

Modern circuits chop the power so you use a high power supply voltage on a very low voltage motor. Here are the specs on Sherline's motors, which are kinda midrange Nema 23s torque-wise, IIRC:
http://www.sherline.com/67127pg.htm
They are 2A at 3.2V, so would draw much less from a 24V supply with a chopper driver.
Measure the winding resistance and see whether it looks like an ohm or two.
Best regards, Spehro Pefhany
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Bob La Londe wrote:

24-36V will be fine, more like 3-4A. Small motors like that probably won't be good for a MDF router, that size would be more appropriate for one of the CNC hot wire foam cutters folks use for model aircraft airfoils.
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I meant made out of MDF. Probably put a rotary tool or maybe just a drag engraver on it.
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Bob La Londe wrote:

I know what you meant, but those steppers are still a bit small for that. I'm using 200oz steppers on my CNC plasma table (zero cut force), and 600oz steppers on my mini mill.
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What are you using for stepper drivers for those 600oz motors?
I'm running 382 oz on the Taig now, and I have a Max NC 5 fitted with the 280s I took off the Taig.
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Bob La Londe wrote:

I'm using a Bladerunner Dragoncut control (uses Gecko drives) for both machines (http://www.candcnc.com ). I swap cables at the controller to select which machine I'll be running and load the appropriate profile in Mach3.
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Makes sense. I am running Gecko G540 breakout and drivers in-one with with an external 48VDC power supply. I've got a couple 48VDC relays not yet hooked up for switching spindle and coolant. I like it a lot, but I'm not sure it can handle any bigger motors than the 380oz and provide full power. There is an outfit selling G540s on Ebay paired with larger steppers, but I'm not sure if they will produce full power or not.
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Did you notice that I am not responding?
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LOL.
Thank you Iggy. You gave me a good chuckle this morning. Don't panic. I have no intention of getting rid of the servos on the big mill.
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