Stepper Motor Control

I have 3 Bodine Stepper Motors that I bought new on E-Bay for controlling an Enco mill/drill. They are Nema 42s and are rated for 1125 Oz/inch. They are marked:

Type
42X2BEHD

Volts 3.6

Amps 6.1

INS F3 (dunno what that means)

Continuous Duty

200 Steps/Rev

I bought all three for $500. I hope they will work well for my machine. Can anyone tell me what kind of drivers would be suitable for this type of motor? Does anyone here have any suggestions/tips for mounting these to my mill?

Thanks much

Rick McNeely

Rick,
The most popular and cost effictive drives for this application are the Gecko drives.
Web site at http://www.geckodrive.com/
You need to be looking at the 201 or 210 drives for your application.
Once you get the web page open also click on support as there is a vast technical section there explaining about drives, power supplies etc.

John S.

Do you only want dumb drives to run the motors or do you want a control to run them? Check out AHHA.com for a nice control and drive package. Their stuff is aimed at the Bridgeport market but can probably give you info on running your motors with their system.

I give a second vote for gecko drives.

Im no CNC expert, but IMO, an AHHA system is "dumb" . With drives such as the gecko line to drive the motors in question...
You can use any PC capable of running software producing step /direction pulses to control either servos or steppers...no having to depend on proprietary controllers to keep the uptime steady.

There are a variety of very good controlling software out therethat is really cheap that can run circles around an integrated system...
(turbocnc comes to mind)that only costs $20, runs from DOS and can control up to 8 axes simultaniously up to a 28 Khz step rate, from a 486-66 + class PC.
Another awsome Windows controller that comes to mind is MACH2...which is a 6 axis(either mill or lathe) , 45Khz controller that runs from Windows XP/2000...@ $150 its a steal.
There are many many choices for controllers when using drives, and some are very advanced in concept.
back to the Gecko's...
best of all they run anywhere from $119-$180 US for each axis, not to mention excellent/super fast product support. Money well spent.

Integrated CNC for the small shop/ hobbiest (and some industial shops/ companies) is antiquated technology that is phasing out rapidly.

For me its a no brainer

so tell me about this intel 186 chip if you would please

I do believe cncnutz is right when he says( for the home shop pc based is the way to go)as you can't beat the price /perfomance they give with your older dedicated controllers. And if under $5000.oo is your buget there is Turner Tech and Ajax a little more money maybe not as fast I don't know but hard to beat for the price. My 2cents

The PC systems are cheap & do have a lot of power. For the home-shop, hobbiest, or a very tight budget, they could be a very good choice.

However, in a production shop I have to vote with Doug. I want buttons & knobs that are in the same place every time. I don't want to look away from my work to fiddle with a mouse on a screen.

The argument of more power in the PC system also is flawed. Many new controllers are bassed on a PC CPU that is built into the controller. They have the same computing power as the PC. Besides, unless you are supporting some high end calculations for high speed machining applications, or you are working with NURBS interpolations, you don't need that much computing power.

The only other argument for a lot of PC power at the machine is if you are combining CAD/CAM functions into the same PC that is running the machine. Again, possibly the right option for the home-shop/hobbiest.

In a production shop I don't want my spindles waiting on my programmer. He's working offline.

Didnt mean to step on anyones toes.And I dont have any personal exp. with the commercial production aspect of CNC.I go by what I sift through online.

I have read alot recently about large firms converting old outdated equipement to be run by a PC based system.
NOW..

I thought this topic was from a home shop/hobbiest point of view.
It didnt sound as if he was interested in spending $2500 on a complete AHHA system to me....Purchasing the steppers would have been a mute point in that case.

The guy asked what kind of drives he could use for his steppers on his mill......obviously(to me) this guys trying to do things on the cheaper side. All I did was agree with John, that Gecko's are the way to go, and politely suggested some software to compliment them.


Doug...you havent seen a PC based controller that offers a basic set odf canned cycles? Where have you been looking??

what do you base your comment about an intergrated system running circles around a PC based system? Have you tried a PC based system in place of your Intel 186 controller and found it to be inferior? Just curious.

I think you are underestimating a PC based system, personally.
I mean, to me it sounds ludicrous that a cpu labelled as 186(this equates to 25 Mhz of power), can run circles around a cpu of a dedicated machine PC of, say 2 Ghz, running nearly the same software and all the same japanese electronic components.
Is your system bus in your controller more advanced than today PC's, and able to transfer more data at a faster rate? If thats the case I want one..Ill just swap out the hard drive and add some more memory! ! !

What is it that makes your controllers system so much faster than my PCs ? ....aside from mechanical hardware..
Isnt it all the same inside, basically?..Just that your hardware is alot older than mine?

Id really like to know more about this Intel 186 chip now


[This message has been edited by CNCnutz (edited 07-31-2003).]

[This message has been edited by CNCnutz (edited 07-31-2003).]

Hey Doug
Check out machinemaster.com. I had one of these systems in my shop for about five years and it ran with out a lick or trouble the whole time. It aint fancy or flashy but it is a workhorse.
Fred T

The Intel i186 chip is/was a special purpose design geared toward embeded systems (eg. industrial controls, bank ATMs, etc.). Embeded systems are computers or controllers that perform very specific and limited tasks. Often, their CPUs utilize a very limited set of instructions like like a RISC chip.

It's inappropriate to compare the 186's performance and capabilities to a general purpose CPU (CISC) like those in your computer. A computer using the 186 as the main CPU would be a dog but in it's environment and performing the tasks it was designed for, I'm sure it would excel.

A good analogy would be like comparing your computer to a graphics card used like a computer. See what I mean? For general opeations, the computer will excell but when it comes to displaying complex graphics, the graphics card will excell.

Doug

I've never posted to this forum before and need some advise.

Where is a good place to look for used NEMA 42 motors? I need 2 or three.

Also, what should I look for in them (brand,model,specs.)?

Thanks for the advice guys,
Doug

PS: for home/hobby CNC using Gecko 201 drives.

How does Flashcut CNC compare to Gekko?

Thanks in advance,

Jim

This is an interesting thread. I think comparing a dedicated industrial controller to a home/hobby PC based one is an apples/oranges comparison. A few week's ago, I stumbled across some of the mill/drill conversion documentary's online & am considering converting the ol' Jet -16 in the garage...but I would never seriously consider it for production work. However, for the fun of it...and the ability to mill arc's & arc tangencies at home without dragging out a rotary table...it has it's attractive point's. Rick, there's quite a bit of PC based discussion at:
http://www.cnczone.com/forums/forumdisplay.php?f=221
http://www.cnczone.com/forums/index.php?

They lack features we need for quick turnaround of short orders. None I've looked at have even a basic set of canned cycles. When the situation changes with these low end controls I'll be the first in line since I have one machine needing a new control.

Doug,
Keep your eye on Mach2.
In the last month Art has impemented this program to understand the Modbus language used by a lot of modern PLC's. This will enable Mach2 to hand over to a PLC for tool changing, turrets and anything else needing a lot of I/O support.
Also in the last month he's brought in G52 which is like G54 but keeps the origin as 0,0 and doesn't move it as in G54.
All the other canned cycles are there and have been for a while.
This last week he's implemented open GL graphics for the tool path.
Have a look at this turn screen toolpath preview.
http://tinyurl.com/6qqj4

Recently he's also released a way for anyone to link to the program using simple VB script.
This has enables a few people to write conversation screens for this program.
Things like bolt circles, circular pocketing, rectangular pocketing, keyways and splines.
Another guy has written a simple engraving program for it, ideal for putting part numbers on.
Just fill in the blanks on the screen and it writes the code.

Subrountines have also been added, you can nest these up to 1000 deep and even call the same subrountine from inside the subroutine.

As the Chinese say "We live in interesting times"

John S.

Bear in mind that I'm new to CNC but can stepper motors be connected in either bipolar or unipolar mode?

Or, are they mutually exclusive?

Does anybody care to recommend a good brand stepper motor in a NEMA 42 size? What's you opinions, guys?

Doug

mccolld

yes unnipolar motors can be connected to bipolar drivers but not the reverse

Does anybody have an opinion on AC servos?

Most of the research I've seen has been on DC motors but I had a chance to scarf-up some Panasonic AC units over the weekend and the price was just too good to pass up.

Do they have application on a CNC router or Bridgeport conversion?

Doug

Not absolutely sure, but I don't believe anything in the low cost hobby class of drives is available to work with AC servos, or for that matter, with brushless DC servos either.

Does anybody know where I can get documentation on Panasonic AC drives and servos?

I didn't mention before, but I got the drives, too.

Some of the devices (motors and drives) are stepper. But all are AC.

Doug