[pzr]

Hi

Few weeks ago I bought following set from Longs motor on Ebay:

http://www.ebay.co.uk/itm/2809598289...84.m1439.l2649

So Ive got:

* Nema34 1600 oz-inch steppers - with 4 wires: A+ red, A- green, B+ yellow, B- blue
* Dm860A Microstep drivers
* Power supply 350W 60V 5.85A
* Break out board with parallel cable connected to the laptop

I'm using Mach3 (demo for now) on Windows Xp Pro to control it.So far I wired only 1 axis using 1 power supply, 1 driver, 1 motor etc I did it according to the file you can find in attachment I set microsteping to 1/10 and later 1/8

And here is my problem: The engine runs very rough and tends to jerk and stall. Changing Velocity and Acceleration in Mach3 doesn't help - believe me or not I've spent many days (and nights) trying different settings.To eliminate possible problems I've used other 3 motors, power supplies, drivers etc - problem still the same .So there is no problem with the set itself - I reckon.
I run mach3 Driver test but I don't know what to think about it - mean during the test most of the time program says: system stable,excellent and occasionally pulse too slow or too fast - but there is no test results on finish like on any other test programs - so I'm a bit confused in this matter too.


Here is a YT link which shows how the engine spin:

Nema 34 stepper motor problem - YouTube

Is there any mistakes or wrong wiring you reckon I made ?? I have no more idea how to set it up to get better result

Any comments will be helpful. Thanks Yaz

[alan_3301]

sounds like you need to adjust the driver timing settings. should be options for step pulse length. make them higher.

[LeeWay]

Okay.
For one thing you do have acceleration set way too low. Or the timing in the laptop isn't responsive enough.
When you get off the jog button, motion should cease.

I don't know anything about those drivers either. Have you tried setting the step and direction pins to different active states?
If not, give that a whirl.

[ger21]

I run mach3 Driver test but I don't know what to think about it - mean during the test most of the time program says: system stable,excellent and occasionally pulse too slow or too fast - but there is no test results on finish like on any other test programs - so I'm a bit confused in this matter too.

What you want to see when you run the driver test is a flat line, and the pulses per second remaining very constant, ideally around plus or minus 10 pulses.

Do you have the motor mounted to a machine? If not, you'll probably find that it will run better when mounted to a machine?

What kind of a machine do you plan on using this motor on? It's very likely that you're a victim of buying too much motor. Large motors like that will often perform far worse than smaller ones.

Another user here purchased a similar motor and drive as you a while back. The first thing he did was replace the drive with a Gecko drive, and immediately got smoother motion and much higher speeds. The biggest performance improvement, though, came when he replaced the 1600 oz motor with a 400 oz motor.
The smaller motor outperformed the larger one by a factor of 4-5 times.

A motor like the 1600 oz that you have works best moving very heavy loads, at low rpm's, 300-500rpm max.

[LeeWay]

Right.
I concur with Ger there.
I run Nema 34's 1200 oz on my mill. I do use Gecko 203V's. Very strong and efficient for my mill, but they would not do as well on my router.

[awerby]

While I second the good advice you've received so far, I thought I'd point out that it's not recommended to run Mach3 on a laptop. There are power-saving settings and interruptions inherent to them that desktops don't have, which you can't get rid of. So when you get the new drivers, get a different computer to run them as well, either with a parallel port or a USB controller, like the Smoothstepper.

Andrew Werby
ComputerSculpture.com — Home Page for Discount Hardware & Software

[109jb]

I look at your video and the wires from the stepper to the driver look like the colors are in this order red-white-yellow-blue.

Then looking at the wiring diagram you supplied, it looks like it should be red-black-white-green with the blue and yellow connected to each other and the brown and orange connected to each other.

Also, the motors have 22 mH inductance, so using the gecko formula, the motors really want about 150 volts!!!!

[pzr]

Thank you for all your replies.

Started to thinking the problem is with my laptop or driver settings. When I run the driver test, the pulsing is all over the place - far away from straight line
It varies between too slow, excellent and too fast etc
I have tried every possible settings for the parallel port in the bios, but the results are the still same

Checked the motor wiring with multimeter and seems to be fine - I've got motors with for wires - I know that sketch shows connection of 8-wires motors.

My next step is to try use PC instead of laptop and see if that help - will post results as soon as bought spare PC - mine doesn't have parallel port

About the motor sizes.. I'm going to built a router 2.5m x 1.6m. going to cut solid wood (oak) on that. I'm carpenter and this is my first ever CNC project, so I was thinking - bigger is better Now I see I should go for smaller motors - especially for Y and Z axis. Would Nema23 be ok with this size of router??

Once again thank you all for your help - really appreciate it!

[LeeWay]

I think for that size machine they will do fine starting out. You can use some gearing on them to get increased speed if needed.

I run several laptops on my cnc machines, but they are all the older IBM R40 type.
I have only tried one newer type and didn't have usable results with that one.

For the R40's, I pretty much have to throw out the baby with the bath water. I strip it to bare bones XP only. I keep several spares on hand ready to step in anytime.
I am working on a new plasma cutter though and had to spring for the correct desktop with both a parallel port and a serial port on board.
Luckily I found a refurbished unit for $99.00.
Most of my laptops cost anywhere from $75.00 to $125.00 off Ebay.

Don't know how difficult it is over there to find a PC with a parallel port on board, but you can also add a port or two later if it is needed.

It all could very well be the timing in that laptop. Good luck with it.

[Jan Rune]

There is no such thing that you cannot use a laptop for Mach3. Disable ACPI in bios and everything else is just software switches. On some Dell, HP and other manufactors with there own BIOS this myth might be true.

[LeeWay]

There are some that simply will not work for sure. I think some model Dell's.
The other one I tried was a Toshiba Satelite. Maybe an 2004 model, so it wasn't new even when I tried it.
I know I found one that does work and they happen to be cheap and plentiful.
No muss, no fuss.
These would not work with regular BOB's.
All my BOB's get a 5VDC to operate the signals from a seperate power supply.

[Nitrografix]

I was having trouble like that with the longs kit I bought and the problem was that I was getting my 5v from USB, I used a wall wort and then just bought a 5v power supply about a week ago it's fine after that

[Mdixon]

I had this sort of issue and Longs suggested all sorts of settings in Mach 3 that seemed to sort out this issue.
I can supply what they sent..... If I knew how to attach a file!!!

I have a different issue - The motor does not fully "lock" on power up. It will then not work. After a while there will be a "singing" noise from the motor going back to the DM860 Driver, and the motor will "lock". It will now work after a fashion - but will not take any real acceleration or speed.

Mary Chen does not seem to want to answer any e-mails about this

I have 3 motors and this is the only one that will not perform

Any Ideas welcome
Also if you can tell me how to upload the PDF Longs sent me on Mach 3 Settings - I would be grateful

[mrbigde]

Hi, I have the same problem with dm860 driver and 860oz.in nema34 motor..stalls and missing steps low rpm. Can't seem to find what I'doing wrong.....Maybe you should try a desktop pc It might becase you are using a laptop. Not sure. Me I have tried many wire configurations and steps setting on thhe driver but still can't get feeds higher than 50 ipm on my cnc using a 5mm pitch ballscrew. Seem like there's no torque and no good rpm from the stepper. Is it the driver switch micro steps or mach3 or my motors are to weak. I don't know anymore. If you find a solution let me know. :drowning: