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Davo242
31-12-2015, 07:10 PM
Wondering if anyone knows why my stepper motors keep stopping and starting when a program is running but in jog mode they run fine. Only new so Mach3 might not be set up ok.

Chaz
31-12-2015, 07:28 PM
Wondering if anyone knows why my stepper motors keep stopping and starting when a program is running but in jog mode they run fine. Only new so Mach3 might not be set up ok.

What code are you running through them? Can you show a vid of what's happening? Any details on the setup will be good too.

Davo242
31-12-2015, 07:55 PM
It's G-code. I won't be able to get a vid until tomorrow but will do asap. I have them set as is in the manual that came with them.

JAZZCNC
31-12-2015, 08:47 PM
Wondering if anyone knows why my stepper motors keep stopping and starting when a program is running but in jog mode they run fine. Only new so Mach3 might not be set up ok.

Not giving us much to go on here Davo we are not Mystic Meg's.? Could be lots of things.

Explain better exactly what happens ie: Does it stop completely or stop/start. On which axis and at what point of travel on machine, same place or random spots. When or where in the code, beginning, middle end.? . . . . Video better still.

Give details of the Motor tuning in Mach3 for each axis.
Give Info regards drive model and Micro stepping, PSU voltage, motor size/model.
Parallel port or external motion control.

Give some indication to size and type of machine.

Davo242
01-01-2016, 02:54 PM
170091701017011170121701317014

Chaz
01-01-2016, 03:03 PM
The vid is not watchable and the pics too small. Dont use the 'save locally' option, it makes the pics tiny. If you can get the vid on utoob, it will help.

Davo242
01-01-2016, 03:12 PM
https://youtu.be/rbJveQTkICA this is a link to a video of the motors

Davo242
01-01-2016, 03:23 PM
170241702517026 hope these are ok

JAZZCNC
01-01-2016, 10:09 PM
Ok well first turn the Kernal speed sown to 25000hz you don't need it that high. Going to high here stresses the parallel port.

Next the fact you are testing on the bench and not fastening the motors down will cause resonance which could be some if not all of the problem.

Also the Steps per setting how did you come to the figure of 320.? . . . . And What are Micro steps set to on your drives.?

Are each axis set to the exact same step per figure and tuning.? You must select the Axis on the side bar to correctly display for that axis and then save after every change.

Davo242
01-01-2016, 10:34 PM
Thanks for replying

Ok I will try fastening the motor to the frame tomorrow to see if this corrects the problem.

The steps per setting I have used is what was outlined in the illustrations provided with both the motors and drivers. The micro steps are set at 1/8. On my drivers this corresponds to off on off.

Yes I have checked each axis and they are correct.

I will try and upload pictures of driver.

Once again many thanks for your time and patience

Davo242
01-01-2016, 10:40 PM
1702917030
These are the drivers which are being used on the motors. They are set for 3.3 a

JAZZCNC
01-01-2016, 11:07 PM
The steps per setting I have used is what was outlined in the illustrations provided with both the motors and drivers. The micro steps are set at 1/8. On my drivers this corresponds to off on off.

Ok well 320 is ok but it should be worked out accourding taking linear pitch into account. With 1600ms then 320 would mean 5mm pitch. If your not using 5mm pitch and just bench testing then try 160 in steps per which would be like 10mm pitch and it's less work for the Parallel port to reach the same velocity.

This won't be your problem but it's a good starting point.

To help the parallel port you could also turn the micro stepping down on the drives to 1/4 (800ms) and set the Steps per 80.
Some times due to resonance you have to play with the MS to find best setting to match your motors. The quality of the drives plays a big part here and also how ridged the machine is. Hence why often Steppers don't work well on the bench.!!

EDIT: Ok well after seeing the drives then I'm not one bit surprised. Sorry to say this but they are Cheap nasty units which won't have much if any resonance handling capabiltys so it's no surprise motors are complaining.! They also often have slow electronics so it could be a timng issue.

One thing I've seen work before with these cheap drives is to toggle the Step low Active setting. (it's technical so won't get into why, just try it)
Also playing with Step Pulse Dir Pulse may be needed because the Opto's could be Slow so the Step pulse needs widening.
First try setting the Step pulse to 5 and Dir pulse to 0 and see what happens then if no change then toggle the Step Low Active.

Davo242
02-01-2016, 11:51 AM
ok i attached the motors to the cnc and still no change. i aslo have change the ms to 1/4 and 80. still nothing.
where can i find the step low active setting.

JAZZCNC
02-01-2016, 12:30 PM
ok i attached the motors to the cnc and still no change. i aslo have change the ms to 1/4 and 80. still nothing.
where can i find the step low active setting.

Here.

17052

Davo242
02-01-2016, 12:33 PM
ok i will try that. just wondering one thing i only have the demo mode on at the min would that be a cause of anything?

JAZZCNC
02-01-2016, 02:24 PM
ok i will try that. just wondering one thing i only have the demo mode on at the min would that be a cause of anything?

Only if your trying to run g-code more than 500 lines of code and it wouldn't cause stalled motors it would just stop moving.

Clive S
02-01-2016, 02:32 PM
ok i attached the motors to the cnc and still no change. i aslo have change the ms to 1/4 and 80. still nothing.
where can i find the step low active setting.As a matter of interest what Voltage is your power supply to the drives?

Chaz
02-01-2016, 02:34 PM
As a matter of interest what Voltage is your power supply to the drives?

I was just about to ask the same. Is the Voltage at the right level and 'clean'?

That said, it does feel like a Mach 3 config issue, look at the end of the vid, the DRO numbers look to pause and then unpause ...

Davo242
02-01-2016, 02:42 PM
its getting 24.4v

Chaz
02-01-2016, 02:43 PM
its getting 24.4v

Is that what the drives need? Sounds low to me but could be correct, not looked at any specs etc

Davo242
02-01-2016, 02:56 PM
what should the normal voltage be ? is there any way i could send u the maual for the drivers?

Chaz
02-01-2016, 04:39 PM
what should the normal voltage be ? is there any way i could send u the maual for the drivers?

There isnt 'normal'. I tend to see 50-80V usually. What does teh specification of the drivers say?

Davo242
02-01-2016, 04:45 PM
Introduction
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The TB1H stepper driver can actually operate within 12-50V(Peak Voltage) DC for different motors. Higher supply voltage can
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Davo242
02-01-2016, 04:49 PM
i was looking threw some set up videos on youtube and it was showing how to test the driver with mach3, my test showed that mine was pulsing to slow. but when i tried to up the kh it never changed. could this be a slow computer problem?

JAZZCNC
02-01-2016, 05:10 PM
i was looking threw some set up videos on youtube and it was showing how to test the driver with mach3, my test showed that mine was pulsing to slow. but when i tried to up the kh it never changed. could this be a slow computer problem?

Not so much slow computer but low voltage parallel port. It's common cause of problems on newer PC's and is most likely your problem if none of the other things I suggested have worked.

The easist/cheapist fix is to use PCI PP card but this can have problems because to all cards work with mach3.
Next option and by far the best is to get way from it and use external motion control card. This option is expensive thou.

Then you have the Drives.?? They are TB based drives and very very delicate things when it comes to voltage so don't what ever you do run them more than 36V or you'll fry them. 24V is safer but this does affect performance you'll get from the motors.

In all honesty they are Rubbish and not something I'd recommend building a machine based on but now you have them.!! . . . Well use them until they die.!
Trying to do CNC on the cheap 99.9% of time costs more than buying decent stuff and with a lot more hair pulling so not worth it.

There is another option you could try and is free and that is using Linux CNC. It may well work better with your PP than Mach3's driver does and end up costing you nothing.
I'm not Linux user so I can't help much on where or how but sure there will be others that can point you in wright direction.

Davo242
02-01-2016, 06:44 PM
its an old pc could be 7/8 years or older. is the motion control for the under powered parallel port ? im going to see about getting a newer pc made up on monday is there anything i should be getting in it that would be an advantage ie.. ports drives etc!!
im going to try the new pc on mach3 and if it still isnt working prop il try down loading linux cnc.

JAZZCNC
02-01-2016, 08:05 PM
its an old pc could be 7/8 years or older. is the motion control for the under powered parallel port ? im going to see about getting a newer pc made up on monday is there anything i should be getting in it that would be an advantage ie.. ports drives etc!!

I wouldn't waste money on buying a newer PC because it could be just the same. If your going to spend money and intend to use mach3 then buy an external motion control card.
External Motion controller will give you reliable system and higher performance. It will also allow you to use your Old PC because it takes much the work load away from PC. The parallel port is dead dieing technology best avoided.

I suggest before you go spending any more money that you do some research and learn more about Drives, controllers etc. It's all here on the Forum if you look. If not your going to waste money buying more rubbish or stuff that's wrong for your needs.

Which Motion controller depends on your pockets but if you can afford it buy one that uses Ethernet rather than USB. Komatis on the Forum sells Ethernet Smooth steppers which I would recommended.

Davo242
03-01-2016, 11:48 AM
Thanks for the advice jazz, I'm going to down load the Linux cnc and see if that solves any issues and if not then I think I will order one of the motion controler and see if that solves the problem. Does it connect to any Bob board? Once agin thanks for the advice.

JAZZCNC
03-01-2016, 12:30 PM
Thanks for the advice jazz, I'm going to down load the Linux cnc

Your Welcome and think you will have more success with linux cnc.

komatias
03-01-2016, 12:34 PM
Davo,

I too faced motor stalling like you show in the video on my first build. Looked through the cables, voltages step durations etc. I considered that it could have been my Gecko G540 driver so changed that to individual drivers..no improvement.upped the voltage.. Nothing..Never thought that the parallel port would be to blame and definately did not want to spend any more money on the problem.

Every time you lose a step the motors need to reaccelerate. All good and well when they have the voltage to boost them but not so good otherwise. This can leed to stalling as the rotation speed is not ramped but stepped. Hate to burst your bubble but if you are having bench test problems you will have hair pulling moments when you finally build the machine. I know I did even when the bench test was perfect.


Some more reading on the mach forum: http://www.machsupport.com/forum/index.php?topic=9943.30

In todays CNC world it seems that there is just no point in using the lpt unless you have a linux cnc system. Even then a lot of people use a motion control card. For example when i tried Emc with an Asus motherboard it would not pass the test the software performs.
Arguably the first and foremost frustration in any build log seems to be the issue of lost steps for whatever reason,( drivers, noise, lpt port) so eliminating it is money will spent in my opinion. Second will be backlash but that can be managed.

Best regards

George

Davo242
03-01-2016, 01:27 PM
Thanks George some good info on the link. The computer I am using is as slow as so I think that is the first port of call, then the smooth stepper which u supply if problems persist.