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static86
01-05-2013, 12:02 PM
I'm having an issue where the machine is losing steps while running toolpath and ruining my workpiece. Not sure if it is a Mach3 issue or a driver/stepper issue. It has happened 3 times on 2 different days, on 3 different toolpaths. I know the tool path is right, I have checked it multiple times in sim and the step loss seems to be random. The machine has run flawlessly at 100ipm, but running at 150, 180, and 200 ipm, it has lost step on. I am using the xulifeng usb motion card.

The first time it lost step in Y on a roughing path and was off +15.25 inches of where it was supposed to be cutting and ran full speed into the headstock on the guitar neck I was cutting.

The second time it lost steps in Z on a finish pass and cut too deep, was off 0.101 and ruined yet another neck.

The third happened shortly after the 2nd one, it lost step in Y again was off +4 inches and ran into the head stock on the new cut.

I'm not sure what is causing these random losses, so any help is much appreciated, Thanks.

awerby
01-05-2013, 06:32 PM
It sounds like it just won't go any faster than 100 ipm. What kind of motors are you using, and what power supply? Sometimes your power supply can be the limiting factor, other times it's the drives or the motors themselves.

But if you got this setup from http://www.cncdiy.org/ (which seems to be the source of the "xulifeng" board) then the maximum output voltage is 24v, which is pretty low, and likely to be your limiting factor. Most stepper motors work best and fastest when fed higher voltages. (about 25 times nameplate voltage is usually safe). So if you need to go faster, you might have to go to a different control system.

Andrew Werby
www.computersculpture.com

gio666
01-05-2013, 07:30 PM
I'm having an issue where the machine is losing steps while running toolpath and ruining my workpiece. Not sure if it is a Mach3 issue or a driver/stepper issue. It has happened 3 times on 2 different days, on 3 different toolpaths. I know the tool path is right, I have checked it multiple times in sim and the step loss seems to be random. The machine has run flawlessly at 100ipm, but running at 150, 180, and 200 ipm, it has lost step on. I am using the xulifeng usb motion card.

The first time it lost step in Y on a roughing path and was off +15.25 inches of where it was supposed to be cutting and ran full speed into the headstock on the guitar neck I was cutting.

The second time it lost steps in Z on a finish pass and cut too deep, was off 0.101 and ruined yet another neck.

The third happened shortly after the 2nd one, it lost step in Y again was off +4 inches and ran into the head stock on the new cut.

I'm not sure what is causing these random losses, so any help is much appreciated, Thanks.

There could be so many things cause it to do that. Your card is 48v .what is the stepping on drivers set to. 100ipm is extremely slow so i don't think you are pushing motors or controller to hard. Some thing most be happening with computer to cause it to do it at different drives and times . Are you running shield wire on spindle .Do you have prox switches on? Is spindle wire near prox wires or limit wires. You have a ground wire from spindle to z axis

gio666
01-05-2013, 07:38 PM
It sounds like it just won't go any faster than 100 ipm. What kind of motors are you using, and what power supply? Sometimes your power supply can be the limiting factor, other times it's the drives or the motors themselves.

But if you got this setup from http://www.cncdiy.org/ (which seems to be the source of the "xulifeng" board) then the maximum output voltage is 24v, which is pretty low, and likely to be your limiting factor. Most stepper motors work best and fastest when fed higher voltages. (about 25 times nameplate voltage is usually safe). So if you need to go faster, you might have to go to a different control system.

Andrew Werby
ComputerSculpture.com ? Home Page for Discount Hardware & Software (http://www.computersculpture.com)

I dont think it would be a good thing to run motors at 25 times 48v? Power supply would cost more than machine lol, its best to run motors at rated power. You can maybe up the amps .3 or .5 higher with out problem most times

109jb
01-05-2013, 10:13 PM
I dont think it would be a good thing to run motors at 25 times 48v? Power supply would cost more than machine lol, its best to run motors at rated power. You can maybe up the amps .3 or .5 higher with out problem most times

That isn't what he is talking about. A stepper motor has a "rated voltage" which if you apply that much voltage to the motor, the current flow will never exceed the maximum. For example, my steppers have a rating of 3.0V and they get run at 48V.

ihavenofish
01-07-2013, 09:26 AM
if the lost steps are genuinely random - they dont repeat in the same spot in the same program - then its almost definitely on the electonics side. mechanical / motor performance limits should be well above 100ipm, and should be repeatable. mach3 software issues should also be repeatable (like cv contouring bugs).


so, theres a number of possible things that can cause random stalling:

- interferance. if your drive psu is near the computer, drives, parallel or usb cable, etc this can happen. its especially likely on the big linear psus.

- pulse timing issues. mach3 timing in "motor tuning" could be set poorly, causing missed steps. alternatively, some pc's and parallel cards simply dont get along with mach3.

- hardware failure. bad drive, break out board, wiring short, etc.

since you have the usb board, parallel port specific issues are ruled out. i can imagine that the usb board could be the culprit, begin faulty. its also possible the board just doesnt run at higher speeds well, but ive not heard any other people complain about it (ive not used it myself more than a few minutes as a test).

gio666
01-07-2013, 08:39 PM
That isn't what he is talking about. A stepper motor has a "rated voltage" which if you apply that much voltage to the motor, the current flow will never exceed the maximum. For example, my steppers have a rating of 3.0V and they get run at 48V.

The power supply post was in joking.
The Voltage is more important to have right voltage for your drivers. what ever your driver voltage is ,But you can run most steppers a little higher in amps to get more torque

static86
01-08-2013, 10:55 AM
I've tried changing a few of the tunings but still no luck. It can run no problem at 300 ipm for over an hour and then the next tool path screws up within a few min. The errors are completely random.

I'm starting to think it is an interference problem. All the wires run in the same wire tracks to the machine, so it could be causing an issue since it seems to only lose step on Y and Z. The X wiring runs under the table and not close to the spindle wiring.

The 48v psu is about a foot away from the rest of the electronics/computer.

jassaf
01-08-2013, 11:37 AM
I've tried changing a few of the tunings but still no luck. It can run no problem at 300 ipm for over an hour and then the next tool path screws up within a few min. The errors are completely random.

I'm starting to think it is an interference problem. All the wires run in the same wire tracks to the machine, so it could be causing an issue since it seems to only lose step on Y and Z. The X wiring runs under the table and not close to the spindle wiring.

The 48v psu is about a foot away from the rest of the electronics/computer.

I then I have two suggestions:
1 - Run the file with the spindle off. (disconnected from the power supply)
2 - If the problem persists, then check the connection of all stepper motors. (There may be a bad contact).

Good Luck

DiaLFonZo
01-08-2013, 04:44 PM
I have random problem with that USB card too.
At the moment if i don't touch anything while cutting i am good.
But if i do touch the 3D screen in Mach3 while cutting.. it start and stop communication.. very weird..

static86
01-09-2013, 02:34 PM
I haven't had that issue. I've been able to zoom in on the toolpath and move the 3d preview screen while running no problem. The random step loss happens when I'm just watching the machine run, not touching anything.

gio666
01-09-2013, 04:41 PM
Yes try running with out spindle powered . You have the 2.7hp 220v and at high power it will trigger prox switches some times if they are to close . Also if not shielded it causes problems in stepper wire.
Also is it shield wire on steppers

static86
01-09-2013, 04:47 PM
If it was triggering the limit switches in the wrong place bc of interference, the machine would E-stop and I have shielded wire running to the steppers.

I'll try running with the spindle off to see if i hear any stepper stalling.

gio666
01-09-2013, 04:54 PM
If it was triggering the limit switches in the wrong place bc of interference, the machine would E-stop and I have shielded wire running to the steppers.

I'll try running with the spindle off to see if i hear any stepper stalling.

It happened to another person, took long time to figure out as switch just triggered then went back to normal and didn't even stay on light . Had to watch screen one day and seen light on mach3 for mill second than gone but enough to cause missed step

dsnaith
01-10-2013, 08:06 AM
If it was triggering the limit switches in the wrong place bc of interference, the machine would E-stop and I have shielded wire running to the steppers.

I'll try running with the spindle off to see if i hear any stepper stalling.

Is the shielding on all the stepper cables properly earthed? All earthing should tie back to one common ground point. Also, make sure the low voltage signal lines from the BOB to the drivers are well separated from the high voltage wires from the power supply to the drivers and from the drivers to the steppers. I twist my high voltage pairs from the p/s to the stepper drivers to minimise RF. Make sure the drivers and BOB are shielded from RF in a metal enclosure and the enclosure is also earthed back to the common ground point.

Dave.

Decibel Guitars
04-11-2013, 08:43 PM
This happened to me twice late in the day today. I packed it in and decided to do some research here to see if anyone had experienced this as well.

181525

It seems to be a similar problem, though it might only be my X axis that's dropping out. I'll take a look at where my power and communication lines are running in the control box, and i'll make sure all my shielding is properly grounded as well.


darren.

gio666
04-11-2013, 08:50 PM
This happened to me twice late in the day today. I packed it in and decided to do some research here to see if anyone had experienced this as well.

181525

It seems to be a similar problem, though it might only be my X axis that's dropping out. I'll take a look at where my power and communication lines are running in the control box, and i'll make sure all my shielding is properly grounded as well.


darren.

what is driver settings and mach3 settings
With weight of gantry and large spindle. X would stall a lot easier than Y and Z

Decibel Guitars
04-11-2013, 09:21 PM
I'll check my settings at the shop tomorrow.

There wasn't any documentation on how to set the DIP switches on the drivers, so I sort of took a shot in the dark. It's entirely possible I have them configured incorrectly.

I thought maybe I had my kernel running too fast, so I dropped it back from 45kHz to 25kHz and that didn't seem to make any difference, other than slowing down my max. speed.

gio666
04-11-2013, 09:24 PM
On is = 0 off = 1
Sw= 1 sw2= 1 sw3=0 sw4=1 sw5=0 sw6=1 sw7=1 sw8=0

- - - Updated - - -

I will be in Oakviille around 4 tomorrow if you are at shop then

Decibel Guitars
04-11-2013, 10:09 PM
Cool, I'll give that a try. Usually in binary logic 0 = off an 1 = on. ;)

I'll be around all day!

gio666
04-11-2013, 10:15 PM
Cool, I'll give that a try. Usually in binary logic 0 = off an 1 = on. ;)

I'll be around all day!

X drive will be set about half the y speed,

Decibel Guitars
04-11-2013, 10:19 PM
Ah, okay, so these settings are just for the X driver? What about the Y and Z?

Decibel Guitars
05-14-2013, 07:38 PM
Just to follow up on this, the issue wasn't anything software related. It was purely EM/RF interference from having the 48v power supply for the stepper motors in the same box as the breakout board and stepper controllers.

I pulled out the power supply and put it in its own box on the other side of a wall, and there are no more lost steps.

DiaLFonZo
05-14-2013, 07:41 PM
Did you have shield wires to the motors?
Shielded only at the ground in box

Sent from my HTC EVARE_UL using Tapatalk 2

Decibel Guitars
05-15-2013, 12:16 AM
All the wires are shielded.

ihavenofish
05-15-2013, 01:24 PM
Just to follow up on this, the issue wasn't anything software related. It was purely EM/RF interference from having the 48v power supply for the stepper motors in the same box as the breakout board and stepper controllers.

I pulled out the power supply and put it in its own box on the other side of a wall, and there are no more lost steps.

ahh, i had the same issue on my novakon. psu and pc/breakout all in one small box. once the mobo was separated out, it was fine.

gio666
05-17-2013, 07:07 AM
Just to follow up on this, the issue wasn't anything software related. It was purely EM/RF interference from having the 48v power supply for the stepper motors in the same box as the breakout board and stepper controllers.

I pulled out the power supply and put it in its own box on the other side of a wall, and there are no more lost steps.

yES, I knew that was the problem when i see box.