stops cutting randomly

[kbenz]

Why does it do this? stops cutting, keeps moving, then refires. Did it 3 times on this file. I have always had this problem. Hypertherm65, CandCNC, sheetcam and mach

[beefy]

No idea, but I had mine just stop in the middle of a file, no fault warnings, etc.

I'd set up a new PC and see if you have the same issue.

What's making the cuts so ragged, looks like your machine has had too much caffeine.

Keith

[kbenz]

What's making the cuts so ragged, looks like your machine has had too much caffeine.

Keith

Old, cold rolled steel rails is my guess. Been wanting to upgrade to some linear rails.

[mike 1948]

I'll put in my 2 cents, Almost looks like you are cutting to slow and the torch is hunting for material to cut. That will give you a jagged cut and maybe cause lose of arc.

[jimcolt]

If something in the plasma cutter is causing the shut-off there will be an error code on the digital readout. Is there/ what is it? If no error code....then something in the wiring could have an intermittent connection (start signal wiring likely) or there could be a stop command in your Gcode file.....could be an input power wiring issue to the plasma.

Your jagged cuts indicate a mechanical backlash issue or a drive sizing / tuning issue as well.

Jim Colt Hypertherm

Why does it do this? stops cutting, keeps moving, then refires. Did it 3 times on this file. I have always had this problem. Hypertherm65, CandCNC, sheetcam and mach

[kbenz]

I'm not getting any error codes. It stops and starts again on its own. Not in gcode, I can cut the same piece again with no issues. I cut mainly 11ga. but when I do cut other material thicknesses I haven't had the issue. It may be because I don't do as much of it?

[kbenz]

I'll put in my 2 cents, Almost looks like you are cutting to slow and the torch is hunting for material to cut. That will give you a jagged cut and maybe cause lose of arc.

I'm using the book specs for speed and voltage

[acourtjester]

Coming up with a logical reason for this is hard but I think it is a program problem.
If it was a lost of arc the system would stop if caused by wiring or plasma unit problem.
Change in the thickness of metal you will change the parameters? in the G-code there for the program.
Any mechanical problem will not stop the plasma stream you may get a divot and this would cause the torch to dive and maybe shut down the system.

[kbenz]

Coming up with a logical reason for this is hard but I think it is a program problem.
If it was a lost of arc the system would stop if caused by wiring or plasma unit problem.
Change in the thickness of metal you will change the parameters? in the G-code there for the program.
Any mechanical problem will not stop the plasma stream you may get a divot and this would cause the torch to dive and maybe shut down the system.

But I can cut the same part without a problem?

[kbenz]

Your jagged cuts indicate a mechanical backlash issue or a drive sizing / tuning issue as well.

Jim Colt Hypertherm

Why does it do this? stops cutting, keeps moving, then refires. Did it 3 times on this file. I have always had this problem. Hypertherm65, CandCNC, sheetcam and mach

I did find some slop in the y axis

[acourtjester]

Forgot to attach this image
by you cutting the same thing with no problems was the just moving the table to a new spot and re-running it. Or was it latter after you reloaded the G-code???
Somethings never have a resolution!!!

[kbenz]

same part in diff spot on sheet. I see what you are saying now. I never run the same nest twice so I wouldn't catch that would I?

[bigbearzfan]

I had that problem with a TD. I did all of the troubleshooting in the Mach set up guide. Using a trouble light plugged in to the aux outlet and the plasma turned off. I would see the light flash for a second. I found the issue to be the PC. Replaced my old Dell with a refurbished HP with nothing but XP on it and I have had no more issues

[beefy]

I like to split the systems up to troubleshoot something like this.

Example, the PC sends the TORCH ON signal to the plasma cutter. So if the plasma cutter is turning off then re-firing in the middle of a continuous cut, either:

a) the plasma cutter is OK and the TORCH ON signal from the PC is going on and off OR

b) the TORCH ON signal is continuously there but the plasma cutter is switching itself off then back on (refiring)

Can you view the LED for the TORCH ON relay on you Candcnc PCB. Does it go off when the torch turns off. If it does you at least know the issue is on the PC / electronics side.

Keith.

[vmax549]

With a CandCNC system and random torch cutouts it is NORMALLY the PC generating bad signals that confuse the Multiplexing of the signals on the CandCNC side. When the signal goes bad on the PC side the torch looses signal and shuts off then the signal goes good again on the PC side and it refires.

There IS a fix for this on later systems you have to bypass the PC signals around the Multiplexer and go direct.

Call Tom and ask for help with it. On earlier units there is NO bypassing the signal. Later units have the bypass.

Just a thought, (;-) TP

[jimcolt]

The Powermax1250 will not refire as long as the start signal from your electronics stays active. The start signal must be released, then reactivated to get any Hypertherm torch to refire. This tells me that the start relay is dropping out....then for some reason re-activating. Gcode could be telling it to do this....or a loose connection in the wiring somewhere.

Jim Colt

[kbenz]

Thanks for all the replies. I have not been on here in a while. Have not been cutting much lately.

The problem is very random and I hardly cut the same sheet twice. I have only had it happen on 11ga. That may be because that is what I mostly cut

[tcaudle]

Have you done the "Lamp Test" covered several times on the CandCNC support forum? You will get a hundred different opinions because here because few understand how the outputs work on CandCNC controllers. You can cure this but you need to seek help from someone that has experience solving it. In most cases it either is something running in the background in Windows or noise getting into the PC and causing the outputs to "jitter" The lamp test lets you narrow it down. The cure is sometimes a different PC or a look at the position of the components and proper grounding of the table structure.

[kbenz]

Have you done the "Lamp Test" covered several times on the CandCNC support forum? You will get a hundred different opinions because here because few understand how the outputs work on CandCNC controllers. You can cure this but you need to seek help from someone that has experience solving it. In most cases it either is something running in the background in Windows or noise getting into the PC and causing the outputs to "jitter" The lamp test lets you narrow it down. The cure is sometimes a different PC or a look at the position of the components and proper grounding of the table structure.

Hello Tom. I was just reading about the lamp test last night on your forum. I will definitely try that when I get back to it. Thanks

[Jhart]

I had the exact same problem you are experiencing. Torch stopped randomly, then re-fired with no error codes on the PM45, or in Mach. It was consistent in that it always cut out for about a 3/4" length of cut. I could cut the same file on multiple occasions and the torch would cutout at different places, and a different number of times, each time I ran the file. I think this would rule out anything g-code related.

This began happening when I tried to update Mach 3 to use the DCC features. Never happened before this and hasn't happened since I switched back to the earlier version of Mach. This narrows it down for me, but I'm not smart enough to figure out a solution.

The sharpy in the attached pics shows the path the torch did not cut. Hope this somehow helps.

[acourtjester]

You did not say, is it not completing the cut form the pictures it looks like at the end of a cut the torch turned off.

[Jhart]

I may have screwed up the sharply line on the top photo, so it does look like the end of a cut. Both were actually in the middle of the cut and the pierce you see is where the torch re-fired and continued the cut. Sorry for the confusion.

[HammerDownJustin]

Pay attention in mach 3 when programing. I always try to zoom in and check cut paths. I have the same setup and have noticed when this happens I can open back up in mach 3 and zoom in with the cut width option on and there will be a small section uncolored..9 times out of ten you can move the start point a hair over and it will all go green and cut perfect.

[kbenz]

Talked to tom. Did the lamp test. test showed noise(ground). Ran an isolated ground with isolated receptical . Moved pm65 to other side of table away from electronics. grounded table. Torch cable is not run with cnc cables. Still doin it

[kbenz]

said I must be getting noise through the parallel port. Time to find another computer