[psimos]

Our Tormach PCNC1100 III very frequently stalls on G00 rapid move. This is set to 100 IPM. Is there a way we can override and slow it down to 70-80 IPM?

[SomeWhatLost]

wouldn't finding the cause of the stall and fixing it be a better course of action?
my 1100 s3 seems to rapid just fine at 100 or 110 or whatever its rated/set for...
so in theory yours should be able to also?

[nitewatchman]

Our Tormach PCNC1100 III very frequently stalls on G00 rapid move. This is set to 100 IPM. Is there a way we can override and slow it down to 70-80 IPM?

Something definitely not correct, electrically or mechanically. All axis or only one?

I would start by reseating all connectors, then check lube lines and axis for lube, then tightness of gibs.

nitewatchman

[psimos]

Thanks
I have adjusted and tightened the gibs few days ago but still stalls sometimes on rapid move.
I will check the electrical connectors and lube lines.

[tbaker2500]

Did it stall prior to tightening the gibs? Silly question I know, but they can be too tight.

[TurboStep]

Your question implies that you are sure you only have problems at rapid speeds. Is this correct?
As Nitewatchman has already asked, do you have this problem on all axes or with just one axis?
Has it been stalling since you acquired the machine or is this a more recent problem? If it's more recent, did you change anything at around the time it first started? Problems with gibs and/or lube lines can be confirmed by simply loosening one of the gibs a little to see if it improves on this axis. Obviously only for testing purposes!.
Do the axes appear move easily at lower speeds or do the motors sound like they have to work hard? On a series 3 all axes should be moving freely with no apparent straining.
Do you have a Tormach controller or do you use your own PC?
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[psimos]

Hello
Yes the problem occurs on rapid moves only. Most of the times the stalling is on the X and Y rapid moves. Couple of times the Z-axis stacked also. We bought the machine in 2012 together with the original controller. At lower speeds and machining feed rates I never had this problem. I have adjusted the gibs couple of times and the backlash seems to be ok. I have also added few EMC filters as per Tormach recommendations to eliminate possible noise on the stepper drives from induction loads (oil pump and coolant pump). No luck so far!
psimos

[Zetopan]

Yes the problem occurs on rapid moves only. Most of the times the stalling is on the X and Y rapid moves. Couple of times the Z-axis stacked also. We bought the machine in 2012 together with the original controller.

Since you are experiencing the problem on all three axes I would recommend that you look for a common source.
If you have appropriate instrumentation like a multimeter that can measure AC and DC voltages you could measure
your 240 VAC line voltage to ensure that the mill is actually getting 230 to 250 VAC. Likewise you could measure the
DC voltage on the main DC power supply capacitor (short thermous-bottle shaped, largest capacitor in the electrical
cabinet).

Similarly, try measuring the actual rapid movement rate on the X axis (where you have at least 18" of travel) and the
Z axis (a similarly large amount of travel). The X axis should be able to get very close to 110 IPM. Acceleration and
deceleration times at the ends of travel reduce the average to just below 110. The Z axis should average just under
90 IPM. Note that if the computer has ever been replaced, it is *always* necessary to rerun the calibration software
to get the interrupt rate to match the Tormach design rate, or else all of the positioning motor speeds will be wrong.
The mill and computer have no way to detect incorrect speeds, which is why the speed calibration program exists.

[TurboStep]

Hello
Yes the problem occurs on rapid moves only. Most of the times the stalling is on the X and Y rapid moves. Couple of times the Z-axis stacked also. We bought the machine in 2012 together with the original controller. At lower speeds and machining feed rates I never had this problem. I have adjusted the gibs couple of times and the backlash seems to be ok. I have also added few EMC filters as per Tormach recommendations to eliminate possible noise on the stepper drives from induction loads (oil pump and coolant pump). No luck so far!
psimos

Sorry for not responding earlier – have been away.
Shortly after rebuilding all 3 axes on my machine (that’s a different story) my PC died (just an old HP machine). After I got it all working again with a slightly newer PC model it sounded like the axes were binding, movements were straining, having to work hard. Rapids under the control of the pendent also stalled repeatedly. I never actually machined anything in this condition.
The problem sounded very mechanical so I assumed that my axis rebuild was somehow causing problems but I couldn’t find anything mechanically wrong. I then rebuilt an old PC (10 year old!) and it’s running perfectly again.
If your backlash is ok and the problem occurs on all axes then I’d look into the controller. There was a thread a while back where someone reported problems with the graphics drivers (I think) and that Tormach were able to provide a new version. I don’t recall what the symptoms were and I can’t find the post, does anyone else remember this? I did find a similar thread about problems with the audio drivers:
http://www.cnczone.com/forums/tormac...tml#post996114
and another that reported Adobe Reader to be a possible cause of problems:
http://www.cnczone.com/forums/tormac...ml#post1178931
If you have an old PC lying around I’d recommend running a fresh XP installation and downloading the Tormach PCNC software to see if you get a different behavior.
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