[littleCNCjohn]

I have had an intermittent problem with my taig jamming while rapid traveling. I used to be able to rapid at 20 ipm but have slowed down to 15 and now just 12, yet I still ruin parts and break mill tools due to the problem. Oddly, I can jog at 30 ipm with all three axis simultaneously. That makes me wonder if Mach 3 doesn’t use the motor acceleration when rapid moving? At any rate, I have tinkered with the gibs repeatedly in a fruitless effort to address the problem, and now have them where I can just feel a little friction when turning the leadscrews by hand with the stepper motors removed. When it jams the motor still turns some, albeit slowly while making a squealing sound. Helping the motor by hand unjams it, allowing it to turn normally… It’s not always the same axis that jams either. Any clues?

Thanks,
John
:drowning:

[Fastest1]

Have you installed a different version of Mach lately? Any other changes besides reducing your velocity? Is your acceleration too high? I too occasionally run into a problem during a rapid that stalls or jams an axis. Looking back at the code never reveals anything. Just recently I ran a warm up wizard at 160 ipm for over 100 cycles of each axis (it does divide the velocity by however many axis are requested to move). Everything ran great, positional accuracy wasnt lost. I then turned my velocity down to 100 (mostly due to lack of trust in 160ipm rapids :-) and tried running a part I was making. During the rapid between slots it jammed for no apparent reason. Of course it junked the part. I then reran it in the air and it did it at the same place every time. Puzzled.

[littleCNCjohn]

No, I haven't changed Mach 3 (actually, looking to see if there is an update is on my "to do" list). It looks like rideredcr posted the same problem 30 minutes ago in this forrum ("Slow down rapid G00 in Mach 3?")

there Gar21 said
"Reduce the velocity setting in the motor tuning screen. The Velocity is your rapid (G00) speed.
There's also a rapid override slider that you can use to slow down the rapids, but you really should reduce the velocity."

I will try to look at my settings tonight to see what they are.

Thanks,
John

[lsces]

It sounds as if this is not so much a 'jam' but rather a 'stall' ... The machine is not physically sticking, but the stepper motors stop turning. You don't say if it affects all axies, or which controller you are using. The Microproto box should be quite happy with 30ipm and jog from end to end without a problem all day, but if the computer interrupts the pulse sequence because of some background activity this can result in a stall.

[littleCNCjohn]

That might be it, as the way how helping a knob that is squealing gets it turning correctly again. It seems as if the stepper motor is out of sync with the current pulses and turning it some corrects the phase.. I managed to get the Z-axis to do it momentarily yesterday, although it almost always happens on X or Y. I have a Micromill 2000 by MicroProto that came with the chopper and 200 oz-in motors. You are right that I can jog all three axis simultaneously at 30ipm without ever having a problem - I have only seen it happen when a tape file was running. I’ve run the software that checks your computer’s ability to provide signals, but that was before installing McAfee... I will check it again tonight! Thanks,
John

[lsces]

Kill any anti-virus and network! Has no place on a machine controller. Load programs via a memory stick.

[BAMCNC.COM]

Just simply turn up your pulse length, I'd try 5 in each step and dir. (those boxes on the right in motor tuning) Are you using sherline 1/2 stepping, if not there is your problem, that makes the pulse longer, then you can turn down your step/dir to 2 or 3 and have no issues.

Also I have mach set to 45khz

And I watch YouTube while drawing in Rhino3d and posting g-code, all while the CNC Taig is running... With ZERO issues, ever... Anti-Virus doesnt belong on the PC I agree, as it doesnt belong on any PC, but that's another subject...

Setting up your operating system correctly is the first step, it has nothing to do with the programs your using if you set it all up correctly. To get you started in this, simply google (SSD in "your operating system") this will help with some settings, then learn about "msconfig" and make sure your defragged... There are others, but your on your way to watching YouTube and rendering graphics while making chips.

[fretsman]

Just simply turn up your pulse length, I'd try 5 in each step and dir. (those boxes on the right in motor tuning) Are you using sherline 1/2 stepping, if not there is your problem, that makes the pulse longer, then you can turn down your step/dir to 2 or 3 and have no issues.

Also I have mach set to 45khz

And I watch YouTube while drawing in Rhino3d and posting g-code, all while the CNC Taig is running... With ZERO issues, ever... Anti-Virus doesnt belong on the PC I agree, as it doesnt belong on any PC, but that's another subject...

Setting up your operating system correctly is the first step, it has nothing to do with the programs your using if you set it all up correctly. To get you started in this, simply google (SSD in "your operating system") this will help with some settings, then learn about "msconfig" and make sure your defragged... There are others, but your on your way to watching YouTube and rendering graphics while making chips.

Brad, maybe you could possibly start a thread and teach some of us who are scared to death to run anything but Mach 3 all by itself? I would love to have that type of confidence as I'm in standard PC mode and stripped XP of everything just to be sure nothing fools with Mach 3.

I guarantee it would be a hot thread and my eyes would be glued learning as much as I can.

Dave

[BAMCNC.COM]

I may do that tonight... wait... Brad... What? Lol

Yeah, I'll get a video of me doing all that to help prove the point, but I basically assumed we are all using XP, that was my bad, so I will make sure to put that in the title. Good idea!

My 2gb of ram has been around 80% or so if I remember right and not one hiccup. There are so many different machine setups the thread will be a wild one I'm sure.

[lsces]

Bugger must not have posted earlier ...

2000LE controller needs pulse width set to 10 and 25khz kernel speed is more than adequate - even for the faster DSLS3000 controller. These are half stepping controllers so do not need high stepping rates out of the computer.

[xaruum]

I realize that you are running the dsls setup, however, if the taig defaults of 10u/25khz do not resolve your problem, you might want to test your PSU output. The symptoms you are describing are exactly what you would encounter if your PSU were starting go out of spec.

[lsces]

littlecncjohn is running a 2000LE which needs the 10uS pulse. If the internal HV fuse has blown then he would not be able to get 30IPM, the machine drops to around 15IPM max. It's an internal power supply and I have yet to see the voltage 'sag', normally the insulation just breaks down and the transformer has to be replaced.

[littleCNCjohn]

I think that the problem might have been that my acceleration was set too high. I reduced it on the X and Y axes from 10 in/s^2 down to 5 and then increased my rapid speed in a program that was repeatedly stalling at 15 ipm up to 30 ipm... and it ran just fine several times. Thinking back, I had increased the acceleration about the time that it began to sporadically jam. Stupid question, but Mach 3 DOES account for acceleration, right? Suppose I was machining a rectangular pocket with walls that are square with the floor. When the mill tool transitions from traveling horizontally to vertical motion, does Mach 3 “know” to allow for acceleration/deceleration? Any advantage to setting the acceleration higher? I have noticed that high federates (say 20ipm vs. 10 when doing shallow engraving) results in the walls being less sharp.

Since pulse frequency was mentioned, is there any advantage to increasing mine above the default 25kHz? I think that would only increase your maximum attainable velocity, right?

Good to know about the PSU – I will remember that for when it inevitably starts to go.

Thanks,
John

[BAMCNC.COM]

Well regardless, you will still be better off with a longer pulse, be it changing it, or instantly getting 20 out of 1/2 sherline mode.

[lsces]

Fun with corners ... That is on the DSLS3000.
On the 2000LE the difference is between 'absolute stop' and 'constant velocity' modes. The first will stop at each change of direction, while the second will try and smooth over the joins with more or less success.

[littleCNCjohn]

Stupid question: is there a way to change between 'absolute stop' and 'constant velocity' in Mach 3?

[lsces]

'General' settings window - around the middle if I remember right - but things have been moving around

[BAMCNC.COM]

Hit "tab" anything there? I can't remember.

[littleCNCjohn]

Thanks for all your help - that's good to know! 3 years into this and I'm still a noob

(group)

[Fastest1]

Thanks for all your help - that's good to know! 3 years into this and I'm still a noob

(group)

I agree wholeheartedly! I am glad for those who chimed in. I had read about how to adjust gibs etc as Bam was suggesting though I have always done it the lazier way. I will try his recommendations when I get off my butt and try to cut something. Always something to learn in this game.