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Messages - reuelt

341
General Mach Discussion / Re: Mach 3 Threading Hangs
« on: March 31, 2019, 10:05:31 PM »
Sorry, I wasn't clear in my description of the signal I have.  At 500 rpm, it's a pulse that's about 5% duty signal.  By "square wave," I just meant that the signal is clean with square edges as if it had been shaped with a Schmitt trigger rather than the somewhat sinusoidal raw signal off an opto-sensor.  It's a roughly 6ms pulse out of about 120 ms that it takes the spindle to make a revolution at 500 rpm.

--

On a related topic, I don't understand why application of a UC300ETH with Mach 3 requires the use of a full A/B+Index input.  From Mach's viewpoint, what has changed?  Does the UC plugin actually change the Mach 3 trigger code/behavior?  If I understand the default Mach 3 setup instructions, the threading trigger normally functions with a single index input of 200us or longer.  As a related data point, Mach is happily taking the single input pulse and giving me the correct actual spindle speed.



OK
Thanks for your explanation.
Engineering-wise people don't refer a pulse to a "square-wave".
"Square Wave Waveform (by definition) is symmetrical in shape and has a positive pulse width equal to its negative pulse width resulting in a 50% duty cycle".

UCCNC - not good enough for lathe - turning. Does not support G32 only G76 in threading
MACH4 - Does not support G32 only G76. BUT UC300ETH does not support MACH4 THREADING using G76.
So the threading in MACH3 supporting both G32 and G76 are all MACH3 features and has not much to do with UC300ETH.
If it is me,
I would try to satisfy MACH3's necessary conditions even though an external motion controller is used
The people in Europe do not do threads based on TPI (which is a superior Imperial design)  That may be why CNCDRIVE people maybe trying harder because metric threads have very different inferior design. Rotate a 1.6mm metric thread 16 times - you get 25.6mm which is NOT = 1 inch. Rotate a 16tpi thread 16 times and you get exactly 1 inch.






342
General Mach Discussion / Re: Mach 3 Threading Hangs
« on: March 31, 2019, 05:25:43 PM »
...
So I would try to use simple pulse of 1 pulse/rev.
...

Yes, I'm using a 1p signal about 6ms long at 500 rpm.  The pulse is a clean square wave.
Sorry, I think a pulse cannot be a square wave. A pulse is like a short spike. You generate 1 spike when the headstock turns 1 revolution e.g. using a hall-effect device.
At 500rpm you should see 500 spikes per minute on the Oscilloscope and NEVER a square wave.

343
General Mach Discussion / Re: Bad Circles
« on: March 31, 2019, 05:13:41 PM »
Y-axis stalls when cutting circles but not when cutting squares. I'm using Vectric Aspire software. Vectric Aspire kind of blames Mach3 for the problem. Anything to that?
Try setting lookahead to 200 lines or even 500 lines (default of mach3 is 20 but default of Mach4 is 200) and turn on CV mode.
If you are NOT on demo copies of Mach3 (limited to 25,000Hz), the you can set the kernel speed up to 36000 or 45000 or 60,000 depending on your PC.
My Win7 32PC with Core I5 7600 can have kennel running at 100,000Hz with excellent result. So I increase my microsteps from 8 to 16 to get smoother curves.
Aspire postprocessor probably is now using many small straight lines instead of arcs to cut arc circles. You may need a better post processor (or settings) for MACH3 in Aspire.

344
General Mach Discussion / Re: Mach3 Pause is violent
« on: March 31, 2019, 12:21:39 PM »
"for example if I have chips in the drilled hole that need a little more time to clear out before tapping"

In system config | General config under Tool Change select "stop spindle and wait for cycle start".
You could put in T# M6 tool change in your gcode file to change from drill bit to tab bit.
Before you [cycle start] after changing tool, - you can clear the chips in the drill hole.

345
General Mach Discussion / Re: Mach 3 Threading Hangs
« on: March 31, 2019, 02:55:12 AM »
I think "cncdrive" was taking about some types of "Metric screw threads" used in Europe & elsewhere, that MACH3 doesn't support.
Mach3 should have no issues threading all Imperial Threads (based on TPI) and most common metric threads.
Correct me if I am wrong.

346
Link is here
https://www.machsupport.com/downloads-updates/main-programs/
It is called simply called Mach3 R3.043 although it is R3.043.0.062 patched against latest problem caused by Win 10 updates.  0.66 is known to have bugs.

Before you install Mach3 R3.043, please backup somewhere your XML profiles, your license file(s), any custom macros and add-on and plugins first.

Sorry, did you check whether the coupling between motor and shaft is not loose or broken?

Reuel




347
General Mach Discussion / Re: Mach 3 Threading Hangs
« on: March 30, 2019, 10:48:10 PM »
UCCNC (unlike MACH3) does use G76 (instead of G32) for Thread Cutting.

But listen to the horse's mouth...
"Post by cncdrive ยป Wed Jun 06, 2018 9:28 pm
We advice to not to use the UCCNC on lathes, because several lathe functions are missing for comfortable lathe usage.
With Mach3 the syncronous thread cutting is working, but there are a few bugs in Mach3 about the thread cutting which can cause issues with some type of thread cutting codes. (I can't remember at the moment which are the cases.)
With Mach4 the UC controllers can't cut threads. We have tried to implement thread cutting some time ago, but found out that it did not work at all on the Mach4 side, so we gave up on it.
Later it was reported to be fixed, but we could not find the time yet to make another try.
With the UCCNC the syncronous thread cutting works perfectly, but again there are missing lathe functions..."

348
General Mach Discussion / Re: Mach 3 Threading Hangs
« on: March 30, 2019, 06:46:13 PM »
Hi,

I just retrofit an Emco PC Turn 50 lathe under Mach 3 with a UB1/UC300ETH interface.  I'm using the original index pulse circuit from Emco and I get a very clean square wave about 6ms long at 500 rpm.  The index light lights up on the diagnostics screen when I turn the spindle by hand (the lathe diagnostic plugin appears to be incompatible with the UB1).  When the spindle is running, the index pulse light comes on erratically but a scope on the signal shows the pulses to be very regular.  I can see accurate actual spindle speed and can run feed-per-revolution moves just fine.  When I enter a G32 threading command, though, that block of code just hangs with no axis movement.

I've tried setting the debounce time from zero to the default of 100x40us and it doesn't seem to matter.  Also, have tried spindle speed averaging both on and off with no change.

Any ideas about where to look for the problem?

Thanks,

Mark

Since threading was written for the parallel port, could it STILL be expecting a slow pulse signal of only "1 pulse/rev"?
Art Fenerty said:
"when you consider Mach3 was designed for the printer port, and its
architecture is derived from the treacherous territory of Windows kernel mode, then it
will be understood more easily, why the design architecture, which has evolved over
time, must reflect the original printer port operation in terms of its internal limitations.
This means that the simple fact you are using an external engine does not mean you
will not necessarily have a limitation enforced by the original specifications of the
software."

So I would try to use simple pulse of 1 pulse/rev.

349
General Mach Discussion / Re: Moves in x direction before step down
« on: March 30, 2019, 11:14:01 AM »
Hi
I ran through your uploaded Gcode through a simulator, it is not showing that "it first moves over slightly in the x direction before beginning the Z level drop."

There is nothing wrong with this gcode file except that it your max. feedrate in this program is at 40 inches a minutes.
So check:-
1. If you are using parallel port, try to increase your kernel speed say from 25,000hz to 35,000Hz.
2. Check your x-axis coupling between the stepper and srew-shaft or gear has become loose or broken or not. Re-tighten all the setscrews at the couplings.
3. Redo your motor tuning and calibration making sure that you can run at fast speed without missing steps.

Reuel



350
General Mach Discussion / Re: Goofy forum layout
« on: March 30, 2019, 03:20:20 AM »
M4 Gcodes closer to Fanuc is a good thing.
People using MACH4 as a hobby may find employment in big organizations one day.
MACH4 Industrial version even better since you can create/customize Gcode to match a big Branded machine.

Point is when a user ask for help, it is quicker to give them the correct answer if we know which Program they are using without having to ask.

I am a member of the ORGANFORUM -  every member MUST list their hardware and software & version# in their signature. Same with some Astronomy Forums.

Asking just MACH4 or MACH3 is NOT so drastic when compared with some other forums.
it is just my opinion.