Arc Ok won't work

[laki]

Beefy, I think he pressed the THC ON button on the N880 line.
The machine then continued without an ARC OK signal because THC was not active.
In fact, the plasma cutter does not work in the entire video clip and therefore the ARC OK signal is not active.

[beefy]

Hi Laki,

yeah you are right, I missed that.

Let's see if the OP responds to your earlier suggestion.

[cncdrive]

THC ON has to be active and the M3 also has to be active for the controller to wait for the ArcOK signal.
Otherwise if it was always waiting for the Arc OK then you could not even reposition the machine or in other words you could not move without cutting which would be not OK.

[beefy]

Hi Balazs,

and when the system is waiting for ARC OK, will any gcode after the M3 >> NOT << be run.

Example, over the years, with Mach3 I always heard "motion is paused" while waiting for the ARC OK signal.

However, it makes more sense that any gcode would be paused while waiting for ARC OK, because if you have say a pierce delay line after M3, (like G04 P0.5) you would only want that delay to start once the torch had fired.

[cncdrive]

All motion commands are delayed by the ArcOK signal. I think the dwell (G4) also, but you could verify it with simple testing. I'm not 100% sure now.

[Pyruu]

first of all thanks for all the comments.
i tried some code snippets today. All executed with THC ON & THC delay OFF


first one form laki:
N0100 M1031
N0110 G00 Z4.0000
N0120 M03
N0130 G04 P0.1
N0140 G01 Z4.1000 F3000.0 (Z axis up for 0.1)
N0150 M05
---> no break in Motion https://streamable.com/833a5p

then i changed the code a bit: Add z motion after m3
N0100 M1031
N0110 G00 Z4.0000
N0120 M03
N0140 G01 Z4.1000 F3000.0 (Z axis up for 0.1)
N0130 G04 P0.1
N0150 M05
---> no break in Motion https://streamable.com/kqzqii

the solution is to add an x/y movment after m3 like this one:
N0090 G00 X117.5000 Y225.0000
N0100 M1031
N0110 G00 Z4.0000
N0120 M03
N0140 G01 X117.6000F3000.0 (Z axis up for 0.1)
N0130 G04 P0.1
N0150 M05
---> break in Motion https://streamable.com/3ism7u

could someone please verify my tests

[beefy]

Hi Pyruu,

finally got around to doing some real life testing.

Everything worked OK on my system. Whenever THC was enabled the gcode halted at any X, Y or Z move and also did not run dwell gode (G04). I had to disable THC to allow the gcode to continue.

HOWEVER...........if you single step the gcode it's a different ball game. For example G04 runs even when THC is on.

I'm using development version 1.2113

[Pyruu]

Hi beefy
i installed the software version 1.2113 and import the old .pro file.
Got the same issue. I start the code with the on-screen cycle start button. After m3 only a movement will cause a break in motion.
G04 will cause a no break.
Do you tested the code from my previous post?

[jcoldon]

i saw that video something like that i run with my thc off what i do its i put a delay of 350 micro sec in the m3 spindel delay that way it wates 350 micro sec befor the torch moves
hypertherm torches have around 300 mili sec delay from the time the torch fire relay clicks . for some reason uccnc does not use arc ok when the thc is off . they should have a button to turn arc ok on and off that way dry runs still work

[xnaron]

I think I have come across the same or similar issue. I put a lot of detail and video in this thread viewtopic.php?f=4&t=2717