Remember Arc Lost position

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Re: Remember Arc Lost position

Postby Vmax549 » Thu Oct 27, 2016 2:46 pm

(;-) OK retesting that way WORKS.

That is a cool function.

Thank You(;-) TP
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Re: Remember Arc Lost position

Postby Vmax549 » Thu Oct 27, 2016 3:40 pm

HUMMM now if we could ONLY get you to program teh THC inside teh UC300eth chipset (;-) then you would have teh DIY PLASMA world by the tail.

But that might take up all the extra power and room in the chipset.

(;-) TP
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Re: Remember Arc Lost position

Postby cncdrive » Thu Oct 27, 2016 3:53 pm

Terry, the THC control was always coded into the microcontroller in the motion controllers, otherwise they could not work in realtime.
The arc signal lost is also detected by the motion controller and then the motion controller is who changes the target position to the arcOK lost position and then it just let the software know what is happening,
but the motion controller is who is in charge when controlling these things.

Maybe you thought about something else though, if so then I did not get the idea yet. :)
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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 5:01 pm

I think terry is implying intergrate thc within the uc300.... problem is.... analogue input not fast enough or not high enough bit resolution....

What about spi interface with the MCU for thc add-on board with higher analogue sampling (2 channel, 16 bit)....
Rob

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UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite.
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Re: Remember Arc Lost position

Postby Vmax549 » Thu Oct 27, 2016 5:40 pm

Yes Robert got it (;-) I meant to integrate teh THC sensing function from inside of teh UC300eth and not have an outside THC controller. There ARE controllers that can do that part (;-) CS labs comes to mind . You input teh Arcvolt values @ 50:1 ( not raw volts) into their analog in and teh controller handles EVERYTHING THC related.

Just a thought, (;-) TP
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Re: Remember Arc Lost position

Postby beefy » Thu Oct 27, 2016 6:02 pm

Robertspark wrote:Keith I had same thought about lost arc position and doing a touch off .... then I thought.... do you need to do a touch off? Given the torch should have been at the right cutting height when the flameout occurred.... then the torch is at the right height for an on the fly start....

Problem is... a 2m retract to start of line could be another issue.... unless you used that clever pcb plugin to correct for bed height (autoleveler).... and did a few touch offs


Good point about touching off at the flameout point BUT (always a but) if the plate has any warpage/lifting due to heat or it's lying on built up slag on the slats, etc, etc it's even possible that at the position which is the start of the gcode block the torch could end up dragging on the plate. Exactly the same the other direction too (touch off at start of gcode block) but worse, you would have the correct cut height at the start of the gcode block but you could end up with the torch nozzle dragging on the plate at the refire position.

I've seen a few photos of tables with LOTS of built up slag on the slats so I can see the potential for this to be quite real with a long gcode block.

Keith.
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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 6:09 pm

Robertspark wrote:I think terry is implying intergrate thc within the uc300.... problem is.... analogue input not fast enough or not high enough bit resolution....

What about spi interface with the MCU for thc add-on board with higher analogue sampling (2 channel, 16 bit)....


Sorry parallel discussions....

There was a post from Balazs on 6thoct

About the analogue inputs on the uc300... hence my suggestion about spi, and external high speed and resolution spi (monitoring the isolated 50:1 side... )

viewtopic.php?f=2&t=27&hilit=Analogue&start=30
Rob

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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 6:16 pm

beefy wrote:
Good point about touching off at the flameout point BUT (always a but) if the plate has any warpage/lifting due to heat or it's lying on built up slag on the slats, etc, etc it's even possible that at the position which is the start of the gcode block the torch could end up dragging on the plate. Exactly the same the other direction too (touch off at start of gcode block) but worse, you would have the correct cut height at the start of the gcode block but you could end up with the torch nozzle dragging on the plate at the refire position.

I've seen a few photos of tables with LOTS of built up slag on the slats so I can see the potential for this to be quite real with a long gcode block.

Keith.


Yeah, I've got a load of slag on mine, (15mm flatbar on edge...cut over length so it slots in and has a natural curve...). Cheap and quick to replace and move the slats around

The problem is... starting on the fly ... you don't know the height over the run-up distance... but with the autoleveler plugin.... that would set it up for you
Rob

Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite.
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Re: Remember Arc Lost position

Postby shad » Thu Oct 27, 2016 6:50 pm

I think we have to provide several methods for CutRecovery. For example "On the fly" or "SkipIHS" or "SkipPierce" or all in one.
Operator have to decide which way to use in the current situation. It is simply impossible to foresee all.
-- Andrew
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Re: Remember Arc Lost position

Postby Robertspark » Thu Oct 27, 2016 6:58 pm

shad wrote:-"On the fly"
-"SkipIHS"
-"SkipPierce"
-all in one.


Good point, at least we have the starting point with the very accurate arc lost position... the rest is macro of plugin work
Rob

Einstein ― “If you can't explain it to a six year old, you don't understand it yourself”
UC400eth, UC300eth, UCCNC v1.2105, Neuron Lite.
UCCNC v1.2105 Macro Manual
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