Plasma version of UCCNC and Pierce Height setting.

If you have a question about the software please ask it here.

Re: Plasma version of UCCNC and Pierce Height setting.

Postby Greolt » Wed May 08, 2019 12:19 am

Good to know

Thanks Balazs
Greolt
 
Posts: 229
Joined: Sun Sep 04, 2016 6:22 am

Re: Plasma version of UCCNC and Pierce Height setting.

Postby Greolt » Thu May 09, 2019 5:02 am

I have another related question.

On the default plasma screenset there is a button labeled "Delay"

My assumption is that this sets a delay before it will respond to up/down signals from the THC. Time set on general configuration page.

If this is correct then does this delay start from arc OK signal, or from when motion starts after pierce delay which we have provided in the gcode?

Next question,

I have never really understood what this setting means. "Control THC even if the THC on signal is not active"

Mach3 had a similar setting and I did not understand it then either. :)

Once I sort these two out then I will move onto what exactly do these two do "Enable THC anti dive" and "Enable THC anti down" and how and when to set them.
Greolt
 
Posts: 229
Joined: Sun Sep 04, 2016 6:22 am

Re: Plasma version of UCCNC and Pierce Height setting.

Postby beefy » Thu May 09, 2019 11:02 pm

Hi Greolt,

Delay starts from when the Arc OK signal is received (I recently asked the same question).

For an explanation of the Anti-Dive and Anti-Down, see the UCCNC manual in the M codes section (after G code explanations). See from M205 onwards.

An here is some info (not my words) I collect some time ago about "Control THC even if the THC on signal is not active" in Mach3 :

Normally in MACH if you are in RUN mode (code running) you cannot manually jog an axis because the code has control of the position. For THC one of the things it does is override that on Z (only) so the external UP and DOWN command will actually jog the Z while code is running X & Y/ If THC button is off normally it reverts back to not taking any jog commands except from the code.

The "Allow THC Moves...." is over in the Mill Setup because they decided to put in a feature that allows an operator to manually move Z while X $ Y are moving under code (a 2 axis operation where the depth can be manually changed) As it works out that exactl;y describes oxy-fuel cutting as well because it may need manual operator motion on Z while cutting.

The option should NOT be set for Plasma Cutting WITH the THC active because then you get dueling inputs AND it will move the Z the first UP or DOWN signal it gets and overrides the THC Delay. it creates problems during and right after the pierce where the torch will bounce wildly if you do not have the delay built in.


Not sure if UCCNC works any differently.

Keith
beefy
 
Posts: 449
Joined: Mon Sep 05, 2016 10:34 am

Re: Plasma version of UCCNC and Pierce Height setting.

Postby Greolt » Fri May 10, 2019 1:19 am

Thanks Keith

beefy wrote:Delay starts from when the Arc OK signal is received .

OK so we must add extra time to account for pierce delay if using this.

The option should NOT be set for Plasma Cutting WITH the THC active because then you get dueling inputs AND it will move the Z the first UP or DOWN signal it gets and overrides the THC Delay. it creates problems during and right after the pierce where the torch will bounce wildly if you do not have the delay built in.

I am a bit slow sometimes. This one confuses me.

In almost every plasma setup instructions I ever saw, the recommendation was to have this checked in Mach3

That seems to fly in the face of the above description.

It would be good to get Balazs take on this as it applies to UCCNC
Greolt
 
Posts: 229
Joined: Sun Sep 04, 2016 6:22 am

Re: Plasma version of UCCNC and Pierce Height setting.

Postby cncdrive » Fri May 10, 2019 8:18 am

I think that option can be useful for flame cutters where there is no arc ok signal. But for plasmas it is not really good to use this option, once because then the controller can't wait for the arc ok signal and because then the THC works even when piercing. With flame cutters often the Z axis is adjusted "by hand" using buttons on the THC up/down inputs and the operator is adjusting the height manually where this option can be useful.
cncdrive
Site Admin
 
Posts: 4695
Joined: Tue Aug 12, 2014 11:17 pm

Re: Plasma version of UCCNC and Pierce Height setting.

Postby beefy » Fri May 10, 2019 12:30 pm

Hi Greolt,

The purpose of THC Delay is to postpone checking/adjusting the torch height via THC, until the torch is at cutting height and cutting stable.

So normally the torch goes to pierce height, then turns on. Once torch ignition is confirmed via the Arc OK signal, then THC Delay starts. So yes, if you are piercing metal that requires a pierce delay, and thus the torch is sitting there for a little while blowing a hole, this has to be accounted for in the THC Delay period.

I normally have the plunge feedrate from pierce height to cut height as fast as the Z axis can move, no need to fart about once a hole is blown through, just get straight down to cut height and start XY moves. Perhaps on quite thick steel you'd plunge slowly as the torch pierce gets deeper, but I've never cut thick enough to need that. So basically I don't even account for the plunge time from pierce height to cut height.

I basically just add my pierce time (pierce delay) onto the time I think is enough for the arc to stabilize at cut height (I just use 1.5 - 2 seconds). So if my pierce delay was 1 second, my THC Delay would be 2.5 - 3 seconds.


Regarding what you said:
In almost every plasma setup instructions I ever saw, the recommendation was to have this checked in Mach3

I was surprised to hear that as I've never came across any recommendations to do that when plasma cutting and I started with Mach3. I've never had it checked for plasma work.

Keith.
beefy
 
Posts: 449
Joined: Mon Sep 05, 2016 10:34 am

Re: Plasma version of UCCNC and Pierce Height setting.

Postby Greolt » Sun May 12, 2019 1:07 am

beefy wrote:Regarding what you said:
In almost every plasma setup instructions I ever saw, the recommendation was to have this checked in Mach3

I was surprised to hear that as I've never came across any recommendations to do that when plasma cutting and I started with Mach3. I've never had it checked for plasma work.


Looked back at a couple of references and found it in the Proma and Robo3t setup guides. Sure I have seen it elsewhere too.

Not for a moment suggesting that makes it correct. Not sure why they recommend it. Just that they were places I had seen it.
Greolt
 
Posts: 229
Joined: Sun Sep 04, 2016 6:22 am

Previous

Return to Ask a question from support here

Who is online

Users browsing this forum: Bing [Bot] and 7 guests