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Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 11:55 am
by kawarider
Option curve converted is not in my post. As post I use Mach3 with scriber. THC is Neuron Lite. Any suggestions about the post? Neuron and UCCNC works like a charm, it is only this little thing.

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 12:01 pm
by Robertspark
This may be worth a read too.... Won't fix your problem though but may help you understand it's cause maybe
viewtopic.php?f=4&t=1657&p=12813&hilit=Corner+error+max#p12813

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 1:14 pm
by tõnisson
Check your post processor editor again, there should be a line with "minArcSize". Use the search function.

If that does not help, maybe you can copy all the text from your post file to the forum.

-------------------------------

Copy-Paste from your g-code

N9760 M11.1 (THCON) (On all corners)
N9770 X964.3447 Y1746.9392
N9780 G03 X964.3500 Y1747.0000 I-0.3447 J0.0608
N9790 G01 Y1802.0000
N9800 G03 X964.3447 Y1802.0608 I-0.3500 J0.0000
N9810 G01 X955.1623 Y1854.1367

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 3:54 pm
by kawarider
Here is the post.

Will take a look on your link now Robert, thanks.

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 4:00 pm
by Robertspark
You may want to change this to one of the sync macros

thcOnCode = M101
thcOffCode = M102

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 4:02 pm
by Robertspark
You may want to change this one to say 2mm.... I think you will struggle to detect an arc with plasma having a radius less than 2mm

minArcSize = 0.2 --arcs smaller than this are converted to moves

Re: jerky movement plasma table

PostPosted: Thu Apr 16, 2020 4:08 pm
by Robertspark
You may want to add this to your post

post.SetOptions(post.ARC_SEGMENTS

It will break a circle into segments.... It helped me out with a problem I had a while ago

There is a bit of waffle here
viewtopic.php?f=16&t=2265&p=19653&hilit=post.SetOptions+post.ARC_SEGMENTS#p19653

Plus sure there are others on the plasma spider a sheetcam forums

Re: jerky movement plasma table

PostPosted: Fri Apr 17, 2020 9:30 am
by kawarider
Still fighting with the post. In the post I uploaded here , there is m101 and m102. In the programs used for cutting yesterday, there is m10.1 and m11.1????!!!!! Strange. I will take a look there later. THC on/off is working anyway, that is not a problem. I am very carefull with a post that is is not flying around everywhere. From every computer I use, post has to be the same. No thinking, just cutting. So , this will need some investigation how that is possible.

The jerky movement has some to do with the small arcs, no doubt about that. I think the solutions mentioned above will fix it. Keep you posted about the result, thanks a lot.

Re: jerky movement plasma table

PostPosted: Fri Apr 17, 2020 12:48 pm
by kawarider
Thinking about thc on/off. It is in pathrules probably. Is that possible? Strange, those different m codes.

Re: jerky movement plasma table

PostPosted: Fri Apr 17, 2020 2:30 pm
by Robertspark
What sort of THC are you using?

There are a few macros that work in sync with the gcode (i.e. the machine does not slow down to implement then accelerate back up which can create [what some of us pedantic ] plasma users call a divot ....

These Gcodes are (from the UCCNC manual):
Enable THC (Torch Height Control) control for plasma: M205
Disable THC (Torch Height Control) control for plasma: M206

Enable the THC (Torch Height Control) delay for plasma: M207
Disable the THC (Torch Height Control) delay for plasma: M208


Enable the THC (Torch Height Control) anti dive function for plasma: M209
Disable the THC anti dive function for plasma: M210

Enable the THC (Torch Height Control) anti down function for plasma: M211
Disable the THC (Torch Height Control) anti down function for plasma: M212

Other synchronous G-Codes (actually "M"-codes (Miscellaneous / Macro)) are:

Activate synchronous fast PWM (laser) output: M10
Deactivate synchronous fast PWM (laser) output: M11

Activate synchronous fast digital output: M10.1 … M10.10
Deactivate synchronous fast digital output: M11.1 … M11.10


A pin can be assigned for each enable + disable function.