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You can add me on discord, my username is onceloved.cn I can use TeamViewer to remotely configure for you

My graph in the plasma primer in the linuxcnc docs is the only real data I have seen about volts over distance.
linuxcnc.org/docs/stable/html/plasma/plasma-cnc-primer.html
It showed for the specific machine, it was 7.53 volts per mm with 99.4% confidence over 16000 readings. So a 2 volt range is a good target to get your 0.01" which is realistic
You voltage will be around 130-150 volts when cutting. I have run a 300 v full scale and also 170 to 200v an I never saw any difference. I would just use your thcad 300, seeing you have it, set it to 1/32 frequency and make some parts.

I tried to draw a picture to ilustrate the issue with the 2D clothoids stacked on each other to approximate a 3D clothoid.We want to connect a straight line in y with another line in x. The second one isI tried to draw a picture to ilustrate the issue with the 2D clothoids stacked on each other to approximate a 3D clothoid.We want to connect a straight line in y with another line in x. The second one is also shifted up in z. The 1) picture shows a 3D drawing of the situation. Pictures 2) and 3) show the xy and xz planes respectively with how the 2D clothoids would look like respectively.

 

The 2 clothoids look fine by themself, the one in xy is also close to the correct one I guess. The issue is with the second one in xz. The clothoid optimizes curvature in this xz projection so you get linear increasing and decreasing curvature relative to arc length in this projection but not linear in total 3D  arc length. In this example the difference is quite extreme because the curve is initially moving mainly in y and not in x. So the resulting curve does not behave as expected. Picture 4) shows the resulting curve in the yz plane, the tool is barely moving in z for quite some time (because the machine is mostly using in y and this direction got ignored for the clothoid calculation. Then it suddenly needs to move quite a lot in z and jerk is much higher than expected from the xz clothoid.
I hope I managed to explain this, it’s kind of hard to visualize 3D clothoids.

So in summary this approach leads to a smooth curve with fitting curvatures at the ends but in between the change in curvature and torsion is not linear and jerk might be higher than expected. The resulting connection curve also dependens on the orientation in the coordinate system. If the example was rotated for example by 45° the resulting clothoids would look differntly. This is of course kind of unintuitive.
So it does work to some extend but is not the best solution and there might be more extreme edge cases where this might  go wrong.

tommylight wrote:

Anyone against deleting this topic?

 

Delete away

not Hererunterfahren , sondern Herunterfahren. "drive down"?

AI tells me on a short "Ethernet controller setup LinuxCNC" search, what the "hottest 10 Windows11 Laptops of 2025 are".
Maybe how to fix the Wifi on my phone?

Just for fun translate: "vibration tumbler" to Chinese with an AI translator. Then feed the result back into picture search. (just for safety do not do it when someone is watching)

German for bicycle = "Biobike" (what???) it was Fahrrad, when i left.
Dictionaries made from dead trees were still a thing. it is a mess!

The closed form solution from the Frego paper only works if the clothoid starts with curavture and torsion = 0 aka from a straight line. So for our usecase this can not be used in all situation, only if we we want to connect to a straight line and not to arcs or splines etc.

Thanks for the new paper, I will read it later.

Hobby 3-axis mill, Raspberry Pi 4B, official download - reports as Gmoccapy 3.4.6.
Done several jobs since swapping from AXIS.

Running code - then stop.
No pop-up messages.
Found the Gmoccapy Log - nothing.

Cancelled job, but machine would not jog.
De-activate controls (Green/Red PB), then activate - machine jogs.

Need some hints on where to look, or a list of typical problems.
Thanks,
John.

 

Aciera wrote:

Oh, I just realized, 'pyvcp' panels are for the AXIS GUI.
Gmoccapy uses 'GladeVCP'
linuxcnc.org/docs/html/gui/gmoccapy.html#cha:gmoccapy
 

Ok, not sure how I do that as I used the stepconf wizard to create the config files and it created the pyvcp files.
Do I need to install a different version of linuxcnc if so which one as I just selected the latest 2.9.4 version?

Thanks again for taking the time to help, I really do appreciate it.