CNC Tig welding

Hello all !
I have managed to put together a single axis TIG welding CNC machine for seam welding using Arduino & GRBL, using a GUI to send G code to the Arduino . The only hiccup is that the USB connection between the Arduino & the Laptop sometimes freezes when initiating the arc by HF initiation. When that happens , the g code that follows does not get executed, & the rest of the commands ( such as turning off the arc etc) have to be manually dealt with.
Can this problem be avoided by using Linux CNC & its supported hardware? If so , then how?
I have never used LinuxCnc before .
Hope this is the right place to post since, I did not see a CNC welding category anywhere.
Appreciate your help.

hello SSP,
the problem you have with high frequency will not solve linuxcnc, it is a problem of environmental noise, it is much easier, separates the control circuits further away from the TIG machine and isolates the masses of the two machines and put them to different lands , I also advise you that the control circuits are inside a metal box and connected to the ground, I hope I can help you.

This is something I'd like to see a vid of, sounds very interesting.

But the environmental noise advice is very sound indeed.

Linuxcnc can use ethernet cards which are better suited to noisy environments.
USB is not so good at noisy environments and or course are not realtime to begin with.
Hard to say without more idea what the actual problem is.
linuxcnc has been used with plasma cutters so can work well in that environment.

Chris M

Hi,

I have also done a project with Inox Tig welding on CNC. The problem is indeed the HF ignition start of the Tig welding inverter.
Also HF plasma inverters have the same problem and are not usable for CNC. Only the expensive plama machine's with HF start are
good insulated to work with CNC. Then we talk about branches Hypertherm or Thermal Dynamics.

To reduce the problem you can try :

1. Make a good ground connection => machine to earth cable and ground
2. Use a opto isolated break out board.
3. Use mosfet relais (torch start) in stead of mechanical click relais.
4. Isolate your cnc hardware into a metal box
5. Use a differtent power connection for your tig inverter.
6. If your computer screen is flickering you know it's not good.
7. My experence is that after a time (can be a few weeks) your computer i/o can be broken.

SSP :

Can this problem be avoided by using Linux CNC & its supported hardware? If so , then how?

No no no hihi

Have luck !!

To the text of Tommylight i added a picture for earth grounding of the machine

For all those who are interested..... a short video.
Fortunately, everything worked perfectly in this run. No crashes, hangups etc


The result

Hello SSP,
I think it's great that it works for you at last! I am also a welder and I have a tic machine to weld steel and stainless steel, but I did not have time to test it. I hope I can someday get it done, I have a question, how did you make the metal wire welding device?

thanks
Chimeno