Cnc plasma cutter delay on motion when firering

[the_ducklet]

hello everyone

i´m building an cnc plasma cutter, using arduino uno with GRBL.

i have all the controls dialed in and all is working, and the relay for the torch works.

but my problem is i would like too put in a delay from when the torch fires, to the X/Y axis starts moving, so the arc can pierce the steel before it starts moving again.

i´m using USG as software to run the G-code, i have also been trying with lightburn, but i dont seem to be able too find anywhere, i can delay that time

kind regards Anders

[gilshultz]

There are several ways to create a delay. The worst is the delay(time) function or much better is to use the mills function where you save the existing count, then keep checking it until mills count is higher than the sum of the time you want and the saved count. It is based on a 32 bit counter that is increased each millisecond.

[johnwasser]

What GCode commands turn the plasma cutter on and off? Is it treated as a spindle? Is it the "S" (spindle speed) parameter on the G0 and G1 commands? Is it done for you for the duration of G1 commands?

What is generating the GCode commands?

[wildbill]

You could hack USG to delay when the torch comes on.

Far cleaner would be to persuade whatever generates your G-code to issue a dwell (G04) after the torch lights.

If you have to, you could postprocess your G-code with a custom program to add the dwell.