OXY FUEL CUTTING PIERCING DELAY

Hello..Everyone..I am new to Linuxcnc..I have set up a system that is running ok in X, Y, Z direction. It is running with a parallel port 5axis breakout board. If I connect spindle motor with VFD, that is also working fine with 0~10 V control for speed.
Now, I am planning for a similar arrangement for Oxy-Fuel cutting with SheetCAM to generate code. That is working in direction X, Y, Z but piercing is not working in CNC. The simulation in Sheetcam shows piercing delay, but no delay occur when running in Linuxcnc. The Gcode shows no delay command either. I can manually put any delay to the code, but that should not be the way for regular use.
How to incorporate piercing delay (delay time varies depending on plate thickness) to the system..Can anyone help?

You probably need to modify the onPendown() method in the Sheetcam post processor and add an appropriate G4 Pn where n = the pierce delay defined in the selected Sheetcam toolset. Before PLasmac was developed, we plasma users used to use a touch off routine that was called from that method which included the delay.
Something like what BigJohnT shared here.
gnipsel.com/shop/plasma/plasma.xhtml

It worked perfect..Thanks lot