Floating head touch off

Hello everybody, I am building a floating head with a switch. it is connected to "probe in" pin. Searching in the forum I found some touch off subroutine codes for example the following that was posted by BigJohnT

o<touchoff> sub
(#1 pierce height, #2 pierce delay, #3 cut height)
F10
G38.2 Z-1.75 (Probe to find the surface)
G92 Z-0.070 (Set Z Probe Switch Offset)
G1 Z#1
M3 S1
M66 P0 L1 Q5 (Wait for Arc OK from Torch)
G4 P#2 (Pause for pierce delay)
F25
Z#3 (goto cut height)
o<touchoff> endsub
M2

it looks good and I understand how it work what I don't understand is how to integrate this one with the gcode generated by Sheetcam
Should I copy and paste it in the Gcode generated by Sheetcam?
is there any way to integrate this code in Sheetcam? I mean that it was include automatically in Gcode generated before a new path cut

thank

You can edit the sheetcam post processor to call the touch off sub in place of a M3.

Rick G

Here is my sheetcam post.

gnipsel.com/shop/plasma/files/EMC-Plasma.scpost

Just in case that is not the latest post I attached the current ones from my plasma.

JT

Thanks Rick G and BigJohnT. I am understanding now. Just to clarify. So if I edit the post procesor of sheetcam and include the subroutine then I have no need to include the subroutine in the G-code manually as the sheetcam will include it automatically. that is correct, right?
sorry for the question but I am newbie. Every day I learn a bit more.

Thank you friends

If you use my post processor then place the touchoff subroutine in with the rest of your subroutines and the post will add the call to it with the proper parameters.

JT

Just to clarify. So if I edit the post procesor of sheetcam and include the subroutine then I have no need to include the subroutine in the G-code manually as the sheetcam will include it automatically. that is correct, right?

Yes.

And as John said you need to have the subroutine located in the proper location.

Rick G

Hi guys, the zip file John attached opens as a zero byte file for me. Can someone share the Sheetcam post he posted. It seems to be the most recent resource.

Uploaded again, note that the touchoff.ngc shows 0 bytes when you hover over it with the mouse but it does have the contents.

JT

BigJohnT wrote: Uploaded again, note that the touchoff.ngc shows 0 bytes when you hover over it with the mouse but it does have the contents.

JT

Thanks John, It works for me now. Very much appreciated.

Hello i have downloaded the post and installed it to sheetcam, but my g-code have no call for subroutine, only M03 even if i can see in the post that it should be there, my file extension is also .tap is that correct? (i know it is easy to change in linuxcnc)

here is some code:

N0010 (Filename: hengsel.tap)
N0020 (Post processor: LinuxCNC plasma.scpost)
N0030 (Date: 15.06.2017)
N0040 G21 (Units: Metric)
N0050 G40 G90
N0060 F1 S1
N0070 (Part: hengsel)
N0080 (Operation: Outside Offset, VISIBLE, T1: Plasma, 2 mm kerf)
N0090 G00 Z10.0000
N0100 X10.9991 Y6.6278
N0110 Z6.0000
N0120 M03
N0130 G04 P0.3
N0140 G01 Z2.0000 F100
N0150 G02 X10.9991 Y6.6278 I-0.0000 J4.2500 F3000.0
N0160 M05
N0170 G00 Z10.0000
N0180 X27.5577 Y52.0694
N0190 Z6.0000
N0200 M03
N0210 G04 P0.3
N0220 G01 Z2.0000 F100
N0230 X11.1225 Y40.4732 F3000
N0240 G03 X9.6860 Y39.2634 I6.3417 J-8.9879 F3000.0
N0250 G01 X5.5778 Y35.1552 F3000
N0260 G03 X2.4665 Y28.9326 I7.7782 J-7.7782 F3000.0
N0270 G01 X0.1096 Y12.4334 F3000
N0280 G03 X18.7772 Y18.6560 I10.8895 J-1.5556 F3000.0
N0290 G01 X15.9488 Y21.4844 F3000
N0300 X44.9716 Y50.5072
N0310 G02 X44.9716 Y47.5656 I1.4708 J-1.4708 F3000.0
N0320 G01 X41.6776 Y50.8597 F3000
N0330 G03 X27.5577 Y52.0694 I-7.7782 J-7.7782 F3000.0
N0340 M05
N0350 G00 Z10.0000
N0360 M05 M30