Wiring floating Head switch

[northcj]

After years I'm adding a floating head to my table. Getting old and maybe having seniors moment...
Have Mach3 using a parallel port BOB. Is the wiring as simple as wiring from one of the input pins (eg 15) to the switch to ground? I recall parallel pins are +5v? And defining either one of the Z Home or Probe pin inputs as port 1 pin 15?

[acourtjester]

It needs to be setup in Mach 3 as a Z home and the Post Processor is using G28 for the Z axis and the home for Z is positive. In the home and limit
settings. This PP should work fine

Mach3 plasma mod Floating HeadTHC with probe Home at end.zip

Z home1.JPG

Z home 2.JPG

[northcj]

Thanks.. What about the actual physical wiring?

[acourtjester]

The wiring is to the controller one wire from the comm on the controller to the switch. The other from the switch to pin 15 input. When you home Z it should go up. Try this Have the Z about 1" above the metal, after the g-code mach3 should show 0.09 in the Z dro You need to have the metal wired to comm this is also what the plasma work cable is wired to. I use a foam block with a piece of tin foil on top with a wire to the plasma work connection and tin foil ( soft landing if not going right). This routine is with the switch offset about 0.027" video below with info to find your switch offset. the video of the torch action was my first attempt and the long upward action in not normal, it should just go down touch the metal back up the offset amount then go to pierce height and fire the torch
N0230 G28.1 Z0.02 (Start Touch-Off )
N0240 G92 Z0.0
N0250 G00 Z0.027 (Switch Offset Lift)
N0260 G92 Z0.0
N0270 G00 Z0.0900 when actually using the touch off it should be 0.150" for pierce height in the G-code

Z home1.JPG

This video shows how it works you can see the offset of the switch with the torches touch off.
https://drive.google.com/file/d/1trqpDy ... sp=sharing
Here is a video showing how to find the offset amount for the floating head switch

floating head switch offset.zip

[northcj]

Thank you and Merry Christmas

[acourtjester]

Not sure how you have your home and limit switches wired but I had the all in series as shown. This includes the floating head switch as the G28 command is a homing one. So this uses only on input to the controller and makes room if you are using a THC which needs 3 input pins.

switches.JPG