How to determine your Z home switch offset

Here is a method for determining the switch offset on your Z home switch.  If your torch is mounted on a floating head with a switch, then it will have to move some distance after the torch touches the metal before the switch will trip. One simple method to find this distance is as follows:
  1. First make sure the Home Switch Offset is set to zero in the Configurator.
  2. Start CommandCNC, make sure motor power is on and click the “E-STOP ACTIVE” button to bring it out of E-Stop.
  3. Make sure the torch is over a solid piece of metal which will not move down when the torch presses down on it.
  4. Click the “Home Z” button.  The Z should move down until the switch trips, and then move back up slightly until the switch opens again.
  5. Make sure the DRO reads 0.0000 – if it does not then click the button labeled “Zero Z”
  6. Then set the “Jog Speed” slider down very slow – probably 1%
  7. Using the Page Up and Page Down keys, move the Z up until it just barely clears the metal.  One way to tell is by moving up so you can slide a piece of paper under the torch, and then carefully move down until you cannot pull the paper out.  If you have a FeatherTouch Ohmic sensor, you can see the contact light go out when it no longer is touching the metal.
  8. Once you are sure the torch is just clear of the metal, write down the value that is in the Z DRO.  This will be a positive value, but needs to be entered as a negative value in the Configurator.
  9. Now close CommandCNC, open the Configurator, go to the Axes page, Z Axis page, and enter as a negative number.  This means you put a minus sign in front of it.  So if the value was 0.080, you will enter -0.080
  10. Save and exit the Configurator, and you should be done!