Oh, I did not realize the wrench example came as a g-code file (.nc) and not as a Carbide Create design file, so my suggestions above to adjust cut depth would not have been possible anyway. I wonder if the design file for the Nomad wrench tutorial is available somewhere (@WillAdams do you know?), it would be easier to finetune the depth of cut.
As far as I see in the wrench.nc file, the toolpath is set to cut down to 0.12" / 3.048mm deep.
Maybe you can measure the actual thickness of your material, this will give you an idea whether it’s “normal” that the cut did not go all the way through. If you get the same problem a second time, as @WillAdams said you can just reset your Z zero slightly lower and rerun the job.
As far as a good way to set Z zero, probes are nice but what they do is mainly make the zeroing process faster, not necessarily more accurate than manual zeroing using the “paper” method. I would suggest that you do a few projects using the manual/paper zeroing, then once you are familiar with the process you can decide if you feel like you need the probe.
The (very common) way I do the paper touch off is:
- jog down towards the surface using 1mm increments until you are about 1mm away
- reduce jog step to 0.1mm
- slide the paper back and forth continuously and jog 0.1mm at a time towards the surface, and as soon as you cannot slide the paper anymore, that’s where you set your Z-zero. Since the average paper is 0.1mm thick, this gets you very, very close to a perfect Z zero.
(disclaimer: I don’t have a Nomad but a Shapeoko)