For many years, I've located the Z axis of my work coordinate origin by always keeping a sharp-pointed engraving bit in tool position #1 (It was used frequently, as well.) and touching this to the top of my workpiece as Z zero, along with having indicated-in the X and Y at that location, then all three axes were zeroed. H1 was always at a value of zero, then all the other tools had a length offset by the amount they were either shorter or longer than the engraver in #1 position. Pros or cons to this method?
After about 30 years away from one, I'm now getting used to working with a Fadal again, and things aren't quite so simple as what I've been using previously. It's gotten me to wondering, how is the Z zero set in your G54, etc? Or, do I only zero the X and Y, and then let each tool length offset (H__) just be whatever it is relative to the machine's home location (for Z) ?