What’s the standard for WCS and offsets?

I’m completely new to CNC turning and I just got done with my Chinese 7x14 lathe conversion.
I was reading about the procedure for tool touch off on the LinuxCNC lathe page and I realized I have no idea how to setup my tools or WCS. I also watched a couple of videos about setting tool offsets on HAAS lathes and got even more confused

Using the touch off methods described on the lathe page, is the standard to set the X on all WCS to zero(e.gG54 X zero = machine X zero) and rely on the tool offsets with G43 so that the offset X position in the current WCS is always spindle center while the Z tool offset is set relative to some reference tool? I guess this way I would only need to set the Z zero for the current WCS by touching off on the part’s face using the reference tool? Obviously this wouldn’t apply to boring bars and tools oriented parallel to the spindle.

what confused me watching the HAAS videos is that their tool table appears to store offsets in machine coordinate systems after doing a “measure radius/diameter” which seems to subtract the current machine coordinates from the test part radius/diameter. Linuxcnc seems to store arbitrary or absolute offsets with no reference to any WCS….at least that’s how I have it setup on my router. 

 

Makes sense! After watching the tormach videos I think I prefer the HAAS method which I guess is not based on a master tool but rather absolute offsets for each tool in X. After playing around a little, I think I do prefer your suggestion of using the Z offsets relative to a master tool(a facing tool) this way the WCS offset in Z needs to be setup one relative to the master tool, but the X is always absolute and never need to be changed since the spindle center doesn’t change. So currently all my WCS offsets are zero in X and vary in Z based on the part, tools offsets in X are all relative to machine zero while Z is relative to my facing tool. This also works well for my cross slide drill chuck which always needs to be centered and only needs Z offsets depending on the workpiece and how the bits end up getting mounted.

this guy covers it in good detail