Prusa i3 auto leveling

I just have a question about implementing auto leveling in my printer. Does the printer still reference Z=0 from the z axis endstop location? If that is the case, then when the printer runs through the leveling process, will it ignore that z axis endstop if say one corner was lower? Or does the printer not reference the z axis endstop at all and only reference from the extruder probe?

It's a two step process.

Part one, establish bed level using probe. If the Z end stop is wired in, it will be used in addition to the probe. I believe you have to wire the two in series as "normally closed". This means it will never go lower than the z axis end stop or the probed depth at any corner, which ever is hit first.

When running, the z end stop can still be hit and it would trigger a stop event on axis.

I'm looking at this for my i3 at the moment, so this is my understanding from reading the 94 page auto bed levelling thread

So do I need the z axis endstop at all? Could you possibly link me to that thread? Thanks.

Quote
Joe2014
So do I need the z axis endstop at all? Could you possibly link me to that thread? Thanks.

Here is the thread. The probe for the auto bed level essentially becomes your z endstop. However, some people for the sake of safety keep the z endstop as a failsafe just in case something happens and the probe doesn't work and isn't available to stop the z movement.

I have an I3 with auto bed leveling and with a hall sensor used as z-probe.

It retracts the probe when it moves to the bed because the magnet is attracted to another one on top of the probe.
Thus however will cause a short trigger of the hall sensor.
If marlin would stop when the z-end stop is triggered then this shouldn't work.

Quote
Draob
I have an I3 with auto bed leveling and with a hall sensor used as z-probe.

It retracts the probe when it moves to the bed because the magnet is attracted to another one on top of the probe.
Thus however will cause a short trigger of the hall sensor.
If marlin would stop when the z-end stop is triggered then this shouldn't work.

But it would work if the z end stop was set to be normally closed, so it would complete the circuit in series. I think that's the point, the z stops are usually set up to be normally open (Mine certainly are and I'm almost certainly normal)

Quote
brucehvn
Here is the thread. The probe for the auto bed level essentially becomes your z endstop. However, some people for the sake of safety keep the z endstop as a failsafe just in case something happens and the probe doesn't work and isn't available to stop the z movement.

That's the one. There's a lot of useful information in there, but I'm not sure I'd recommend reading the whole thing again