Yup, I get it. (Trust Me!) Your question is spot on... So, here goes... But only cause you asked! ;-)
As I dig deeper and deeper into understanding how to get my machine (and my process) working, I seem to encounter more fundamental issues...
When trying to "Ref Home" all the axis, the X and Y worked OK (hit the stops and then zero'ed) but the Z-Axis did not. I've had it hit the upper stop (and then emergency stop) or had it drive into the table (and manually emergency stop) depending on whether the machine coords for its current position were negative or positive when the "RefHome" operation began.
So, "digging deeper", I thought maybe I should just try and manually zero the machine coords. Its not a final solution to my issue (RefHome), but I figured it should be pretty straight forward, right? Nope...
I'm trying to get to the simplest possible operation which I can successfully perform (to ensure my config is good) and then work my way back out to a more automatic operation (RefHome).
1. I should be able to manually zero the machine coords, right?
2. Otherwise, should I start trying to figure out why my RefHome on the z-axis is not working? Its home movement seems to be determined whether the current machine coords are negative or positive. Obviously, I want it to go up, hit the stop, back out a little and then zero the coord... But even when it does move in the right direction, it recognizes the stop, but "emergency stops" the operation. (My homing/endstop config appears to be correct...)
What do you think? Thanks!