I have been having problems with printing lately an i am really confused.
I have always had to have a negative g-code setup (about -0.4mm) in simplify3d to get the head close enough to the bed to get it to stick.
Now i thought i should check my z height and gamma value setting, but it is all really weird.
If i use the method to set gamma max as per the wiki: Finding gamma_max manually
First home the machine
Then set the current Z position to 0
Then move the head to the bed, using G0 Z(position) or Pronterface or the web interface.
Once the head is exactly at the bed, issue this command
As soon i enter G0 Z0 (as i think that should be at the bed) it want to go UP not down (crashing into my endstops at top).
If i use the other method (manual method)
The the machine thinks z0 is about 2/3 down from top (gamma_max is set to 618.2) as it is my height from top to bed.
But M114 says it is at z0.
Where does it get 2/3 down from??
And if i then jog down to the bed and issue the M306 Z0 command which will use the current Z position as a homing offset.
Then save to the SD card with M500.
It still wants to stop at 400 next time i use the G0 Z0 command. It does not save the setting it seems.
If i G28 (at the top at endstops) and M114 it reports z 400.6791