Is there a way to jogg the Z axis past what the printer knows is the Z=0? I have a prusa i3 mk2s and I don’t want to rotate by hand the Z leadscrews to get the nozzle to the bed, which is what the manual suggests. I started the Calibrate Z and stopped the process after I jogged the XAxis to the top, making the motors skip to align it properly. Now I want to get it towards the bed and check everything with menus or g-codes not fiddle with my hands.
Thanks.
Yes, absolutely - as long as you are not actually bottomed out; using G-code; however, it is very very important to know that the printer is in Absolute and not Relative positioning mode.
G1 Z0; this tells the printer to go to the zeroed Z position
G92 Z1 ; this tells the printer that its current position is actually Z1
G1 Z0.5 ; this tells the printer to move down from what used to be 0, but is now 1, to 0.5, which is effectively -0.5 in the old coordinates.
I used to have to do this all the time with my old Kickstarter Printrbot - I failed to get the endstops put on properly, so I had to manually zero - I entered the G92 command manually, usually something like G92 X50 Y50 Z100; then I used the Pronterface movement GUI to slowly and carefully find my starting position, then I would do G92 X50 Y50 Z0 to set that as the center of my nominally 100x100 platform.
Interesting, thanks I’ll be trying that at some point. Still battling build-squareness-bed-level-issues. This MK2S kit makes me crazy.
Yes, my current printer is a Printrbot Simple Metal and uses a touch off sensor and four corners the bed, but that was not relevant to the question.