Second print not at Z=0 Geeetech Prusa i3 M201

[Sabbath]

Hi All.

The base of my first print didnt stick on one corner, so I cancelled it. I then reset the Z calibration carefully using 4 different points on the bed, However, now when i start the print job it only gets to within 2-3mm of the bed. If I then re-check the Z start position it returns to the correct position. Can anyone help?

[Roxy]

What version of the Marlin is loaded on the machine? There are full diagnostics that can be turned on if you are running RC-7's RCBugFix.
Also, in RCBugFix you get to edit all of those numbers from the LCD Panel.

[Sabbath]

The Geeetechs come with their own firmware, and i'm on the latest version of that. I think i might have been having trouble with binding on the Z axix. I have pulled the threaded rod out and made it a little straighter. I ran a die down it, but it was clean. Put a tap through the nut and it was a little tight so its been cleaned out now. Then ran the nut all the way down the rod and it was very smooth.

[Roxy]

If it comes from Geeetech, it is of questionable quality. I have a Delta printer from them. They clearly do not understand quality issues.

[Warmaster]

did this ever get solved? I have same problem and when i start to print, it raises Z axis by 0.3 (reading on lcd)
Any ideas or clues?

[Sabbath]

No, i didnt fix it, I just tweak the bed height so the print starts at the right place. However, it settled to be much closer than the 2-3mm i originally had, so there was probably some user error. Check your slicer settings -> print settings -> general -> z offset. IIRC the z offset moved the print head down, so if this is already 0 try making it 0.3.