RE:
One more thing. If you manually move the print head to the back left corner, is the main cable and PTFE above the X-axis motor and not getting caught between the motor and the print head?
RE: Print not centered on the bed
One more thing. If you manually move the print head to the back left corner, is the main cable and PTFE above the X-axis motor and not getting caught between the motor and the print head?
Thanks for that check. No - no problem in the right rear corner. HOWEVER, the cable wrap that secures the Teflon tube to the extruder cable (the one that is closest to the extruder) interferes with the nuts securing the vent cover. This happens when the extruder is very close to the front of the machine. I'll have to check the instructions to see if I have it wrapped wrong. This could very well be the smoking gun.
I'm still not sure why the periphery test print worked perfectly.
RE: Print not centered on the bed
Right -- if the print head runs into an obstacle a few mm away from the left or front edge of the printable area, that would shift the print towards the back/right . But only shift it once, since it is now in the ara the print head can reach. That would be consistent with what you observe.
RE:
Thanks for that check. No - no problem in the right rear corner. HOWEVER, the cable wrap that secures the Teflon tube to the extruder cable (the one that is closest to the extruder) interferes with the nuts securing the vent cover. This happens when the extruder is very close to the front of the machine. I'll have to check the instructions to see if I have it wrapped wrong. This could very well be the smoking gun.
I'm still not sure why the periphery test print worked perfectly.
Yeah, I'm becoming certain that there is some sort of physical interference in which the printer to loses steps in the X direction. This would explain the shift. This commonly occurs when the cable and PTFE sag and get caught between the X-motor in the back left corner and the print head. Usually though the shift happens in X and Y.
Also, one of the best mod's I've installed is this one: Prusa Core One Magnetic Top Cover with Integrated Vent Handle not only does it make it much easier to remove the top but it also gives additional clearance.
RE: Print not centered on the bed
That was it! A simple mechanical interference. I had the first wrap that secures the Teflon tube to the extruder cable too far forward. Looking at the instructions I needed to move it back about 2 inches. This is enough so it clears the nuts under the vent cover.
There is still a small interference with the Teflon tube and those same nuts. The tube can open and close the vents. This is not a show stopper, but probably not what Prusa intended.
Thank you both @hyiger and
RE: Print not centered on the bed
@jurgen-7.