Print layers of first prints shifting on Z axis
So I'm new to 3d printing and I've just finished assembling my Prusa Mini + (hooray!), and seem to be struggling with some layer shifting. Beforehand, when I tried the first print using the prusa logo, the top layers got messed up a little/ended up missing. Thought the nozzle was clogged but realized I had to re-tighten the extruder motor. Other than that, print A seemed pretty fine. In the process I also had to adjust the z axis pulley and tighten it because it was too loose (realized this after updating to latest firmware and performing a selftest).
Cue print B, filament came out just fine! However upon closer inspection some of the layers and shifted along the z axis. I tried and checked everything I could based on what the guides tell me about troubleshooting with shifted layers. Made sure the Z axis motor wasn't loose, kept the tension on the pulley tight, made sure nothing was obstructed, kept the rods lubricated... so I tried a 3rd print. Print C was still shifting the layers so I stopped the print.
I have some images here. From left to right are prints A, B, and then C.
How do I keep the layers from shifting like this?
RE: Print layers of first prints shifting on Z axis
As it's a well known model, we can exclude that as a cause. My money is on loose grub screws, the ones that keep the pulley to the motor shaft. Two on each x and y motor shaft, one of which has to be tightened against the flat side of the shaft.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Print layers of first prints shifting on Z axis
Huh....! So I checked the grub screws, they were already plenty tight but I re-adjusted them anyways just in case. Then I realized the screws attaching the X axis motor seemed a tad loose, thought maybe having anything too loose there might cause things to wiggle or... something. Re-calibrated nozzle height as well and when I got it printing again, things turned out perfectly fine!! No more shifting or wobble. Problem solved! I think the issue must have been one of the latter two there. Now that is a clean print.
