My worked perfectly out the box A1 started working increasingly imperfectly after the first few days. Part of the problem was the “Four screws loose” issue, but that wasn’t all.
I was getting increasingly horrible seams, blobs, stringing… All things relaetd to filament flow.
And then the Z offset somehow dropped itself so low the nozzle was almost gouging into the build plate.
I didn’t bother with support as I needed the machine up and running asap.
So, I ordered a new extruder. Not because the extrusion was bad, but because I was 90% sure it was the eddy current sensor failing.
Four days later, the extruder arrived. Not the easiest thing to fit, and these printers definitely seem designed to “just work” rather than just be worked on, but managed to get it apart and back together.
And now I have the glassy first layer I was getting when I first got the printer. I also seem to be getting the overall print quality I was getting too.
Interestingly, there was a sort of white film/ powdery coating around the nozzle and on the build plate under the extruder, as though something released its magic pixie printer dust, but I don’t know if that’s actually related.