So tiny, I could hardly photograph it properly using my phone. And yet this minuscule hex screw was the reason my Ender 5 Plus took a lengthy vacation.
From one day to the next, it suddenly would no longer extrude properly. Since it had worked fine until then, and the symptoms looked like a stuttering extruder, I knew from stuff I’d seen that one of a few causes might be the culprit.
Since it was my birthday almost, I asked the guests for gift cards, and bought myself a Micro-Swiss direct drive extruder kit.
It came in a tiny box, with full assembly instructions provided by a QR code that sent me to the Micro-Swiss site. Nothing wrong there, the upgrade went off without a hitch, but went test time came, my problem was not gone.
And then my next assumption was an incorrect one: I immediately thought the problem was still the same, and went looking for the stepper driver in order to check its driver current. Some E-mail discussion with the seller of the printer, since now thought it was a warranty issue. He did not reply immediately, but last night he came with a question: does the extruder also stutter if it does not have filament?
And that is when I noticed what I’d missed thus far: the stepper motor would hiccup always on the very same position! After that, the cause was easily determined:
The tiny screw that held the left cog of the extruder fixed to the stepper motor was a protruding a fraction of a millimeter too far from the cog and hit the aluminum arm of the right cog when turning. Since that event was concealed behind the two cogs, I never noticed it before.
Taking a file to the arm and removing a millimeter or so off the arm I was able to get it to turn freely again, and that solved the problem nicely.
Of course this does not explain why the printer failed in the first case, but that’s water under the bridge: the new extruder and print head work so nicely, that I was able to change the printing speed to 200 mm/s instead of the previous 120 mm/s. I am very happy with it’s performance now, and removing Octolapse from my setup made another problem disappear as well. So I guess we’re back!