I noticed a knocking noise one day on my QIDI and things seemed fine at first glance, then 7 hours later my print only had 3 layers. So I figured it was a jam, and I cleaned it out but every now and then I heard the knock again which cause incomplete prints. When I went back to remove the front facing cooling fan I noticed one of the screws that go through the fan to the stepper motor wasn't secure. This was causing the filament guide to rock out of place periodically until it got worse and worse.
I've been trying for hours but the screw just won't "catch" on the stepper motor that feeds the filament into the extruder. The screws aren't stripped because I can take the motor off and screw them directly into it with no problem. It's as if they aren't long enough anymore or that they're bent.
Has anyone else had this problem & found a solution that works consistently?