Notice how the white parts, the filament stripped into pieces making the teeth slip, is not evenly distributed across the the teeth? That's probably because I have taken off one of the washers from the gear mount, and now the teeth are not aligned with the filament any more - which means less pulling power and more stripping. That can explain quite a bit - and it's amazing I got the fan duct as far as I did.
|See the bolt at the top? Not aligned at all. A wonder anything worked.|
So the right procedure for mounting the hobbed bolt and idler is:
Put in bolt with gear.
Check that the teeth align with the holes for the filament (they didn't) and add/remove washers as required.
Mount bearing and fixating nut on the other side.
Put in filament (loosely mounting the idler can help)
Tighten idler screws to where the windings are almost touching.
Also: A stovetop cleaner held loosely but moved quickly is great for popping off stuck prints.
Today's calibration is 0.5mm Z offset with 21C, 1022 hPa, 85% humidity.