Well it seems I've entered the multimaterial hell once again; can't get reliable tool changes due to stringing that eventually clogs the feeder. After at least 7 tries I gave up, I decided not to spend my summer vacation debugging this crap.
So after fixing the extruders the problem manifested only later than usual. To combat the stringing, I lowered the tool change temperature to 190C. I usually print PLA @205C so now each time there's a tool change, the hot end will cool down to 190C before doing the tool change. This adds some extra time to each tool change, so the already long print is getting even longer, now up to 20h for simple 6-color benchy.
The temperature reduction did help quite a lot, the print progressed about to around 50% completion whereas before it usually failed around 20%.
Also the print quality is not very good in general. I'm using S3D for this print so that needs to be tuned too.
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This was found inside the feeder after investigating the latest fail. Also a crappy filament tip that most likely will cause a feed failure
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