So my K1 max has been printing abs great for years but suddenly started stopping feeding after a few layers. The extruder motor was very hot so I thought heat creep and slowed the printing speed, dropped the chamber temp. Still kept happening but after each failure I was able to extrude filament showing that the nozzle was not blocked. Then I realized that even though it was not feeding the extruder motor was rotating but no extruder clicking. I finally changed the nozzle and now OK but I don’t understand what was wrong with the original nozzle.
bilmar, the nozzles are wearable items, glad to here that you got years printing ABS on a single nozzles. but here is a list of what could have caused the issue
- Backpressure under flow: Manual extrusions push filament slowly, allowing molten ABS to slip past partial blockages or carbon buildup inside the melt zone. During high-speed printing, backpressure spikes significantly.
- Filament slipping vs. clicking: When backpressure exceeds the grip of the dual gears, the gears shave the ABS flat and slip smoothly over it without slipping back and clicking.
- Internal bore wear or carbonization: Micro-burrs or cooked filament lining the internal throat act like friction brakes once the filament softens near the melt zone.
Thanks, I think your option 1 was the cause the cause. A partially restricted nozzle allowing the filament to be extruded but eventually causing the extruder to overheat and then shave the filament and continue running. Thanks for your input.
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