Confusing nozzle blockage with PLA  

Confusing nozzle blockage with PLA

Hello everyone,

i'm kind of confused by my recent situation, i bought some PLA from dasFilament and already printed ~130h with the white PLA without any issues but when i changed to the blue PLA the extrusion would stop mid print with the extruder gears skipping. This would happen after about 45m to 1h, so when it happened i unloaded the filament, cut the tip off and loaded it back in, to my surprise the extrusion would be flawless again and the print was able to continue again for 45m to 1h after which the clogging occurred again. Then i unloaded the filament, aborted the print and loaded the white PLA and printed again with the same gcode. This time everything just worked for the entire print. Then i swapped back to the blue PLA and ran the same gcode, and the nozzle clogged again. I then disassembled my extruder and cleaned the hotend, there was no obvious contamination in the heatbreak or nozzle so i put everything back together and printed the same gcode with white PLA which again worked, then i changed back to blue and it clogged again. I tried changing the extruder pretension, increasing it delayed the clogging to some later point, but didn't solve it. I noticed that when the nozzle seems clogged and i unload the filament and try to load it back immediately it will not work, but when i cut off the tip it works. So the tip is somehow causing the clogg but it cannot make any sense of this since the tips of both white and blue PLA look very similar after unloading.

I really cant figure out what might cause this problem, except for the filament just being bad, but i cant really imagine this being the case.

I appreciate any help on this 🙂