Hi, I'm facing a strange problem with my MK2.5S. During a print I'noticed that the extruder motor was skipping some step, so I tried the cold pull method. It seemed to be ok for the first print and then the problem happened again. After that, I tried the cold pull method for several time with different PLA filaments. The filament comes out from the extruder and the unloaded part is clean but, if I start a print, after some layers the motor begin to skip steps. I tried to change the ptfe tube but it didn't help. I Think that the cause may have been a poor quality filament. Anyone is facing the same problem or already solved it ?
Have you tried adjusting idler tension?
Is the filament getting warm?
If the filament is getting warm then it might be that. I think the PLA softens and causes skips. In my case, my printer is in an enclosure and in the summer I have to leave the doors open when printing PLA. If I don't, I get similar symptoms - prints starts out OK and after a while the extruder starts skipping. Actually, I've solved it by doing several things, though I don't know which of these is the critical one:
I generally run in 'silent' mode but I have added 'M907 E500' to startup gcode to turn up the extruder current a little (only as much as normal mode). This probably makes it run hotter, but less likely to skip.
I leave the enclosure doors open if the room is warm - I try and keep the air immediately around the top of the printer under 30C (I have a digital thermometer with a sensor at that level so I can check).
I have added heatsinks and an extra fan to cool the extruder stepper so it doesn't get hot so it doesn't conduct heat to the hobbed gear.
And contrary to ian-s3, you could also try increasing your extruded temp by 5°C and see if your filament is not heating up fully.
I have an enclosure too. Until now the printer has printed fine with or without the doors open but I will try your advice, Thank you.
I will try this too 😉. Thank you