Ultimaker 2 Extended - Feeder keeps skipping

edkoch · March 25, 2016

Feeder keeps skipping

Model: Ultimater 2 Extended

Hey guys,

I'm a little bit confused. After hours of printing suddenly the feeder of my Ultimaker 2 Extended started skipping: Video: https://drive.google.com/file/d/0B7KyR2ULRkeQa3U3VW1INGg1bms/view?usp=sharing

What I already tried:

--> doesn't skip, when the hose is not inserted
changed nozzles
changed the hardness of the feeder

Have you got any ideas to help me? Because actually this skipping causes the feeder to not transport the filament fluently, so that the prints come out bad.

Thank you

Werner Koch

Edited March 25, 2016 by Guest

gr5 · March 25, 2016

This is very common. The stepper motor can only push so hard - about 5kg of force. There can be many causes but seeing the incredible speed of that motor I'm guessing you are just printing too fast. The hotter the filament is, the less viscous it is. So at 190C the filament is more like toothpaste and at 240C PLA is more like honey.

Did you change to a smaller nozzle size recently? Did you change filaments recently (some PLA needs higher temperature)? Is it possible you are now printing ABS and before PLA?

Check all the printing speeds in cura - especially the infill speed (which should be zero):

Here are my recommended top speeds for .2mm layers (twice as fast for .1mm layers) and .4mm nozzle:

20mm/sec at 200C

30mm/sec at 210C

40mm/sec at 225C

50mm/sec at 240C

The printer can do double these speeds but with huge difficulty and usually with a loss in part quality due to underextrusion. Different colors print best at quite different temperatures and due to imperfect temp sensors, some printers print 10C cool so use these values as an initial starting guideline and if you are still underextruding try raising the temp. But don't go over 240C with PLA.

What is your: print speed, nozzle size, layer height, printing temperature? Material? I want to see if you are within expected printing speed range.

Edited March 25, 2016 by Guest