that explains a lot... I expected something else :(
90mm/sec .2mm layer is pushing the limits on a UM1. The UM2 is weaker as far as I can tell. .1mm 50mm/sec is much more reasonable. I've been printing .1mm 30mm/sec at 220C for most things. I know - it's slow - but it comes out nice.
Today I dis- and reassembled the extruder and the head to be sure there is no problem. I could not find anything... So I start with some speed test...(this test was posted in this discussion: http://umforum.ultimaker.com/index.php?/topic/3976-almost-always-missing-layers-underextruding/ I used the 0.1 Layer without retraction Version)
But with different filaments. I also pushed filament by hand if the extruder start slipping just to be sure It is not the holder or Filament curling issue. (It wasn´t)
Interesting results:
Ultimaker PLA runs best, at all speeds (but needs a temperature from 210 up to 230 degrees)
Colorfabb (Olympic gold) starts well at 220 and might work until "full speed" 10mm3/s at 260 degrees
InnoFil (Silver) works well but only at 230 degrees and 80% of 3mm3/s (so very slow) (at this case: increasing temperature does not help, manual push also not)
FormFutura (White) starts working at 230 (3mm3/s) need to go up to 250 at 4mm3/s and stop working at 5 to 6 mm3/s
Finally an last years igo3D orange start at 230, 4mm3/s runs at 240, but 5mm3/s at 250 does not work again...
So as you can see very different results... I did not expect such differences...
Nexts days I´d like to run some retraction or straight StickFilament tests.
Maik
(How can I add Photos here?)
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gr5 2,224
90mm/sec .2mm layer is pushing the limits on a UM1. The UM2 is weaker as far as I can tell. .1mm 50mm/sec is much more reasonable. I've been printing .1mm 30mm/sec at 220C for most things. I know - it's slow - but it comes out nice.
There *does* seem to be some kind of problem with the UM2 extrusion rates, but it's very unclear what the problem is. Lots of people are working on it so I recommend you stay tuned. Unless you want to be the Hero who figures this all out. In the meanwhile, if you want pretty prints, it doesn't matter. Just print 30mm/sec, .1mm layer and 220C (or warmer).
Some of the thoughts of what the problem might be:
gunk in the nozzle - possible ABS from the black extruder housing
extruder issues including: weak stepper motor, filament rubbing much too hard against housing, bearing not spinning due to being too tight against outer wall, or inner pieces, white tension arm not applying pressure due to 4 extruder screws too tight, filament stuck on reel or coming in at too strong of an angle. Or it might be that different people have different issues.
6mm^3/sec is pretty damn good (although others get more). That's the equivalent of 150mm/sec at .1mm layers or 75mm/sec at .2mm layers.
No one has this figured out but even if it were fixed you probably still want to print 30mm/sec, .1mm layer and 220C if you want the most beautiful possible prints. Of course if you care more about functionality than beauty you are going to either figure it out yourself or wait a few more weeks until this is figured out. Or you can increase temp to 250C which is reasonable as long as you print at least 5mm^3/sec.
If you *do* want to experiment you might start with cleaning out your nozzle with a hypodermic (or taking it off), or printing at 250C for a few minutes to possibly get out any ABS, or you could try this experiment as it might lend something (who knows):
http://umforum.ultimaker.com/index.php?/topic/4222-pulling-force-of-um-extruder/?p=34887
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