Material stops flowing 20 mins in

[muffinkiller86 0]

Hi everyone

Having a major issue with a new UM2 (I am new to 3d printing). I've mad a few "successful" (but poor quality prints) and results seem to have been getting worse.

I'm using grey PLA which came with it, with settings:

 

1. 220 Temp
   
2. 45 Bed with glue
   
3. ~30-50 speed
   
4. 1.2 shell thickness
   
5. 0.12 layer height
   
6. 12% densisty
   

 

The model I'm printing is: http://cl.ly/413q0J24332M I have no issues with it sticking to the bed with the above settings.

Around 20 mins in, I notice the flow just stops and the printer continues merrily along without printing anything so I have to abort.

I've already tried changing nozzles, cleaning the 2nd nozzle with the atomic technique (its clear - I can see through it), tweaking the extruder bolt.

Is the machine faulty?

[izzy 33]

I can't see the model other than the file, does it have a lot of retractions?

For PLA I would try 205'C to 210'C, I would also check that all the various screws are nipped up tight. Also check the pressure on your feeder, if the pressure is too high, during a lot of extractions, the filament can get squashed which then will get stuck as it reaches the coupler before entering the nozzle. To check, heat the nozzle to about 200 and then manually pull back the filament, have a look at the shape of the filament near the end. If it is squashed adjust the feeder to reduce the pressure, I would then recommend printing off Roberts improved feeder it's the bees knees, much easier to set up a nice pressure and swap filaments. I've also done a few little bits to help add to Roberts feeder.

[IRobertI 520]

Have you checked the third fan? The tiny fan that is at the back of the print head. Depending on how new your printer is, this fan will either turn on immediately when the printer is turned on, or as soon as the temperature goes over 40C.

[madness 2]

Hey there MuffinK-

I too have a new UM2 and have had a few extrusion issues, same symptoms as yours, and I found that as I print, the tension on the filament as it is pulled from the reel gets pretty tight at the feeder, causing no filament or very little to get into the head.  The reel tightens gradually as you print until...no extrusion.  I have printed Roberts feeder, but haven't installed it yet so I simply have my filament reel sitting flat on the floor and make sure I have a bit of slack in the filament.  That solved my prob, perhaps it helps you.  You will end up having this problem when you get to the end of your reel, anyway...those coils are so tight that my PLA snapped in 4 places (all before the feeder, whooo).  That is actually when I figured out that tension prob.  There were also several posts about this issue earlier but they may not have been restored to the new forums.

I would take a bet that your 2015 UM2 is running just fine, but if it actually is not up to par, then you have the guys that design and build the machines right here on the forums, in addition to various customer services, and I have seen that they take care of problems...don't even sweat it!

Regards-

MadNess

Edited May 17, 2015 by Guest

[muffinkiller86 0]

Thanks for the tips. I managed to successfully print Roberts feeder by placing the reel on the floor as suggested by madness. Did this with 100% infill which worked really well.

Just need to find a longer screw then I should be good to go with the new feeder Fingers crossed!

[JohnFox 25]

Make sure the spool is running freely. Mine proved very hard to rotate at first. A TINY smear of Z axis grease on the top of the spool holder made a dramatic improvement.