Problem with material PLA, 3mm

[alaschgari 0]

Hello community,

we have difficulties to get a clean print result with PLA, 3mm material. The extruder prints very thin and no clean lines, but more or less dots...

What could be the problem?

Cheers,

Aljoscha

Edited June 5, 2015 by Guest

[gr5 2,229]

It's hard to say for sure but I'd say 90% likely it's underextrusion. It's hard to say because you get something slightly similar if after leveling the nozzle is too far away from the bed. That issue should only affect the bottom layer.

So assuming this is underextrusion, the most common cause is printing too cold or too fast. 220C at .2mm layers at 30mm/sec is nice and slow and safe speed to try initially. Your temp sensor could be off by 10C so you could even try 230C.

However I'm going to guess that in this case you have a different issue. I'm going to guess that the filament is partly stuck in the bowden tube. You may have ground down the filament and created a little flap of filament that then entered the tube and got stuck in there. Not sure. Or maybe your filament is too large (e.g. 3.01mm is too large, 2.85 is normal).

I would power cycle the machine to ensure the feeder motor is off, then heat the nozzle to 180C, then once it is at that temperature I would pull the filament out manually out through the stepper. This should be easy with only 1 or 2kg of force needed. Inspect the filament visually. If it takes more force - say 5kg, then something is wrong. If you can't get it out at all then likely it is stuck in the bowden. You may have to remove the bowden - there are small clips that need to be removed, then push down on the bowden holder while lifting on the bowden.