Ultimaker 3 Under Extrusion

[distance28 0]

Hey Guys,

 

I've been struggling with under extrusion with my ultimaker 3 for a couple weeks now. Whenever I start a print, it lays down the filament fine for the first 20 seconds or so, then the line width becomes thinner and eventually stops sticking to the build plate. I have done the active and manual leveling, cleaned out the nozzle, and verified the nozzle and bed temps. I would appreciate some help and advice for how to fix the solution. I've attached a picture showing the progression of the first couple passes.

Thanks!

[Smithy 1,141]

How does your filament look like on the feeder side? Is it grinded or normal?

You said you have cleaned the nozzle, with hot and cold pulls, as described on the UM website?

 

Your problem can have several root causes, like spool or tangled filament, feeder, Bowden tube, clogged nozzle, wrong settings (temperature, speed), so have to check everything.

 

What about the fan in the print head when you open the door? Is it running when the print core heats up? Check also if it is clean, there are often some strings of filament inside, which could block the fan. The fan (the middle one in the door) is important to keep the print head cool on the upper side (cold zone) which prevents that the filament melts near the Bowden tube.

[distance28 0]

Smithy,

 

My filament seems to look normal, no grinding present. I cleaned the nozzle using the atomic method that UM website outlines. I also disassembled the printcore and checked to make sure there were no obstructions either and everything looked clean.

 

I just pulled some small wispy strands from the fan but it didn't visibly or audibly make a difference on the fan speed. However, running the print again it does seem to be doing better, and the filament is sticking to the plate evenly now. The line width still seems to be thinner than expected. When printing the brim, the lines are suppose to touch right? mine are printing just thin enough where there is a small gap in between each line. 

[gr5 2,069]

With the bed far from the nozzle do move material and move the filament slowly and make sure it comes out okay.  You should be able to extrude some filament and it should be able to travel from the nozzle to the bottom of the printer in about 10 seconds (while slowly spinning the knob in move material).

 

Your photo isn't very helpful as I can't see where it stops extruding.  If it gets so thin and flat that the bottom layer is transparent then that usually means the head is too close to the glass.  Just push down on the glass while it's printing and see if it suddenly all squirts out.  If so you had bad leveling - nozzle too close to glass.

 

If the filament isn't sticking to the glass at all that usually means the head is too high off the glass.  That's my guess from the picture but it's hard to tell because you are only showing the good extrusion it seems.

[Ticking_Fox 0]

Re-check the fan in the flip down bracket - the few easy to remove wispy strands may not have been all of the debris that has accumulated in it - more can build up on the shaft (behind the fan blade centre hub, out of easy sight) causing the fan to under perform.

[MarioPetit 0]

On 3/4/2019 at 6:45 PM, Smithy said:

How does your filament look like on the feeder side? Is it grinded or normal?

You said you have cleaned the nozzle, with hot and cold pulls, as described on the UM website?

 

Your problem can have several root causes, like spool or tangled filament, feeder, Bowden tube, clogged nozzle, wrong settings (temperature, speed), so have to check everything.

 

What about the fan in the print head when you open the door? Is it running when the print core heats up? Check also if it is clean, there are often some strings of filament inside, which could block the fan. The fan (the middle one in the door) is important to keep the print head cool on the upper side (cold zone) which prevents that the filament melts near the Bowden tube.

I had exactly the same problem with my Ultimaker 3 and i have been trying to fix it for a week now.

Feeder tension, Bowden tube, hot and cold pulls ect.

Nothing worked so far, really frustrating.

But i did not check the fan.

Cleaned it now and there were indeed some filament strings inside that prevented it from running. 

Problem solved and my Ultimaker 3 works fine again.

Thx a lot Smithy for this great tip 🙂

Edited June 9, 2020 by MarioPetit