Plagued by Under-extrusion

[9thoracle 3]

Hello everyone,

 

I have been plagued for quite some time by an under-extrusion issue and I am at my wit's end.
Below is the Problem, My general settings, Some context, and what I have tried as a result.

Problem:

As shown in the attached picture, 2 of my 3 Ultimaker 2+ machines have an under-extrusion issue.
They both have the exact same amount of underextrusion. And it remains consistent through the entire part it prints, regardless of print size.

The first layer will print perfect. Every layer after is under-extruded. 

Settings:
Carbon Fiber HTPLA from Protopasta.
Hardened Steel Nozzles

225C Print temp
0.24 mm Layers
0.55 Lines

0.6 mm Nozzle
45 mm/s Print speed (all speeds expect for travel which is 100)

Flow Rate 100%

First Layer is 0.4 mm thick
First Layer speed is 25 mm/s

More Context
The two printers that are not working are at work

The other printer that works 100% fine is at home

The room temperature at work is about 70F

The room temperature at home is about 60F (Basement)

All 3 printers were originally Ultimaker 2 machines that I installed the + kit on.

All settings and hardware on the 3 printers is IDENTICAL (Ive gone through it several times to make sure)
I print using 3kg rolls

What I have tried

Gr5 has a list of things to look at that he posts when responding to people on this topic and I have gone through all of them.

I have actually replaced bowden tubes, couplers, nozzles, thermometers, heater cartridges, and the feeder gear assembly to try and fix it, but the problem has stayed the exact same.

This leads me to think its an issue with firmware or Cura version. I have confirmed that all 3 printers have the same firmware, cura version, etc. And it still is the same.

I have changed the temperature anywhere from 215 all the way up to 240 but that hardly affects it.

 

At this point the only thing that I have not done is completely change out the control board. But I am not sure I can even get any of those anymore.

Again, the first layer goes down PERFECT, but then it just under-extrudes after that. But remember my printer at home has the exact same settings and slicer config and does just fine, so I am flabbergasted as to what the issue is here.

Any ideas?

 

 

[geert_2 557]

If you haven't done these already:

 

Maybe take a gcode file that goes well at home, and try that on the printers at work? And take a file that goes wrong at work, and try that at home? Then you know whether it is in the gcode or not?

 

Exchange spools of filament at home and at work, just for a testprint. Print both with the same gcode file. Then you know if it is in the filament?

 

I was thinking about worn-out white teflon couplers, but from what you said, I think you already replaced them, so that can't be the problem anymore? Idem for worn-out feeder wheels, clogged nozzles, etc.

 

[9thoracle 3]

Wow time just flew by lol

I actually had a chance to try that just last week. I tried some gcode from home at work and it resulted in the same thing. 

I havent yet tried gcode from work on the printer at home though.

 

I am going to try lighter rolls of material on the machines at work too just to double check, since they both have fresh 3kg rolls on aftermarket roll holders. I don't expect this to change anything though since I used the same roll holder at home and havent had issues but I know there could be more friction somewhere. 

My last ditch effort may be to buy new motherboards for the machines at work :/

[kwill5800 2]

i'm having a similar problem. Try turning your model cooling fans off. The first layer is by default no cooling but every layer after that is usually cooled that may be the problem. I'm not sure how to fix it though. I have a very similar setup as you, upgraded 2 to +. except i have a bondtech qr. 

Edited January 5, 2021 by kwill5800

[9thoracle 3]

Tried all of the suggestions here and still never had any luck. 

I ended up "fixing" the problem by turning the extrusion rate percentages up in Cura. 

Not a clean fix so I am not a very happy camper. 

I also bought new motherboards and lots of new parts trying to make sure it wasnt a mainboard or hardware issue. 
Given that I have also recently discovered that "spiralize outer contour" seems to also be broken, Im losing confidence in the people working on the Cura software as of late.