UMO+ Under extrusion..... I have tried everything I can think of. PLEASE HELP

[lcrrick 0]

I have had a UMO+ go from great prints to Extreme under Extruded overnight.

I have had great success with the trouble shooting area of the Ultimaker site in the past. NO LUCK this time. I have tried everything on there as well as some other suggestions from the "google"

I have only messed with PLA and Carbon Fiber

What I have tried with NO change:

1. Change Settings Hotter extruder and cooler extruder

2. Change material, different PLA, then Carbon Fiber

3. New extruder tip (three different ones)

4. New insulator

5. Whole new Hot end

6. Cleaned Feeder(bowden) tube(did not replace)

7. Hotter bed (didn't figure that would do anything and it didn't)

8. Leveled the bed countless times......

I am not sure what to try next. It seems that If I run at the very top of the temp spread for PLA it is a bit better but still no where near the quality of the prints this unit made when new at lower temps (i.e.: 225c vs 200c when new)

PLEASE help if anyone has any suggestions.

[gr5 2,170]

How much CF filament? I would look carefully at the splined (or is it gnurled?) bolt that pushes the filament. The tiny pyramidal peaks can get worn down such that the tip of each "pyramid" is now rounded and doesn't grip the filament well.

One test is to engage the stepper by moving it a little with the filament only a few inches past the feeder. Then pull downard hard. It should hold on with about 10 pounds of force before slipping. You can also test with a scale and weight and vice grip the weights to some filament. Or you can just hole a 5 pound weight for a few minutes to get a feel for it and then pull down with that force on the filament.

10 pounds is potentially enough to tip the printer so you probably will need to hold the printer with one hand and pull with the other.

[gr5 2,170]

Here's my test on the UM2. But I have a UMO also and other people have tested their UMO. Both machines (even the old black feeder on UM2) typically go to about 5kg or about 10 pounds when the spring is nice and tight.

[amedee 349]

I think as well that if the hot-end side is OK, then the culprit is probably the extruder.

In addition to what @gr5 said, also look at the plastic wheel which pushes the filament against the bolt. It tends to deform and becomes ineffective. Best is then to replace it by a bearing.

[neotko 1,417]

Just to remove the stuff one doesn't check, are you sure your hotend is perfectly assembled?

https://ultimaker.com/en/community/37096-trying-to-fix-our-schools-original-cannot-figure-out-whats-going-on-with-our-hot-end

Because if you ever had a leak of carbon between the peek/barrel, since it can become carbon and become really hard, you might have particles inside that are obstructing the path.

I know from personal experience (8kilos of CF from formfutura) that I had to toss the barrel after a leak from coupler deformations).

To check this is very easy, you just need to get a perfect atomic, then this isn't the issue.

[tommyph1208 55]

Checking if the feeder is the problem is pretty easy... just bring the hotend to specified temp for your material of choice and push some filament through by hand... Is this doable? Does the filament flow out of the nozzle in a nice uniform little string? If yes, then your hotend is fine and its your feeder you have to start working on.

If you can't push filament through by hand, neither can your feeder, and so your hotend must be the problem.

Edited March 15, 2017 by Guest