<p>It turns out that it was caused by the filament being ground at regular intervals. I solved it by lowering the printing speed (I did change the bowden tube to a 1.75 mm one though). Still working on fully tuning this printer.</p>

CC BY-SA 4.0
2023-03-25T21:42:15.080Z
2023-03-25T21:42:15.080Z
Gart Hondo
<p>You have a number of &quot;red flags&quot; in your process. Using filament of a size different from the design's filament specification would be one of them. Bubbles in the filament may mean moisture, regardless of the storage method. Reddit contains a number of posts from users who have presented before and after (dehydration) photos of parts created from new-from-the-box filament. You suggest that the motor does not slip during prints, but there's also reference that it happens in other actions.</p>
<p>In order to pin down a solution, address the filament size by using the correct filament. Use a dehydrator to ensure that the filament contains no moisture. Using correct diameter filament will also cover the slipping extruder.</p>
<p>Once you address these issues and tune the printer appropriately, you may discover that using the smaller diameter filament is going to be a compromise.</p>

CC BY-SA 4.0
2023-03-11T20:19:14.077Z
I used some several-year-old 2.85 mm PLA I had lying around, and the extrusion seems fine, even though it is really wet. It's super weird that the 1.75 mm didn't work properly, as I had successfully printed a benchy just the other week. I'm going to keep trying to see if I can get the 1.75 mm to work, as I only have a few meters of the really old 2.85 mm while I have several rolls of 1.75 mm.

However, the slipping extruder has always been an issue with this printer, regardless of the filament diameter or tension I try.
Gart Hondo
CC BY-SA 4.0
2023-03-12T00:41:04.120Z
Would there be a way to solve this issue while using 1.75 mm? Adafruit provides a guide for how to do this successfully, (https://learn.adafruit.com/using-1-dot-75mm-filament-on-ultimaker-2), but doesn't have any mention for problems like this.
Gart Hondo
CC BY-SA 4.0
2023-03-12T01:10:40.350Z
The first thought that pops into my alleged mind, after reading the linked site you've provided is to change the bowden tube to 1.75 compatible sized tubing. This will reduce or remove some of the compression artifacts and reduce the question count by at least one. In order to accomplish this, it might also be necessary to remove and replace the existing push-to-connect fittings for the 2.85 mm tube.
fred_dot_u
CC BY-SA 4.0
2023-03-13T05:56:09.653Z
Ok, I will try a new bowden tube. Any suggestions for slicing differently? It also seems that it only occurs on full 100% layers, not layers with infill.
Gart Hondo
CC BY-SA 4.0
2023-03-13T08:54:23.923Z
Before you move on to changing slicer settings, it would be advisable to calibrate your e-steps for that printer. This will ensure that when the slicer commands a specific volume of filament to be extruded that the result matches the command.
fred_dot_u
CC BY-SA 4.0
2023-03-13T22:59:59.957Z
I calibrated all of the axes and updated the post with an image of the XYZ 20mm calibration cube.
Gart Hondo
CC BY-SA 4.0
2023-03-11T11:30:48.670Z
2023-03-11T11:30:48.670Z
fred_dot_u
<p>I'm working on tuning an old Ultimaker 2 Go, and I'm having some weird extrusion issues. The printer uses a Bowden extruder. Extrusion seems to increase and decrease. I don't think it is the filament quality, as I am using Prusament PLA that I am storing in a dark closet inside a sealed bag with silica gel. I also did multiple cold pulls until no debris. I do notice that sometimes the filament appears to bubble. The extruding motor also sometimes slips/snaps back while changing filament, but not during prints.</p>
<p>However, I am using 1.75 mm filament while the printer is designed for 2.85 mm. In order to do this, I followed some steps I found from All3D.</p>
<p>I also have a small PVC jig to hold the filament, but I think it turns pretty well and shouldn't be the issue.</p>
<p>Filament: PLA, Temp: 215 °C, Slicer: Cura</p>
<p><img src="https://i.sstatic.net/9mGf2.jpg" alt="1" /></p>
<p>*Update:
I calibrated the e-steps and all of the axes, but the problem still remains.</p>
<p>I also printed an XYZ cube, and there is a line right under the letters X and Y. It also appears that the extrusion is more inconsistent outside of the letters. I'm pretty sure this issue is related to the weird first-layer pattern, or this is just a cooling issue due to varying cooling %.</p>
<p>Filament: PLA, Temp: 215 °C, Slicer: PrusaSlicer</p>
<p><img src="https://i.sstatic.net/8YrlZ.jpg" alt="1" /></p>

<extrusion><bowden><ultimaker>
Weird Pattern First Layer Extrusion
Gart Hondo
# Weird Pattern First Layer Extrusion

(Asked by: username_0 on 2023-03-11)

I'm working on tuning an old Ultimaker 2 Go, and I'm having some weird extrusion issues. The printer uses a Bowden extruder. Extrusion seems to increase and decrease. I don't think it is the filament quality, as I am using Prusament PLA that I am storing in a dark closet inside a sealed bag with silica gel. I also did multiple cold pulls until no debris. I do notice that sometimes the filament appears to bubble. The extruding motor also sometimes slips/snaps back while changing filament, but not during prints.

However, I am using 1.75 mm filament while the printer is designed for 2.85 mm. In order to do this, I followed some steps I found from All3D.

I also have a small PVC jig to hold the filament, but I think it turns pretty well and shouldn't be the issue.

Filament: PLA, Temp: 215 °C, Slicer: Cura

![1](https://i.sstatic.net/9mGf2.jpg)

\*Update:
I calibrated the e-steps and all of the axes, but the problem still remains.

I also printed an XYZ cube, and there is a line right under the letters X and Y. It also appears that the extrusion is more inconsistent outside of the letters. I'm pretty sure this issue is related to the weird first-layer pattern, or this is just a cooling issue due to varying cooling %.

Filament: PLA, Temp: 215 °C, Slicer: PrusaSlicer

![1](https://i.sstatic.net/8YrlZ.jpg)

**Tags:** extrusion, bowden, ultimaker

---

## 2 answers

### Answer by username_0 on 2023-03-25. Score: 2 | Accepted answer

It turns out that it was caused by the filament being ground at regular intervals. I solved it by lowering the printing speed (I did change the bowden tube to a 1.75 mm one though). Still working on fully tuning this printer.


---

### Answer by username_1 on 2023-03-11. Score: 0

You have a number of "red flags" in your process. Using filament of a size different from the design's filament specification would be one of them. Bubbles in the filament may mean moisture, regardless of the storage method. Reddit contains a number of posts from users who have presented before and after (dehydration) photos of parts created from new-from-the-box filament. You suggest that the motor does not slip during prints, but there's also reference that it happens in other actions.

In order to pin down a solution, address the filament size by using the correct filament. Use a dehydrator to ensure that the filament contains no moisture. Using correct diameter filament will also cover the slipping extruder.

Once you address these issues and tune the printer appropriately, you may discover that using the smaller diameter filament is going to be a compromise.

> **Comments:**
> **username_0**: I used some several-year-old 2.85 mm PLA I had lying around, and the extrusion seems fine, even though it is really wet. It's super weird that the 1.75 mm didn't work properly, as I had successfully printed a benchy just the other week. I'm going to keep trying to see if I can get the 1.75 mm to work, as I only have a few meters of the really old 2.85 mm while I have several rolls of 1.75 mm.  However, the slipping extruder has always been an issue with this printer, regardless of the filament diameter or tension I try.  
> **username_0**: Would there be a way to solve this issue while using 1.75 mm? Adafruit provides a guide for how to do this successfully, (https://learn.adafruit.com/using-1-dot-75mm-filament-on-ultimaker-2), but doesn't have any mention for problems like this.  
> **username_1**: The first thought that pops into my alleged mind, after reading the linked site you've provided is to change the bowden tube to 1.75 compatible sized tubing. This will reduce or remove some of the compression artifacts and reduce the question count by at least one. In order to accomplish this, it might also be necessary to remove and replace the existing push-to-connect fittings for the 2.85 mm tube.  
> **username_0**: Ok, I will try a new bowden tube. Any suggestions for slicing differently? It also seems that it only occurs on full 100% layers, not layers with infill.  
> **username_1**: Before you move on to changing slicer settings, it would be advisable to calibrate your e-steps for that printer. This will ensure that when the slicer commands a specific volume of filament to be extruded that the result matches the command.  
> **username_0**: I calibrated all of the axes and updated the post with an image of the XYZ 20mm calibration cube.  

---

