<p>So I finally managed to solve the issue. It was indeed (massive) under extrusion (during the whole print).</p>
<p><strong>Let me first explain why this does not show up in the first layers</strong> (according to what I read somewhere else online):</p>
<p>The under-extrusion issue is already present in the first layers, but it does not become visible due to the print bed giving enough &quot;counterpressure&quot;. This means that the material is squished between the bed and the nozzle, making up for the under-extrusion. After a few layers, this does not happen anymore, and the lack of flow begins to show.</p>
<p><strong>How I solved the issue:</strong></p>
<p>I made an extrusion calibration according to this <a href="https://forum.snapmaker.com/t/extruder-calibration-a-must/7724/32?page=2" rel="nofollow noreferrer">Snapmaker forum article</a>. Basically, I measured off 100 mm from my extruder input, marked the 100 mm mark with a black sharpie and told the printer to extrude (what he believes to be) 100 mm of filament. This turned out the be not 100 mm but rather approximately 25 mm (which means that the printer is extruding about 25 % of what it is supposed to do). Then I went and changed the printer's flow rate to four times the current rate, which solved the issue.</p>
<p><strong>Why was the extruder so bad?</strong></p>
<p>I don't know exactly, but I had to hot-glue two parts in my extruder together because they were freely moving against each other and the motor's torque was not transferred to the extruder's axle. Could be I introduced some friction this way, but I saw the same under-extrusion issues before I noticed this issue, so I don't really know.</p>

CC BY-SA 4.0
2021-12-14T18:27:53.477Z
Glad you sorted it out, but, not the preferred way to do this. It could be that the extruder is just too broken to reuse. Also make sure you slice for the correct filament diameter and that the steps per mm are correct for the extruder. You can get the current value from the menu/display, once this is correct you would never have to use large flow modifiers, this is not what that modifier is supposed to be used for.
0scar
CC BY-SA 4.0
2021-12-14T13:19:07.090Z
2021-12-14T15:56:05.170Z
2021-12-14T15:56:05.170Z
Philipp Wacker
<p>I am struggling with a problem. In short: I have managed to set up my Ender 3 V2 in such a way that the first few layers print (almost) perfectly, but after the first few layers (do not know exactly, but maybe after 2-4 layers) I am having massive issues with (maybe) under extrusion, with the filament coming out in a &quot;pearl necklace&quot; shape. Here are a few images for illustration:</p>
<p>First layer of bed level test (<a href="https://www.chepclub.com/bed-level.html" rel="nofollow noreferrer">this source</a>). The filament is nicely flat on the print bed, also it still sticks when I rub it with my fingers.</p>
<p><a href="https://i.sstatic.net/SxuXU.jpg" rel="nofollow noreferrer" title="Photo of bed leveling calibration print"><img src="https://i.sstatic.net/SxuXU.jpg" alt="Photo of bed leveling calibration print" title="Photo of bed leveling calibration print" /></a></p>
<p>Third/fourth layer of bed level test. The upper layers are of this &quot;pearl necklace&quot; shape (maybe there is an established name for that?), i.e. something like ---o---o---o---</p>
<p><a href="https://i.sstatic.net/oxxdi.jpg" rel="nofollow noreferrer" title="Photo of calibration print with bumps after the first few layers"><img src="https://i.sstatic.net/oxxdi.jpg" alt="Photo of calibration print with bumps after the first few layers" title="Photo of calibration print with bumps after the first few layers" /></a></p>
<p>Similarly with the Benchy. I printed the first few layers. The first layer is quite clean and you can make out the font nicely (this turned upside down, i.e. you're looking at it from the bottom).</p>
<p><a href="https://i.sstatic.net/BydP6.jpg" rel="nofollow noreferrer" title="Bottom of 3DBenchy showing printing errors"><img src="https://i.sstatic.net/BydP6.jpg" alt="Bottom of 3DBenchy showing printing errors" title="Bottom of 3DBenchy showing printing errors" /></a></p>
<p>After the first few layers, the shape of the filament is again this problematic pearl necklace shape (you can already see that at the boundary of the previous image, where you can see those layers).</p>
<p><a href="https://i.sstatic.net/jX4me.jpg" rel="nofollow noreferrer" title="Top view of first few millimeters of 3DBenchy showing printing errors"><img src="https://i.sstatic.net/jX4me.jpg" alt="Top view of first few millimeters of 3DBenchy showing printing errors" title="Top view of first few millimeters of 3DBenchy showing printing errors" /></a></p>
<p>I'm totally at loss at how to resolve this issue. How can the print quality degrade so much after the first few layers? I don't even have any good hypotheses (temperature dropping after some time? Z-offset needs to be adjusted for every layer? Hot end starts clogging during the print?).</p>

CC BY-SA 4.0
2021-12-13T23:37:45.173Z
What has changed recently? It looks like massive under extrusion.
0scar
CC BY-SA 4.0
2021-12-14T13:09:39.247Z
I am a new user (I have obtained the printer second hand and I had no prior experience). So I haven't had a successful print before.
Philipp Wacker
<creality-ender-3><print-quality><underextrusion>
Massive blobs/under extrusion/"pearl necklace" only after first few layers (Ender 3 V2)
Philipp Wacker
# Massive blobs/under extrusion/"pearl necklace" only after first few layers (Ender 3 V2)

(Asked by: username_0 on 2021-12-13)

I am struggling with a problem. In short: I have managed to set up my Ender 3 V2 in such a way that the first few layers print (almost) perfectly, but after the first few layers (do not know exactly, but maybe after 2-4 layers) I am having massive issues with (maybe) under extrusion, with the filament coming out in a "pearl necklace" shape. Here are a few images for illustration:

First layer of bed level test ([this source](https://www.chepclub.com/bed-level.html)). The filament is nicely flat on the print bed, also it still sticks when I rub it with my fingers.

[![Photo of bed leveling calibration print](https://i.sstatic.net/SxuXU.jpg "Photo of bed leveling calibration print")](https://i.sstatic.net/SxuXU.jpg "Photo of bed leveling calibration print")

Third/fourth layer of bed level test. The upper layers are of this "pearl necklace" shape (maybe there is an established name for that?), i.e. something like ---o---o---o---

[![Photo of calibration print with bumps after the first few layers](https://i.sstatic.net/oxxdi.jpg "Photo of calibration print with bumps after the first few layers")](https://i.sstatic.net/oxxdi.jpg "Photo of calibration print with bumps after the first few layers")

Similarly with the Benchy. I printed the first few layers. The first layer is quite clean and you can make out the font nicely (this turned upside down, i.e. you're looking at it from the bottom).

[![Bottom of 3DBenchy showing printing errors](https://i.sstatic.net/BydP6.jpg "Bottom of 3DBenchy showing printing errors")](https://i.sstatic.net/BydP6.jpg "Bottom of 3DBenchy showing printing errors")

After the first few layers, the shape of the filament is again this problematic pearl necklace shape (you can already see that at the boundary of the previous image, where you can see those layers).

[![Top view of first few millimeters of 3DBenchy showing printing errors](https://i.sstatic.net/jX4me.jpg "Top view of first few millimeters of 3DBenchy showing printing errors")](https://i.sstatic.net/jX4me.jpg "Top view of first few millimeters of 3DBenchy showing printing errors")

I'm totally at loss at how to resolve this issue. How can the print quality degrade so much after the first few layers? I don't even have any good hypotheses (temperature dropping after some time? Z-offset needs to be adjusted for every layer? Hot end starts clogging during the print?).

**Tags:** creality-ender-3, print-quality, underextrusion
> **Comments:**
> **username_1**: What has changed recently? It looks like massive under extrusion.  
> **username_0**: I am a new user (I have obtained the printer second hand and I had no prior experience). So I haven't had a successful print before.  

---

## 1 answers

### Answer by username_0 on 2021-12-14. Score: 1

So I finally managed to solve the issue. It was indeed (massive) under extrusion (during the whole print).

**Let me first explain why this does not show up in the first layers** (according to what I read somewhere else online):

The under-extrusion issue is already present in the first layers, but it does not become visible due to the print bed giving enough "counterpressure". This means that the material is squished between the bed and the nozzle, making up for the under-extrusion. After a few layers, this does not happen anymore, and the lack of flow begins to show.

**How I solved the issue:**

I made an extrusion calibration according to this [Snapmaker forum article](https://forum.snapmaker.com/t/extruder-calibration-a-must/7724/32?page=2). Basically, I measured off 100 mm from my extruder input, marked the 100 mm mark with a black sharpie and told the printer to extrude (what he believes to be) 100 mm of filament. This turned out the be not 100 mm but rather approximately 25 mm (which means that the printer is extruding about 25 % of what it is supposed to do). Then I went and changed the printer's flow rate to four times the current rate, which solved the issue.

**Why was the extruder so bad?**

I don't know exactly, but I had to hot-glue two parts in my extruder together because they were freely moving against each other and the motor's torque was not transferred to the extruder's axle. Could be I introduced some friction this way, but I saw the same under-extrusion issues before I noticed this issue, so I don't really know.

> **Comments:**
> **username_1**: Glad you sorted it out, but, not the preferred way to do this. It could be that the extruder is just too broken to reuse. Also make sure you slice for the correct filament diameter and that the steps per mm are correct for the extruder. You can get the current value from the menu/display, once this is correct you would never have to use large flow modifiers, this is not what that modifier is supposed to be used for.  

---

