<p>This is very likely under extrusion caused by your feeder pressing down too hard onto the filament. If the feeder presses the filament very hard it then gets squished a bit, this is not causing much issues when you're only feeding in one direction as the drive gear is still pulling on fresh filament and shoving the squished part down at a steady rate. BUT once you got retractions things get awful as the squished filament then gets retracted and fed again at the same pace but due to the elongation at a smaller rate of material causing underextrusion.</p>

<p>You can either trade it in to some overextrusion by adjusting the extra length on restart setting, retract a shorter piece of filament (like only retract half a mm or something) or loosen the feeder so it doesn't squish down on the filament as hard.</p>

CC BY-SA 4.0
2019-06-11T14:45:08.347Z
Decreasing the retraction helped me in a simular situation
edosoft
CC BY-SA 3.0
2017-07-17T14:21:09.120Z
2017-07-17T14:21:09.120Z
bardiir
<p>If the problem occurs most when you are doing the most advance/retract cycles, the problem is likely with your advance/retract settings.</p>

<p>Have you tried cutting each of them in half and executing the same gcode?</p>

CC BY-SA 3.0
2017-07-20T16:33:16.183Z
2017-07-20T16:33:16.183Z
Davo
<p><strong>It definitely looks like under extrusion.</strong>  </p>

<ol>
<li>First thing I would check is the filament feeder to make sure it has
a good grip in the filament.</li>
<li>After that I would do another print to see if the problem is repeatable.</li>
</ol>

<p>If it doesn't repeat, it may have been </p>

<ul>
<li>A temporarily clogged nozzle</li>
<li>The filament was undersized in that segment and the filament feeder lost its grip.</li>
<li>The extruder got to cold for some reason in that segment and the feeder couldn't push the material through the extruder fast enough.</li>
</ul>

<p>If it does repeat:</p>

<ul>
<li>Re-inspect the filament feeder</li>
<li>Try increasing the the extruder temp to say, 225.</li>
<li>Try turning off retraction to see if it is related to those settings.</li>
</ul>

CC BY-SA 3.0
2017-07-15T17:29:20.450Z
2017-07-20T16:08:20.397Z
2017-07-20T16:08:20.397Z
markshancock
<p>Testing my new Wanhao i3+. PLA plastic(Wanhao), basic normal quality settings in Cura (I guess 0.1 mm layer, 40 mm/s speed, 60c bed temp, 200c extruder temp). After 1.5 hours of printing quality degraded, it makes some loose structure. </p>

<p>Edit:
After finish I noticed that problem exists only in layers where it cycles printing/no printing. There is no problem on layers where it print continuously.</p>

<p>What is the reason can be and how can I fix that?</p>

<p><a href="https://i.sstatic.net/W90dj.jpg" rel="noreferrer"><img src="https://i.sstatic.net/W90dj.jpg" alt="enter image description here"></a></p>

CC BY-SA 3.0
2017-07-13T12:27:08.230Z
If the problem occurs most when you are doing the most advance/retract cycles, the problem is likely with your advance/retract settings.
Davo
<pla><print-quality><wanhao>
After 1.5 hours of printing quality degraded
Dork
# After 1.5 hours of printing quality degraded

(Asked by: username_0 on 2017-07-12)

Testing my new Wanhao i3+. PLA plastic(Wanhao), basic normal quality settings in Cura (I guess 0.1 mm layer, 40 mm/s speed, 60c bed temp, 200c extruder temp). After 1.5 hours of printing quality degraded, it makes some loose structure.

Edit:
After finish I noticed that problem exists only in layers where it cycles printing/no printing. There is no problem on layers where it print continuously.

What is the reason can be and how can I fix that?

[![enter image description here](https://i.sstatic.net/W90dj.jpg)](https://i.sstatic.net/W90dj.jpg)

**Tags:** pla, print-quality, wanhao
> **Comments:**
> **username_1**: If the problem occurs most when you are doing the most advance/retract cycles, the problem is likely with your advance/retract settings.  

---

## 3 answers

### Answer by username_2 on 2017-07-17. Score: 3

This is very likely under extrusion caused by your feeder pressing down too hard onto the filament. If the feeder presses the filament very hard it then gets squished a bit, this is not causing much issues when you're only feeding in one direction as the drive gear is still pulling on fresh filament and shoving the squished part down at a steady rate. BUT once you got retractions things get awful as the squished filament then gets retracted and fed again at the same pace but due to the elongation at a smaller rate of material causing underextrusion.

You can either trade it in to some overextrusion by adjusting the extra length on restart setting, retract a shorter piece of filament (like only retract half a mm or something) or loosen the feeder so it doesn't squish down on the filament as hard.

> **Comments:**
> **username_3**: Decreasing the retraction helped me in a simular situation  

---

### Answer by username_1 on 2017-07-20. Score: 3

If the problem occurs most when you are doing the most advance/retract cycles, the problem is likely with your advance/retract settings.

Have you tried cutting each of them in half and executing the same gcode?


---

### Answer by username_4 on 2017-07-15. Score: 2

**It definitely looks like under extrusion.**

1. First thing I would check is the filament feeder to make sure it has
   a good grip in the filament.
2. After that I would do another print to see if the problem is repeatable.

If it doesn't repeat, it may have been

* A temporarily clogged nozzle
* The filament was undersized in that segment and the filament feeder lost its grip.
* The extruder got to cold for some reason in that segment and the feeder couldn't push the material through the extruder fast enough.

If it does repeat:

* Re-inspect the filament feeder
* Try increasing the the extruder temp to say, 225.
* Try turning off retraction to see if it is related to those settings.


---

