How to fix Under – Extrusion

Under-extrusion is when the printer is unable to supply the right amount of material. You’ll know if your printer is under-extruding as you’ll see missing layers, very thin layers, or layers that have random dots and holes in them. The extrusion of filament is too less than normal.

Solution

Please follow the following instructions to fix the under – extrusion.

            1)  The Feeder [Bowden Mechanism]

1. The materials grind in the feeder.
   
2. The feeder makes tak - tak sound.
   
3. The feeder is not with proper tension or the feeder is got broken.
   

How to predict whether the tension is proper or not?

This can easily be diagnosed by taking the material out of the 3D printer and checking if there are visible marks on the material.

1. Marks on material mean good feeder tension.
   
2. No marks on material mean too low feeder tension.
   
3. Grinding of the material means too high feeder tension. 
   

2)  Bowden Tube

The material has passed the feeder, it will be forwarded through the Bowden tube. It’s possible the material could experience friction in the Bowden tube, leading to under-extrusion.

Sometimes if the Bowden tube is not get locked properly with a notch on the e3d also leads to under–extrusion.

      3)  Clogging

After printing for a long time or switching materials from one to another. The hot end nozzle should be cleaned at proper Temperature.

The following temperature for each material for cleaning nozzle is mentioned below.

PLA - 210 to 240 degrees at hot end recommended.

ABS - 240 degrees at the hot end recommended.

HIPS -230 degrees at the hot end recommended.

PETG – 235 degrees at the hot end recommended.

For cleaning the nozzle first preheat the nozzle to the corresponding temperature and unload the filament from the nozzle. Use a long T shape 1.5mm Allen key to clean the nozzle from the top.