Why Does The Filament Stick To The Nozzle? Factors & Solutions!


3D printing can be complex even for seasoned professionals. Between the materials and the printer a lot could go wrong. Plastic is the king of 3D print materials with 90 percent of prints being made from the plastic filament. Composites are the second most used with metals, ceramics and glass making up the top five. 

Plastics are popular because they are cheap, easy to work with and fit the requirements of most prints. While plastics are the easiest to work with they can present a few challenges. 

Plastics are sticky when melted. This is necessary for the filament to adhere to the print bed and for the layers in your model to stick together. But you want the plastic to stick only where it is supposed to. There are many times when it does not.

26 percent of 3D printer users say they print every day. If you’re one of those in that category or if you are printing less frequently, it is highly likely you will experience filament sticking to the nozzle of your printer. 


On a side note! If you’re looking for a reliable and high-quality 3D printer, we highly recommend the Official Creality Ender 3 V2 Upgraded 3D Printer (Amazon Link).

This printer is an upgraded version of the popular Ender 3 model, with a range of new features and improvements that make it even easier and more convenient to use.

The Ender 3 V2 is an excellent choice for beginners, kids, and experienced users.


 

Today we look at how or why that happens and what steps to take when it does. By the end of this article you should be able to troubleshoot and fix a jammed printer yourself.

How Do You Stop a Filament from Getting Stuck?

There are three steps to preventing filament jam. The first is ensuring the filament is properly stored so it is dry and dust free. The second is to use the right size diameter and appropriate printer settings for that specific filament. The third is to use a clean nozzle. 

Over the next few sections we will cover how you can implement these steps to prevent or fix printer jam.

For more on this, we highly recommend that you check out our post ” What Nozzle Size Should You Use For 3D Printing? (Thin VS Thick)

Why Does Filament Keep Getting Stuck? (Factors Listed)

Filament frequently gets stuck at one of two points in a printer. It can either stick on the roll or at the extruder. Typically, filament jam happens at the extruder. This is caused by tangles in the filament, swelling, heat creep or a clogged nozzle.

Filament roll has lost its tension

A new roll of filament is tense. Loosening the end of the roll causes it to lose some of its tension. This can cause your filament to get tangled and stuck on the roll. You can avoid this by making sure the roll stays taut and securing the end of your filament to the spool and not the remaining filament roll when you’re not printing.

Problems with the spool holder

A printer can also jam if there is a problem with the spool holder. This might be because the holder is in the wrong place for example. The spool holder has to be positioned well in terms of angle, alignment and orientation to allow the stepper motor to easily draw filament from it.

Wet filament

When filament gets wet it swells up and may not fit properly through the extruder. The way to fix this is to dry the filament before using it. You should also make sure to store filament in airtight containers to prevent moisture absorption. 

Heat creep

A printer has a hot and cold end. The hot end is the nozzle where the plastic filament is melted before being extruded. Heat creep is when the filament melts before it gets to the nozzle in what is supposed to be the cold end of the extruder. 

PLA is especially prone to heat creep because of its low extrusion temperature. If the filament is melting prematurely it could be because of a faulty cooling fan, heat sink, or heat block. Check to see they are working properly and securely fixed.

If you’re using a print enclosure you should try removing a panel to allow for more airflow. 

Also check out our post What Is A Heat Break For 3D Printing & Is it required! Heat Creep Explained

Filament size

One simple but easy to overlook factor that can cause the filament to get stuck is using the wrong filament size. Filament has a diameter of 1.75 or 2.85mm. Printers will use one or the other but not both.

Also check out our post Can You Use 2.85mm Filament In A 1.75mm Printer? Does Filament Size Matter?

How Do You Keep a Filament from Sticking to The Nozzle?

Filament sticking to the nozzle can be remedied by adjusting the printing temperature, changing the nozzle or nozzle height, and cleaning the filament itself. It largely depends on the initial diagnosis of what is causing the filament to stick to the nozzle.

Low hot end temperature

If the hot end temperature is too low, the filament will not be liquid enough to flow through the nozzle. This is why it’s important to check the extrusion temperature of the filament you are printing with. Here’s a guide to help you.

FILAMENTEXTRUSION TEMPERATURE °C
PLA180 – 230
ABS210 – 250
PETG (PET, PETT)220 – 250
TPE, TPU, TPC (Flexible)210 – 230
Nylon (PA)240 – 260
PC (Polycarbonate)270 – 310
Wood-Filled190 – 250
Metal-Filled200 – 220
Polycarbonate270 – 310
ASA240 – 260
Ceramic255 – 275
Conductive 210 – 230
PolyPropylene235 – 265
PVA160 – 200
List of Filaments Types and their Extrusion Temperatures

Adjust the layer height

The layer height is the distance between the nozzle and the print bed. If the nozzle is too far from the print bed, there isn’t enough pressure between them so instead of adhering to the bed, the filament wraps around the nozzle. 

The layer height can also be too small. In this case the nozzle is too close to the print bed so there’s not enough room to allow the filament to extrude. Source

Do not use dirty filament

If the filament has collected dust, for example if it hasn’t been stored properly and has been out in the open for a long time, this can clog up the nozzle. Again this underscores the importance of properly storing your filament between use.

We also highly recommend that you check out our post “How Long Do 3D Printer Nozzles Last? Factors And Signs of Deterioration!

How to Unclog 3d Printer Nozzle ?

One way to unclog your nozzle is to use a needle, wire or any material thin and rigid enough to push through the nozzle to get rid of the obstruction. 

The alternative if this does not work is to use the cold pull method. Here you take a high temperature filament like Nylon and push it up through the nozzle. You then heat the Nylon to its extrusion temperature before letting it cool. The idea is to make the obstruction stick to the Nylon then pull it out.

Why Is Your 3D Printer Dragging Filament? (Quick FIX)

A printer dragging filament may be the result of wrong temperature or z-axis settings. The first thing to do is make sure the nozzle is at the right temperature. It should not be too high or too low. A thermocouple probe or laser thermometer can be used to check the temperature.

The second step would be to check the z-axis. The z-axis controls the distance between the nozzle and the print bed. Adjusting the z-axis brings the nozzle closer or further away from the print bed. 

sherifjallad

I am a very well experienced techie civil engineer who's extensively interested in 3D printing technology and even more captivated by the potential of 3D printing livable structures

Recent Posts