3D printer nozzle clogged? ➡️ This is how you solve the problem

If the filament comes out of the nozzle unevenly or not at all, the assumption is that the nozzle is clogged. In this post, I explain what you have to do if the nozzle is clogged.

How do you recognize a clogged nozzle?

A clogged or dirty nozzle in 3D printing can show up in a number of ways. Here are some signs:

• No filament flow: No filament comes out of the nozzle even though the printer is running.
• Irregular filament flow: The filament comes out of the nozzle at irregular intervals or suddenly stops flowing.
• Uneven Layers: The printed layers are uneven or have holes or voids.
• Rough Surfaces: The printed surface is rough or uneven when the model should be smooth.
• Crackling noises: The printer is making unusual noises, specifically a crackling noise.
• Stringing: Increased stringing of the filament can be caused by deposits on the nozzle, among other things.

If you suspect the nozzle is clogged, you should stop 3D printing immediately and clean the nozzle to avoid further problems!

Clogged Nozzle: The Most Common Reasons with Solution

Before you immediately bring the needle and solvent to remove the supposed blockage, you should first find out the cause. Most of the time, the problem is either that the nozzle is too small for the filament or that the slicer settings are incorrect. So you should check that first and also clean the nozzle. If the problem persists after this, you can find more possible causes and the appropriate solution here.

Incorrect printer settings

Problem:

In the slicer (the program in which all printer settings are defined), you enter the diameter of the nozzle used, among other things. This information is important for the printer to regulate the amount of filament to print. It can easily happen that incorrect information is given here and e.g. For example, programmed for a 0.4mm nozzle when printing with a 0.6mm nozzle. Even this difference of 0.2 mm can make a huge difference because the printer pushes too much filament in relation to the size of the nozzle. The result: the pressure will stop after a certain time and no more filament will come out of the nozzle.

Solution:

Check in the slicer whether the correct diameter is specified for the nozzle. If not, correct the settings.

Nozzle diameter is too small

Problem:

The nozzle can clog if its diameter is too small for the filament to be printed. This is particularly common with wood filament : because there are small wood particles in the filament that require more space. The diameter of the nozzle must therefore be larger here (at least 0.6 mm).

Solution:

Check that the diameter of the nozzle used meets the requirements of the filament used. You can find the recommendation for the nozzle size in the filament manufacturer's specifications.

Printing temperature too low

Problem:

If the temperature of the filament is set too low, it can also lead to clogging of the nozzle - because then the filament can become too viscous and accumulate in the nozzle.

Solution:

Check in the slicer whether the correct printing temperature is set for the filament. You can find the recommended temperature in the information provided by the filament manufacturer. If the temperature is not set correctly, correct the settings.

Dirt and dust in the nozzle

Problem:

Dirt and dust can enter the 3D printer through the air or build up on the filament itself. In the nozzle, the impurities sooner or later lead to blockages.

Solution:

It goes without saying that a dirty nozzle must be cleaned. You can find out how to do this in the article "Clearing a clogged nozzle: Here's how [7 effective methods]".

Damaged or worn nozzle

Problem:

A damaged or worn nozzle can restrict the flow of filament. Damage is caused, for example, by a hard object or improper handling; Abrasion from long-term use or from printing with abrasive filament (e.g. carbon fiber reinforced filament).

Solution:

Replace the nozzle, making sure that the new nozzle is suitable for the printer and filament used. Regular nozzle inspection and gentle handling will help minimize damage and wear and prolong nozzle life.

Excessive heat

Problem:

If the 3D printer gets too hot, the filament in the nozzle can melt quickly and unevenly, and if it cools down quickly and hardens afterwards, it can clog the nozzle. This usually happens when the temperature of the nozzle is set too high in relation to the melting point of the filament, or the printer runs continuously for too long.

Solution:

Check in the slicer whether the correct printing temperature is set for the filament. You can find the recommended temperature in the information provided by the filament manufacturer. If the temperature is not set correctly, correct the settings. Also, be careful not to leave the printer running continuously for too long , especially if it's being used for long print jobs. By the way, you can use special temperature sensors to control and regulate the temperature of the nozzle. These (relatively inexpensive) electronic components are placed near the nozzle and are programmed to keep the temperature at a constant level.

Contaminated or inferior filament

Problem:

Filaments can become contaminated during manufacture, storage or when used in the 3D printer, e.g. B. absorb dust, dirt, oil or moisture, which can clog the nozzle. Moisture in the filament in particular can lead to gases when heated in the nozzle, which causes the filament to swell and clump.

Even inferior quality filaments can form clumps or knots if they have uneven diameters or poor material properties that make it difficult to flow smoothly through the nozzle.

Solution:

Use high-quality filament (e.g. Vision 3D Filament ), clean it carefully before use and store it in a dry place.

Troubleshooting a clogged nozzle - step by step

Here is the recommended procedure to diagnose and fix the cause of a clogged nozzle:

1. Check the settings in the slicer (nozzle diameter and print temperature)
2. Check that the diameter of the nozzle meets the filament requirements
3. Check filament cleanliness and quality
4. Check the printer temperature using a temperature sensor
5. Inspect nozzle and clean or replace depending on condition

Clean clogged nozzle

Of course, a clogged nozzle must be cleaned before you can continue printing. Ideally, you should clean them regularly to remove accumulated dirt and dust and prevent clogging.

There are several methods of cleaning the nozzle, including:

• ColdPull
• needle
• solvent

You can find an overview of all methods and detailed step-by-step instructions in our article “Cleaning the nozzle – this is how it works ”.

What to do if the nozzle is constantly clogged?

Over time, filament residue and dust can collect in the nozzle and clog it, which is why the nozzle should be cleaned from time to time. But if it keeps clogging despite cleaning, there is probably a fundamental problem behind it. Maybe you chose a nozzle that is too small for the filament or wrong settings in the slicer; 3D printing therefore takes place under the wrong conditions. However, it could also be due to wear or damage to the nozzle - so check its condition carefully and replace it if necessary.

George from Vision 3D