To get success in FDM printing, each and every printer part should be in a healthy state as they all contribute to model creation. Of all parts, Nozzle plays a vital role and forms a medium through which melted filament is extruded forming an object.
Printer’s extrusion is highly dependent on the Nozzle. The malfunctioning of the Nozzle may lead to many printing problems. The efficiency and life span of the nozzle is dependent on its Diameter, Supported Materials.etc
Nozzles undergo degradation as they are used. In the long run, they get filled with dirt and get clogged. Thus a regular cleaning of the Nozzle is important so that it functions well with other components in the extruder assembly. This also can boos the Nozzle lifespan.
In the article below, we will present the detailed methods of how to clean your 3D Printer Nozzle and also the preventive steps to avoid such future problems.
What Causes the Clogging of 3D Printer Nozzle?
Incorrect Nozzle Height
Nozzle height refers to the gap between the Nozzle tip and print surface. This is also called Z-Coordinate and supervises the final print output. If the distance between Nozzle and printing surface is too high, then filament gets cooled down before it sits on the previous layer. Cooled filament does not stick or mold well with the print surface resulting in a defective structure.
On the contrary, if the distance between Print Surface and Nozzle tip is too less, then there will not be enough space for the proper extrusion. The result is odd structure.
In extreme cases, too little space causes the filament to be pushed back into the nozzle due to the nozzle scraping the print surface. This leads to the problem called Retrograde Extrusion when the stubborn filament clogs the Nozzle.
Therefore, one should set the correct Nozzle height. Recommended height should be equal or smaller than that of nozzle diameter. This causes the extruder to put pressure and presses lightly for proper structure formation.
Incorrect Temperature Values
Temperature settings are at the core in preventing the Nozzle clogging and important to know.
Temperature values vary for different types of filaments. For PLA, the temperature values are from 180 to 225 Degree Celsius. Nylon filaments can be printed at temperatures higher than PLA.
When high temperature filaments are printed at lower heat, it doesn’t get fully melted (liquified) and strucks inside the nozzle. This causes clogging in the nozzle.
On the other hand, if the temperature is set too high, it melts the filament before entering the nozzle. This heats up the entire extruder assembly and higher parts. This is called the Heat Creep Effect.
When material is liquified, more pressure is needed to extrude and this causes the motor to get overloaded and stops functioning. Sometimes, the material can also crystallize and clogs in the Nozzle.
With practice, you will get a hang of right temperature settings for the used filaments to produce best results.
When you want to change the filament to another type, remove all the residues left by the previous filament inside the nozzle. This ensures that only new filament is present inside compatible to the set temperature.
Ensure to change the filament at the right temperature and do not force or put high pressure while changing.
Market is filled up with alluring filaments from different local manufacturers at very affordable prices. This is attracting many new users who are beginning their 3D printing journey and trying out different print experiments.
As always, quality demands money and quality filaments are expensive. Cheap filaments are low in quality while affecting the printing quality and causing printing problems, particularly nozzle jam.
Low-quality filaments will not have fixed diameter and tolerances throughout. It varies at different points
When the strand diameter varies, the melting point temperature also varies. This obstructs the filament flowing evenly and cleanly through the nozzle and spoils the print quality. Many low quality filaments contain unwanted ingredients and this results in Nozzle clogging.
So, be careful with mass selling low quality materials which imitate the real brands products characteristics at lower prices. These also contain less additives affecting the layer adhesion.
Do your quota of research before buying any non-branded or unknown filaments. Check their user reviews, ratings and still if you are doubtful, go for proven filament brands, even if they are expensive. You can also manually measure the filament diameter at different points using a caliper gauge. If the diameter varies, better avoid using it to prevent problems
Filament Dust and Dirt
When printing with low quality filaments, they contain dirty and dusty particles which travel through the extruder and nozzle. These get melted and carbonized in the nozzle and eventually harden overtime.
Carbonization causes the formation of the hard layer inside the nozzle, narrowing the filament flow and complete blockage.
Nozzle blockages cannot be completely eliminated. You should learn to live with them as they are obvious when printing with large volumes or large parts. They can be reduced by protecting filaments from dust and moisture by placing them in Vacuum or plastic bags. Do a manual check if there are any gross dust particles before printing.
Many times, these dusts may also accumulate while spraying varnish to the printed object. These sprays will get accumulated inside the parts of the 3d printer including Nozzle. If you want to paint, then do it away from 3d printer. Prefer a different room.
Printer Off After Printing:
This is one of the usual scenarios in which a nozzle gets blocked. Let’s say you are printing something and the current job gets completed. But you are not there in front of the printer and it turns off. This turning off of a printer will dry out the filament in the nozzle and cause blockage.
Hence it is important to configure the printer to stay warm or maintain its minimum temperature after the completion of the current job. This keeps the filament in its fluid or soft state.
Clogged Nozzle Symptoms:
The Nozzle when it gets clogged can be clearly understood by its symptoms. We are listing out some of the symptoms as below:
Repeated Feed / Flow Rate Adjustment:
When the situation arises that you have to adjust the flow rates again and again, this shows that the Nozzle is getting clogged by some particles. This repeated flow setting is not necessary when Nozzle is in healthy state.
When the Nozzle is clogged, the extrusion will not happen properly and inconsistencies can be seen right from the first layer of the printing process.
The driver motor that pushes the filament cannot keep up with its normal rotation and starts jumping backward. This is due to the lack of free movement inside the extruder.
When you see the dust being accumulated in the extruder assembly especially near motor, filament pathways, then it is the time to clean everything including the Nozzle.
Scraping / Rubbing Sound:
This sound is the direct result of clogged nozzle. It happens when the extruder grinds the plastic due to less flow rate in the Nozzle.
- Filament is not Flowing out: If you observe that filament is not flowing out even after it is heated and melted to an appropriate temperature then Nozzle is clogged. Another sign of clogged Nozzle is that the filament wont flow evenly, it comes in curls and curves. The filament flow is interrupted totally.
- Faulty Printed Object: You could see thinnings, sometimes even holes, edges are not clear and borders are blurred.
- Clicking Sound in Extruder: This clicking sound indicates that the gears are trying to push the filament and there is no space for the filament to flow producing “Clicking” sound.
- Nozzle Picks up Extruded Material: This happens when the extruder travels across the layers and picks up an already extruded material. This is also caused when the bed is not leveled and incorrect z co-ordinate values.
- Poor Extrusion Flow: When your printer is unable to extrude the filament evenly due to blockage of Nozzle, it results in inconsistent extrusion. When this happens, it bursts out filament balls and sometimes no filament at all. This is sometimes caused by Moisture Filament and problems in stepper motors too.
How to Clean the Outside Portion of Nozzle?
Method 1: Wipe the nozzle with soft cloth or tissue paper when it is cooled. This will bring out debris that is not heat resistant.
Method 2: Many times hardened material deposits are formed outside the nozzle due to previously picked extruded material. When this happens, then heating the nozzle upto 200 deg c and removing them with Needles and nose pliers.
How to Clean Your Nozzle?
For cleaning the Nozzle, many people use different methods. Of all, the most popular one is heating the Nozzle to high temperatures and pushing the filament through.
You can make use of Needle to do this and it comes in a Nozzle cleaning kit.
Nozzle Cleaning Kit
You can buy some good Nozzle cleaning kit from Amazon such as MIKA3D Nozzle Cleaning Kit. It contains 27 needles and 2 precise tweezers to put you out from a Nozzle cleaning headache.
3D Printer Nozzle Cleaning Tool Kit – 0.4mm 0.35mm Needles Tweezers Filament Clog Cleaner Accessories Part Drill Bits 27pcs Mika3D (Misc.)
You can use the Needles in this kit to clean the Nozzle hole by heating it to high temperatures. Once you heat the Nozzle, the filament residues within the Nozzle melt and needle insertion can push out the blockages.
3D Printer Nozzle Cleaning Brush
To clean the Nozzle rigorously, use a copper toothbrush to bring out all the dust particles and blockages from the Nozzle.
BCZAMD Imdinnogo 3D Printer Nozzle Cleaning Brass Wire Toothbrush Tool Brass Brush Handle Hot End Cleaning Toothbrush (2Pcs)
This brush is very handy and easily holdable while cleaning the Nozzle surface and sides. This brush remains usable even if the wires get deformed.
Cleaning the Nozzle
Till now, you have learnt how to recognize the blocked Nozzle, how these occur and steps to prevent it.
In Spite of these, if your Nozzle is blocked and nothing is working. What to do?
We have enlisted the different methods to clean the Nozzle and you can use them one after the other or repeat any one method as you like.
These methods, if followed properly, will not damage your Nozzle. Methods will vary based on the blockage severity.
Filament Pushing Through
Many times, the improper prints will not always block the Nozzle completely. Rather, only slight deposits will form inside the and around the Nozzle.
This method employs using a white ABS or Nylon as cleaning filament rather than waiting for the cleaning filament.
- Step 1: Heat up the nozzle to 200°C i.e the melting temperature of the filament.
- Step 2: Take out the filament from Nozzle
- Step 3: Now clean the outer area of the Nozzle with a paper/towel.
- Step 4: Start pushing the filament manually into the nozzle hole. Keep pushing as long as it goes or until some extrusion happens.
- Step 5: Take out the filament again.
- Step 6: Cut the dirty end of the filament which has catched all the debris inside the Nozzle
- Step 7: Repeat steps 4 to 6 until the filament comes out white as it is.
This is a manual method of removing the blockages from the Nozzle using Needle. This can be adopted for both Cold and Hot nozzles.
Heat up the Nozzle temperature to a point that melts the filament residues in the Nozzle. Now insert a needle into the Nozzle and push it until the residues come out. During your next print, a few more left out particles will be pushed out.
Many 3d companies supply Nozzle cleaning kits along with 3d printers. You can also buy them separately. Cleaning kits are also produced by many manufacturers and you can choose them based on their quality, user ratings.etc
These kits contain needles, tweezers, pliers and other cleaning tools. Use these kits if none of the household remedies work for you.
Ensure to choose the needle size not greater than Nozzle diameter opening. If you choose a higher size, then you may widen the opening and damage the Nozzle permanently.
Cleaning with Acetone:
Acetone is a chemical that can dissolve the blocked filament particles inside the Nozzle. You can remove the Nozzle and immerse in Acetone for sometime and them push out the debris using a Needle or Guitar String.
You can buy this Acetone Solution.
This method works by feeding the filament into the extruder / Nozzle and pulling out quickly again. There is a difference between filament insertion and pulling it out. There are many kinds of pulls, here we will describe the “Atomic Pull” which is suitable only for a bowden type extruder.
Here, there is no need of cleaning filament instead use the regular printing filament to clean the Nozzle. First, heat the filament to its melting temperature, switch off the heat and pull the filament out shortly before it gets solidified.
Working method: First, remove the Bowden House Clamp and set the temperature 30 degrees higher than filament used. Now insert a hand length of filament which should be fully white. Keep pushing until you reach a point where you cant push it anymore. Now adjust the Nozzle temperature as per the below values based on the type of the filament you are using and wait until these values are obtained:
- For Nylon 145 DegC
- For ABS 110 DegC
- For PLA 90 DegC
Once this temperature is attained, immediately pull out the Filament from the extruder with a steady jerk. Don’t apply too much force. The strand will come out with slight adhesive resistance.
Now dismantle the Nozzle and immerse it in a container which has undiluted Acetone. Soak the Nozzle for 24 hours and keep shaking the Nozzle often to loosen the dust. You could also use Needle to remove dirt while soaking until all the dirt comes out.
Now check the pulled out filament, if the tip is dirty and dark, then the Nozzle is still blocked. Repeat the same steps until you see the white filament as it is.
If you are finding it difficult to pull the filament, then raise the temperature so that filament can be easily loosened. Now repeat the same procedure until the strand is clean.
This method is used to remove really stubborn blockages and heavily hardened deposits inside the Nozzle. This is done at very high temperatures.
Switch on and heat the printer to 250 deg C for 3 to 5 minutes. Now use ABS /Nylon filament and push it through the Nozzle hole.
As ABS & Nylon are heat resistant, they attract the filament residues by loosening and melting them at high temperatures. Now, cool down the temperature so that the nylon/ABS gets solid. Then start heating again to 130 to 150 Deg C and pull the filament strand with a jerk. This Jerk movement has brought this name to this method.
This is an emergency method and involves the application of uncontrolled heat manually and forcefully.
First, remove the Nozzle and hold it with the pliers against the highly burning gas fire/ blowtorch/ hot air dryer. Hold the Nozzle in the downward direction so that the Fire can push out any dust inside the Nozzle.
As you hold the fire, the deposits will blow by opening the blockage. You can hold the Nozzle towards the light source and see if light can get through.
If the Nozzle is still blocked, then hold it to the flame again and pierce the Nozzle opening with Needle. This loosens the stuck particles. When this happens, hit the Nozzle firmly onto the solid surface so that blocked particles fall as lumps.
Use Cleaning Filaments:
Usage of the cleaning filaments is another method of keeping Nozzle healthy without blockages.
Cleaning filaments are made with a material that has adhesion to attract the dust and debris in the filament pathways. Once the dust and deposits are attracted, the residues can be manually pulled clearing the blockages.
It is recommended to use Cleaning Filaments quite often to prevent the Nozzle Blockage problems. Once the Nozzle is blocked completely, then even the best cleaning filament can’t help.
Cleaning filaments method can be effective with some pressure flow. These filaments are expensive than the normal ones. However, only a small amount is needed to clean.
A 50g of Cleaning filament can be used to clean 70 to 100 times which is a great mileage.
Best Cleaning Filament for 3D Printer
Cleaning Filament by NovaMaker
Novamaker Cleaning Filament comes in vacuum sealed state surrounded by desiccant packs to keep it dry. When loaded on to the 3d printer, it can clean the 3d Printer amazingly. This cleaning filament highly stable to heat and can withstand temperature upto 150-260 deg c without any issues.
Novamaker filament is made with slightly high viscosity which helps it to come out without getting stuck inside the nozzle. This avoids further jamming and instead cleans the Nozzle in and out.
Usage of cleaning needles along with this cleaning filament can do wonders and keep your nozzle clog free. This is especially useful when you switch between different types of filaments with different temperature levels.
Clean the Nozzle and printer every 3 months with Cleaning filament and needles as a regular maintenance to keep the Nozzle clog free.
eSun Cleaning Filament
eSUN has a cleaning filament which is named as eSUN 3d 2.85mm. This filament effectively cleans the nozzle by easily passing through it.
This filament has a good adhesion quality which is capable of pulling out any dust or residues that clog the extruder/nozzle while cleaning. It can clean at temperatures ranging from 150 to 270 deg C. The higher the temperature, more effectively accumulated particles will come out with this filament.
Sometimes, even after following all cleaning tips for Nozzle and extruder, still the nozzle cannot be restored. A point arrives where its efficiency drops significantly and produces unsatisfactory prints. This is an indication to replace the Nozzle. Buying a new Nozzle is the only viable option.
As a bonus, we’ve included some checklist of cleaning SOP’s in this article along with how frequently you should perform those to keep your Nozzle and printer clean.
This simple list of SOP’s have greatly benefited many users and kept them aloof from Nozzle clogging problems. If you print regularly, then this checklist of much more helpful.
- Before using the printer, wipe out the dust particles, debris and filament residues.
- Clean the nozzles with needles and cleaning filament before every print.
- Ensure the proper movements of the parts in all axes
- Check the printing profiles and ensure correct values.
- If you are not going to use the printer for the next few days, dismantle the filament from the 3D printer, clean the nozzle with needle, toothbrush or cloth. You can also use paper clip/guitar string/toothpicks
- Use a fine spatula and clean the print bed by rinsing with lukewarm water.
- Ensure proper calibration of the printer while nozzle is removed for cleaning purpose.
- Clean the Nozzle roughly using steel needles/ paper clip/ guitar string / tooth pick.
- Perform a cleanup using cleaning filaments
- Total recalibration of the printer.
- Update the software
- Apply grease and oils to moving parts, bearings, rods.etc
- Wipe out previous lubricants from spindles and re-apply fresh.
- Clean the entire extruder assembly.
- Ensure the proper cabling between the main board and other parts.
Nozzle Replacement / Upgradation
When you see that cleaning procedures are not restoring the Nozzle function and it has significantly degraded even after following all the above listed SOP’s then it is time to replace the Nozzle with a new one.
As we know, Nozzles vary by their material, diameter and the filament size they can handle. These attributes determine what Nozzle can handle print-wise and the printing output. Many abrasive filaments such as glow-in-the-dark or Wood filaments can significantly degrade the Nozzle life.
In the next section, we will dive deep into 2 factors that are important while replacing the 3D Printer Nozzle.
These 2 important factors are
- Material / filament type
Diameter of Nozzle:
A Nozzle with 0.2mm diameter has a very small hole and prints objects with great detail. It is best suited for miniatures and takes a long time for printing. The printed object contains more print lines that makes the object weak.
The 0.4 mm Nozzle size is the mid way between 0.2 & 1.0 mm. It offers good strength and less print time than 0.2mm.
This is the higher diameter of the Nozzle that allows the printing to be faster. Objects printed with this Nozzle are strong due to fewer print lines. The downside is that it doesn’t offer great print detail.
How to Clean Nozzle Using Failed ABS or PLA Prints?
Cleaning using ABS Failed Print:
First heat the Nozzle to 240 deg c. Take the failed ABS print and push it against the Nozzle hole. Now, let the Nozzle cool down for a minute. Once it is cooled slightly, pull the failed ABS and this clears the Nozzle hole of dust.
Cleaning using PLA Failed Print:
Heat the Nozzle to 70 Deg C, push the failed PLA print into the Nozzle hole. Let the Nozzle cool down slightly and now pull with tweezers/pliers. Advantage with PLA is that it gets softer when heated and easy to pull of making the hotend clean.
Ender 3 Nozzle Cleaning:
To clean the Ender 3 Nozzle in a better way, you need to dismantle and take it out by opening the fan shroud. This makes the Nozzle view very clear and now clean with an Acupuncture needle. This breaks the accumulated particles inside the Nozzle.
Now use the highest filament size the Nozzle supports and start pushing it through the Nozzle hole to bring out the broken particles inside the Nozzle.
Another method is to remove the Nozzle from the printer and heat it up with a hot gun to soften the accumulated particles. Now place the filament and push it inside the Nozzle. Keep pushing by lowering the temperature and continue this cold pull until filament starts coming as cleanly as the input side.
How Frequently Should You Clean 3D Nozzles?
There is no predefined frequency for cleaning the Nozzle. You can do this proactively when Nozzle looks dirty or 3 months once as regular maintenance. Many 3D users rarely clean their Nozzles, but are still able to print without any problems.
Nozzle life depends on printing frequency, type of material you are printing and how frequently you are cleaning the Nozzle.
Brass Nozzles exhibit longer life especially with PLA at 70 deg C while ensuring the proper bed levels.
Experienced Project Engineer with a demonstrated history of working in the field of Product Design & Development industry in Mechanical Engineering. Skilled in 3D Printing and Re engineering Technologies with CATIA V5 , Materials Science, Finite Element Analysis (FEA), Mimics, ANSYS Workbench and Casting Simulation software. Strong engineering professional with a Master’s Degree focused in Industrial Metallurgy from PSG College of Technology, Coimbatore.