Elephant foot is a common 3D printing issue

3D printing elephant foot is a common issue that most 3D printer users will have experienced. Typically caused by excessive heat or poor nozzle calibration, the issue can be solved in several ways.

Troubleshooting the 3D Printing Elephant Foot Phenomenon

<p dir="ltr" id="isPasted">FDM 3D printing is certainly not a silent process: it is perfectly normal for your 3D printer to whirr and even buzz as the printhead moves and filament is extruded onto the build plate. In fact, desktop 3D printers can produce up to 50 decibels of sound when in operation—similar to the amount of noise a relatively quiet fridge produces.[1] However, if you start to notice clicking sounds that seem to be interrupting the regular hum of your machine, then you could be dealing with a problem.</p><p dir="ltr">Unfortunately, if your 3D printer extruder starts to make a clicking noise, it’s not just your ears that will be bothered. Clicking is indicative of a bigger problem, which can compromise the quality of your 3D prints. A clicking extruder can be a sign of filament extrusion inconsistencies, such as under extrusion or a clogged nozzle.</p><h2 dir="ltr">What causes extruder skipping and clicking</h2><p dir="ltr">The first step to fixing a clicking extruder is to figure out what’s causing it. In general, the extruder will start clicking or skipping if the extruder gears—which are responsible for feeding the filament into the hot end—struggle to do their job. The clicking noise itself comes from the stepper motor, which has to use greater force to turn the gears, and then compensates for the added force and subsequent pressure by skipping back.&nbsp;</p><p dir="ltr">There are several culprits that can cause extruder gear issues. We’ll take you through the main ones and how to solve each one.</p><h3 dir="ltr">Low temperature</h3><p dir="ltr">Temperature plays a huge role in the 3D printing process: setting the print temperature too high can make the filament melt too quickly, causing issues like <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank" rel="noopener noreferrer">oozing and stringing</a>. If the print temperature is too low, the filament won’t melt at a sufficient rate, which can lead to nozzle clogs. If the nozzle becomes clogged, the printer extruder will struggle to feed the filament through, which can ultimately lead to skipping.&nbsp;</p><p dir="ltr">Fortunately, there is an easy fix for this problem: all you have to do is gradually raise the print temperature—by about 5 °C—until the filament starts to flow more smoothly. It is also important to remember that each type of filament has an optimal print temperature. So if you’re working with <a href="https://www.wevolver.com/article/abs-print-temperature-considerations-nozzle-bed-enclosure" rel="noopener noreferrer" target="_blank">ABS</a> after having printed <a href="https://www.wevolver.com/article/pla-bed-temperature-print-temperature-settings" rel="noopener noreferrer" target="_blank">PLA</a>, you’ll need to adjust the print settings accordingly.&nbsp;</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/abs-print-temperature-considerations-nozzle-bed-enclosure" rel="noopener noreferrer" target="_blank">ABS print temperature considerations</a></strong></p><h3 dir="ltr">Low nozzle position</h3><p dir="ltr">When temperature doesn’t seem to be the issue but you are still experiencing extruder clicking from a partially clogged nozzle, nozzle height could be the reason. If the nozzle is positioned too close to the print bed, the filament won’t extrude onto the build surface properly because the nozzle will effectively be squishing it. Not only does this cause under extrusion for your prints, it also causes nozzle jams because the melted filament sticks to the outside of the nozzle.&nbsp;</p><p dir="ltr">If you notice the combination of a clicking extruder and filament buildup on the outside of the nozzle, your best bet is to level your 3D printer bed. Some 3D printers have automatic bed leveling, but for those with manual machines, the easiest way to level your bed is to use a standard sheet of paper. Move the nozzle to one corner of the build plate and place a piece of paper under it, lower the nozzle until it just touches the paper (the paper won’t slide out, but will be able to move). Repeat this for every corner of the build surface.&nbsp;</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 758px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjc3NjY1MDIyODM3LW5vb3psZS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" width="624" height="459" class="fr-fic fr-dii" alt="3D printer nozzle"><span class="fr-inner">Clean your nozzle inside and out to ensure a consistent filament feed rate and minimize the risk of clicking.</span></span></span></p><p dir="ltr"><span style='font-family: "PT Sans", serif; font-size: 22px; font-weight: 700; background-color: transparent; color: rgb(0, 0, 0);'>Nozzle blockage</span></p><p dir="ltr">If your 3D printer has become clogged for whatever reason, it can cause extruder clicking. If this happens, you will have to find the source of the blockage—such as adjusting the temperature—but you will also have to unclog the nozzle. If you’re dealing with a partial clog (i.e. some filament is still flowing through), you can use a cleaning filament to remove the clog or a wire brush to clean filament buildup from the surface of the nozzle.&nbsp;</p><p dir="ltr">If the nozzle is showing signs of a full clog, there are a few techniques that help to remove the blockage. You can insert a thin wire or needle (smaller than the diameter of your nozzle) into the heated nozzle to break up the filament. This will allow the debris to flow out and clear the block.&nbsp;</p><p dir="ltr">Another popular method to unclog a 3D printer nozzle is the cold pull. To do the cold pull, heat up the 3D printer extruder (to between 200-250 °C depending on the filament) and push a length of filament into the print head. You’ll then let the print head cool until the filament is solidified. After that, reheat the 3D printer to a lower temperature (115°C) and when it reaches 90 °C, rapidly yank the filament out of the extruder. The filament should have bonded with the buildup and been pulled out along with the filament.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-nozzles-and-prevent-clogs" target="_blank">How to Clean 3D Printer Nozzles and Prevent Clogs</a></strong></p><h3 dir="ltr">PTFE tubing failure</h3><p dir="ltr">Bowden tube 3D printers rely on a PTFE tube to direct and feed filament into the print head. When the tubing system is working correctly, the filament should move through the tube seamlessly, without any friction. Extrusion problems can arise, however, if there is too much friction inside the bowden tube.&nbsp;</p><p><span style="background-color: transparent;">There are a couple things that can be causing this friction. For one, a bowden tube that is too small for the filament diameter. In general, the bowden tube should be just marginally larger in diameter than your filament: you want it to move smoothly through the tube, but you also don’t want too much space for the filament to flex and bend. Secondly, any debris that builds up inside the tube, such as dust, can increase the friction. This can slow the filament down and create a buildup of pressure in the extrusion mechanism, leading to clicking.&nbsp;</span></p><p dir="ltr">To ensure that the bowden tube is not causing any extrusion issues, clean it regularly by removing it from the 3D printer and pushing a small piece of cotton or sponge through the length of it using filament. If that doesn’t solve the friction problem, and your bowden tube appears to be dented or bent, you can always replace the tube.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/direct-drive-vs-bowden-extruder-for-3d-printing" target="_blank">Direct Drive vs Bowden Extruder for 3D Printing</a></strong></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 758px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjc3NjY1MTA4NjI2LTNkX3ByaW50ZXIuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" width="624" height="459" class="fr-fic fr-dii" alt="Bowden tube 3D printer"><span class="fr-inner">Friction build up inside a bowden tube can slow filament down, causing stepper motors to overcompensate and skip.</span></span></span></p><p dir="ltr"><span style='font-family: "PT Sans", serif; font-size: 22px; font-weight: 700; background-color: transparent; color: rgb(0, 0, 0);'>&nbsp; &nbsp; Extruder spring tension</span></p><p dir="ltr">In the FDM 3D printing process, filament is propelled through the extruder with the help of either a single gear or dual gears. The movement of the gears is powered by a stepper motor, but the extruder also relies on a certain degree of tension to ensure that the gears make contact with and grip the filament in order to feed it into the printhead at a reliable pace. This tension is created by the extruder spring.</p><p dir="ltr">If the extruder spring tension is too high, the gear teeth will press into the filament too much, causing filament deformation. The high tension can also impede the feed rate of the filament, which in turn causes the stepper motor to exert more force and even start to skip. The skipping motor is what creates the clicking sound in your extruder.</p><p dir="ltr">If the tension of the spring is too low, the extruder gears won’t sufficiently grip the filament, which will require the extruder to use greater force to feed the filament into the printhead. The added friction can lead to problems like filament degradation and grinding noises. [2] All that to say, finding the correct degree of tension for your extruder spring is vital to achieving the highest quality prints. On most 3D printers, spring tension can be adjusted using a screw or knob. You can always start by loosening the tension completely and gradually tightening it until clicking stops.</p><h3 dir="ltr">&nbsp; &nbsp; Idler wheel too tight</h3><p dir="ltr">This troubleshooting is applicable to single-gear extruders. The idler wheel, or idler roller, is a round bearing that helps to guide the filament along the single gear into the printhead. If the idler wheel is tightened too much, the result will be similar to high spring tension: the gear will start to crush the filament, which can lead to extrusion troubles and stepper motor skipping.&nbsp;</p><p dir="ltr">You can tell your extruder’s idler wheel is well calibrated by checking the thermoplastic filament as it is threaded through. Small gear tooth marks on the filament’s surface are a good sign: they show the gears are making sufficient grip to move the filament at pace. If you notice any crushing or deformed filament, loosen the idler wheel tension slightly. This can help reduce the risk of clicking and failed prints.</p><h3 dir="ltr">&nbsp; &nbsp; Faulty extruder motor</h3><p dir="ltr">Another possible cause for extruder clicking is the stepper motor. If the stepper motor is poorly calibrated or is not connected to a reliable power source, it can result in filament feeding inconsistencies and, consequently, clicking. This issue is rarer than the aforementioned ones, so try adjusting your settings before making major hardware changes.</p><p dir="ltr">If you suspect a faulty stepper motor is behind your 3D printer problems, first check the motor’s wiring to make sure nothing is out of place. You might have to replace your printer’s motor if there are wiring problems. If you notice your stepper motor is overheating, adding a heat sink can help to mitigate the build up of heat and prolong the life of the motor. You can buy adhesive heat sinks to stick directly onto the extrusion mechanism. It’s worth bearing in mind that a heat sink will add weight to the extruder. In direct drive systems, this means your 3D printer’s motor will require more force to move the printhead across the build platform.</p><h2 dir="ltr">Key Takeaways</h2><p dir="ltr">Clicking noises from your 3D printer should be reason for concern. The noises indicate that something is amiss or not properly calibrated. Luckily most causes of extruder clicking have a straightforward solution. Here’s what we covered in this troubleshooting piece:</p><ul><li dir="ltr"><p dir="ltr">One of the most common causes of extruder clicking is related to temperature settings. If the print temperature is too low, unmelted filament will start to clog the nozzle and prevent consistent filament feeding. Increase the print temperature gradually to see if it helps.</p></li><li dir="ltr"><p dir="ltr">Leveling the print bed and ensuring proper calibration can minimize the risks of nozzle jams and help solve extruder skipping.&nbsp;</p></li><li dir="ltr"><p dir="ltr">If there is too much friction in your printer’s bowden tube, the stepper motor will have to exert more force to feed filament into the printhead. Clean the bowden tube frequently or replace it if it becomes dented.</p></li><li dir="ltr"><p dir="ltr">Finding the optimal extruder spring tension and idler wheel tightness can promote a more consistent filament feed rate, which in turn reduces the risk of clicking, because the filament will keep up with the stepper motor.</p></li><li dir="ltr"><p dir="ltr">Stepper motor failure is a rarer occurrence but can create clicking noises. If this is the case, you may have to replace your extruder’s stepper motor, or the extruder overall.</p></li></ul><h2 dir="ltr">References</h2><p dir="ltr">[1] “What Is 50 Decibels Compared To Other dB”. Decibel Pro. [ Accessed February 2023] <a href="https://decibelpro.app/blog/what-is-50-decibels/" target="_blank">https://decibelpro.app/blog/what-is-50-decibels/</a>&nbsp;</p><p dir="ltr">[2] “How to Set Extruder Tension”. CNC Kitchen. May 7, 2022. [Accessed February 2023] <a href="https://www.cnckitchen.com/blog/how-to-set-extruder-tension" target="_blank">https://www.cnckitchen.com/blog/how-to-set-extruder-tension</a>&nbsp;</p>

A clicking extruder is an indication something is wrong with slicer settings or 3D printer calibration

Temperature, nozzle height, and spring tension are just some of the causes of a clicking extruder. Learn how to troubleshoot this 3D printing issue.

3D Printer Extruder Clicking: 7 Fixes and Causes

<h2 dir="ltr" id="isPasted">What are the lines in a 3D print?</h2><p dir="ltr">Every 3D-printed part's surface is made up of hundreds of separate layers. If everything is in order, those layers would appear to be one continuous and smooth surface. However, if a problem arises during the printing process with only one of such layers, the fault can be quite obvious from the print's exterior. On the sidewalls of the printed components, these incorrect layers may show as lines or ridges. Frequently, the flaws would appear in a cyclic manner, meaning that the patterns will recur (i.e. once after every 10 layers).</p><h2 dir="ltr">What are the causes for these lines to appear in a 3D print?</h2><p dir="ltr">In general, such irregular lines are generated by inaccuracy or misplacement of a single layer with respect to the subsequent layers. In any case, why does this mismatch begin to form? There are a number of reasons behind it. Let’s explore these reasons and how they affect the overall process of printing:</p><h3 dir="ltr">Over-Extrusion</h3><p dir="ltr">Over-extrusion is the main reason why a 3D print has lines. There doesn't necessarily have to be significant over-extrusion; it might simply be a small amount of additional material being pushed out when the level is printing. Over extrusion is the phenomenon that occurs when the 3D printer's nozzle extrudes far more filament over the build plate. The problem, which is associated with the extruder's flow rate, can cause a variety of issues, including leaking, blobs, and threading, in addition to poor print quality as a whole and geometric error. Interestingly, over-extrusion may occur in any FDM 3D printer, regardless of the computer system or materials used.</p><p dir="ltr">Knowing when the 3D printer is over-extruding is crucial, as is acting swiftly to address the issue. Not only may excessive extrusion lead to delays and material loss, but it may also jam the nozzle of the printer.</p><h3 dir="ltr">High Temperatures</h3><p dir="ltr">The temperature being greater than it should be is most frequently the source of over-extrusion. A large temperature differential can cause the print to appear melted, whilst a tiny one will simply cause a small quantity of undesired plastic to emerge. Some individuals print at a temperature that is far higher than is necessary. Although certain PLA filaments have a melting temperature of 180 degrees Celsius, most hobbyists prefer to work at temperatures between 200 and 215 degrees.</p><p dir="ltr">There's no denying that greater temperatures can improve layer adhesion, but it also comes with a number of problems. Blobbing and gushing are two common problems that affect individuals all over the world. In order to avoid any further problems, one should try to operate at the lowest temperature practicable. However, it’s likely too low if there is under-extrusion or poor layer adherence. &nbsp;Finding the ideal setting for the printers and filaments just requires a little time and effort but it pays off in the long run.</p><h3 dir="ltr">Abrupt Temperature Changes/Fluctuations</h3><p dir="ltr">The thermistor can cause wrong temperatures sometimes leading to difficulties printing but the temperature fluctuations create an entirely new problem. The heated end's temperature is measured via a thermistor, but the temperature setting is controlled by the PID controller. Temperature changes are typically rather obvious. &nbsp;The problem arises if the temperature changes by more than 5 degrees Celsius.</p><p dir="ltr">In such a scenario, one can attempt to re-calibrate the PID controller but to do that a manual will be required for that particular printer. But, if that doesn't work, the circuit board for the printer might need changing.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 758px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjc3NDg2MDMyNDU1LXN0cmluZ2luZy5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" width="602" height="441" class="fr-fic fr-dii"><span class="fr-inner">Error in filament extruder temperature optimization</span></span></span></p><h3 dir="ltr">Mechanical Problems</h3><p dir="ltr">Z-banding refers to the presence of horizontal lines across a 3D print's casing. These designs often reoccur every few layers. Various problems can lead to z-banding, but the main cause for z-bending is a bent lead screw. A movement may severely impact the precision of the 3D print and may result in lines across the 3D print if the printer's lead screw is distorted at particular layer heights.</p><p dir="ltr">3d printer rods wear out after long continuous use and it’ll affect the z-axis functioning. This will have an impact on the printing design and result in the lining effect. Additionally, if the wheel or the belt is out of alignment the print output might experience strange lines on the sides and surface. Another mechanical issue that might cause Z-wobble and other flaws like lines on the sides of the 3D print includes slow linear bearing.</p><h3 dir="ltr">Damaged Extruder Nozzle</h3><p dir="ltr">A damaged extruder nozzle can cause prints to have a really strange horizontal pattern on every layer. This can happen when the tip of the nozzle gets scrapped. &nbsp;It gives off an intriguing feel but also has a terrible appearance. &nbsp; Two things may cause this to happen. The primary reason is that the nozzle scratches the tip off because it is very near to the bed. The second scenario is that the user unintentionally scrapes it away while attempting to clean it.</p><p dir="ltr">Always clean the nozzle with extreme caution, especially if the metal is heated and pliable. Use one of the replacement nozzles that likely came with the printer if the original gets damaged. If the nozzle is a different size then alter the <a href="https://www.wevolver.com/article/best-ender-3-pro-cura-settings-temperature-speed-retraction-more" target="_blank" rel="noopener noreferrer">slicer settings</a> to adjust to the new-sized nozzle.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 758px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjc3NDg2MTE2ODIxLWJyYXNzX25venpsZXMuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" width="602" height="441" class="fr-fic fr-dii"><span class="fr-inner">New and used brass nozzles for 3d printer</span></span></span></p><h3 dir="ltr">Printing too Quickly</h3><p dir="ltr">An automobile will slip around a turn if it is driven too rapidly. Similarly, the print's sides will be covered with extra filament if the extruder is operating too rapidly. This may occasionally be more obvious on curved sides or it may just be present on plain edges as well where it’ll extrude more material. Whatever it is, it may likely be lessened by slowing down the printing speed.</p><h3 dir="ltr">Unstable Print Surface</h3><p dir="ltr">The printing bed or the ground the printer is placed on can both be referred to as an unstable surface. Both of these can produce ringing lines. The back-and-forth motion of the printers causes vibrations that result in ringing. If it's severe indeed, it will make the prints seem dreadful. Using clamps for the printer bed could help stabilize it. The higher the prints are, the more the bed will shift while printing.</p><h3 dir="ltr">Bad Filament Diameter Quality</h3><p dir="ltr">A 3D print failure finally occurs because uneven filament diameters impact the flow rate for filament ejection, which leads to poor surface finish, extruder jams, inconsistent gaps within individual extrusions, and excessive overlapping. Also, if the filament that is being employed isn't the same diameter that the slicer expects, the print won't look as well as it should. In reality, it may result in tiny holes, missing pieces, the excessive filament in some areas, and other problems. It is crucial that the filament adheres as closely as possible to the specification.</p><h2 dir="ltr">How to fix lines on the side of 3d prints?</h2><p dir="ltr">All the fixes for the aforementioned issues, which result in lines showing up on the 3D prints, can be found in the following subsections.</p><h3 dir="ltr">Fixing Extrusion Issues</h3><p dir="ltr">Excess filament coming out when the printer is over-extruding makes the layers thicker than they should be. To resolve this issue, one can lower the filament flow rates and/or reduce the temperature of the extruder to avoid excess melting of the filament.</p><p dir="ltr">Over time, the extruder nozzle can be subject to general wear and tear and can get damaged while scraping. In such cases, it is best to replace the nozzle with a better-quality one for extended usage. If an abrasive filament is being used for printing, opting for a hardened steel nozzle would be a better option.</p><h3 dir="ltr">Fixing Temperature-Related Issues</h3><p dir="ltr">Higher temperatures make the extrusion of plastic much easier and more fluid but without much control. To fix this problem, the printer should be operated at lower temperatures. However, if the printer is under extruding then slowly increase the temperature till the optimum temperature range for the printer has been determined.</p><p dir="ltr">Another issue is abrupt temperature changes or fluctuations resulting when the PID controller is out of tune. Making sure that the controller is properly tuned with temperature variation not greater than ±2°C. Also, a brass nozzle can be utilized to avoid such fluctuations, since it provides better thermal conductivity.</p><h3 dir="ltr">Fixing Mechanical Issues</h3><p dir="ltr">Mechanical problems like bent screws, wearing rods, and linear bearing issues can lead to z-bending. Proper maintenance of these mechanical parts can help prevent this problem. However, if the lead screw is significantly bent then it should be replaced with a high-quality screw. Also, lubricating the printer rod and properly adjusting the belt and wheel can smoothen the movements and prevent the formation of weird lines on the prints.</p><h3 dir="ltr">Fixing Issues Related to Printing Speed</h3><p dir="ltr">When the extruder is printing too quickly, it tends to deposit extra filament material on the sides. In such a scenario, one should lower the printing speed. This’ll give the proper amount of time for layers to properly adhere. One can try changing the flow rate if it is desirable or necessary to maintain the present speed. But eventually, it gets too quick for the printer, which will lead to further problems. Reduce the printing speed if it exceeds the recommended rate for the printer or tries initially modifying the flow rate and cooling if the current speed is below that.</p><h3 dir="ltr">Fixing Filament Diameter Issues</h3><p dir="ltr">Poor-quality filaments might change the extruder's feeding pressure, which can result in lines showing on the sidewalls of the 3D print. One can buy a better quality filament from a trusted provider to avoid this issue. Also, make sure that the measured diameter of the filament is within the acceptable range of the extruder nozzle.</p><h3 dir="ltr">Fixing Issues Related to Printer’s Stability</h3><p dir="ltr">The location of the printer is also important. The printer will vibrate if the stand it's on is not solid. The printer may need some vibration-absorbing soles if the lining persists even after securing the table. They are usually available at the hardware store or can also be procured from the online marketplace. Better still, the flexible filament may be used to create them. Another thing regarding vibrations to be aware of is that the higher up a tall, narrow print is, the more oscillations it will produce. Curving the print can give greater solidity and stop the ringing effect.</p><h2 dir="ltr">Key Takeaways</h2><p dir="ltr">Most people think that layer lines present in 3D-printed components are a serious issue. The extra unwanted lines and deposits in the print ruin the quality of the overall print. One may conceal or get rid of layering lines on the 3D-printed objects in a number of ways. Starting the print at a lower temperature and having the PID controller properly adjusted can prevent the excessive melting of filaments and over-extrusions. Also, it is important to maintain all the mechanical components in top-notch condition to avoid z-bending and help maintain the quality of the 3d prints. Other aspects like printing speed, filament diameters, and stability of the printer’s base should also be carefully monitored and adjusted in order to obtain a hitch-free and good-quality 3d output.</p><h2 dir="ltr">&nbsp;References</h2><ol><li dir="ltr">Lines on the Side of Print | Simplify3D Software [Internet]. Simplify3D. 2023 [cited 2023 Feb 24]. Available from:<a href="https://www.simplify3d.com/resources/print-quality-troubleshooting/lines-on-the-side-of-print/" target="_blank">&nbsp;https://www.simplify3d.com/resources/print-quality-troubleshooting/lines-on-the-side-of-print/</a></li><li dir="ltr">Boissonneault T. Dealing with Over Extrusion in 3D Printing [Internet]. Wevolver. 2022 [cited 2023 Feb 25]. Available from:<a href="https://www.wevolver.com/article/dealing-with-over-extrusion-in-3d-printing" target="_blank">&nbsp;https://www.wevolver.com/article/dealing-with-over-extrusion-in-3d-printing</a></li><li dir="ltr">Simmons J. Why Are There Lines on the Side of Your 3D Print? [Internet]. The 3D Bros. 2023 [cited 2023 Feb 25]. Available from:<a href="https://the3dbros.com/why-are-there-lines-on-the-side-of-my-3d-print/" target="_blank">&nbsp;https://the3dbros.com/why-are-there-lines-on-the-side-of-my-3d-print/</a></li><li dir="ltr">Admin 3dfuel. Does Filament Quality Really Matter? [Internet]. 3D-Fuel. 2020 [cited 2023 Feb 26]. Available from:<a href="https://www.3dfuel.com/blogs/news/does-filament-quality-really-matter#:~:text=If%20the%20filament%20you" target="_blank">&nbsp;https://www.3dfuel.com/blogs/news/does-filament-quality-really-matter#:~:text=If%20the%20filament%20you</a></li><li dir="ltr">Jallad S. How To Get Rid Of Lines In 3D Printing, Flow Rate and Homing in 3D printing. - 3D Print Schooling [Internet]. 3dprintschooling.com. 2021 [cited 2023 Feb 26]. Available from:<a href="https://3dprintschooling.com/how-to-get-rid-of-lines-in-3d-printing-flow-rate-and-homing-in-3d-printing/" target="_blank">&nbsp;https://3dprintschooling.com/how-to-get-rid-of-lines-in-3d-printing-flow-rate-and-homing-in-3d-printing/</a></li><li dir="ltr">Dwamena M. 9 Ways How to Get Rid of Lines on the Side of 3D Prints – 3D Printerly [Internet]. 3dPrinterly. 2023 [cited 2023 Feb 26]. Available from:<a href="https://3dprinterly.com/how-to-get-rid-of-3d-print-lines/" target="_blank">&nbsp;https://3dprinterly.com/how-to-get-rid-of-3d-print-lines/</a></li><li dir="ltr">Ahmed S. A Quick Guide To 3D Printing Without Getting Layer Lines [Internet]. 3d Gear Guide. 2022 [cited 2023 Feb 26]. Available from:<a href="https://3dgearguide.com/3d-printing-without-getting-layer-lines/" target="_blank">&nbsp;https://3dgearguide.com/3d-printing-without-getting-layer-lines/</a></li></ol>

In the world of 3D printing, lines of deposited material are the key factor in disturbing quality and aesthetics of the final print. In this article we will discuss the causes of lines in 3D Prints and how they can be avoided.

Lines in 3D Prints: How to Fix Them

When bed adhesion is too strong, certain removal processes can damage the print bed.

Here are some reliable tips to follow if your 3D print simply isn't coming off the print bed and how to prevent the issue in future.

3D Print Stuck to Bed: What to do?

<p dir="ltr" id="isPasted">If you notice that there are horizontal cracks in your 3D print or that layers seem to be coming apart, particularly in the middle of a build, you are likely dealing with a problem known as 3D printing layer separation (aka delamination). In the 3D printing process, delamination is caused by poor adhesion between the layers. In other words, as each new layer is deposited, something is preventing it from fusing properly to the preceding layer, which causes it to pull apart and crack as it dries. This phenomenon can have serious consequences for not only the appearance of 3D models but also part strength and structural integrity.</p><p dir="ltr">3D printing layer separation has similarities to <a href="https://www.wevolver.com/article/3d-print-not-sticking-to-print-bed-heres-the-solution" target="_blank">first layer adhesion problems</a> (when the first layers of a build do not stick to the print bed <a href="https://www.wevolver.com/article/what-causes-3d-print-warping-and-how-to-prevent-it" target="_blank">resulting in warping</a>). For example, some of the primary causes of 3D printing layer separation are incorrect print temperature and under-extrusion. But there are also important differences between the two. In this article, we are diving into the common <a href="https://www.wevolver.com/tag/3d-printing-troubleshooting" target="_blank">3D printing problem and troubleshooting</a> delamination.&nbsp;</p><h2 dir="ltr">How to Improve Layer Adhesion</h2><p dir="ltr">There are a number of ways to improve layer adhesion and minimize the risk of 3D printing layer separation, ranging from adjusting print temperature and speed settings, to cleaning or changing nozzles, to playing with cooling settings. We outline each of these potential fixes below.&nbsp;</p><h3 dir="ltr">Increase print temperature</h3><p dir="ltr">One of the first steps to fixing delamination is to increase the print head temperature. If the print head isn’t hot enough for the type of material you are printing with, the filament won’t melt consistently, which can lead to under-extrusion and weak bonding between layers. A higher temperature will cause the filament to melt faster and result in a stronger filament flow through the nozzle. This in turn will encourage the filament layers to fuse together and create a stronger part.&nbsp;</p><p>Finding the correct print temperature depends entirely on the type of filament you are using. For example, PLA has a relatively low melting point and prints at a lower temperature than ABS. For PLA, we recommend starting off with a <a href="https://www.wevolver.com/article/pla-bed-temperature-print-temperature-settings" target="_blank">print temperature of about 210 °C</a>. If layer separation is occurring at this temperature, try increasing the hot end temperature by 5-10 degrees at a time. For ABS, the recommended range for <a href="https://www.wevolver.com/article/abs-print-temperature-considerations-nozzle-bed-enclosure" target="_blank">nozzle temperature is 220–250 °C</a>. If you are still seeing delamination within this range, gradually increase the nozzle temperature to see if layer adhesion improves.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 627px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjY1NDgxOTMyNjUwLTNkX3ByaW50ZXIuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" width="624" height="423" class="fr-fic fr-dii" alt="3D printer nozzle and blue print"><span class="fr-inner">If layers don't bond properly, it can result in cracking and structural weaknesses.</span></span></span></p><h3 dir="ltr" id="isPasted">Clean the nozzle&nbsp;</h3><p dir="ltr">As we saw, 3D printing layer separation occurs when layers of filament do not properly bond to each other. This could be due to incorrect printing temperatures, but it can also be caused by inconsistencies in extrusion. If your nozzle is under-extruding, there won’t be enough thermoplastic filament to create strong adhesion between the layers. We therefore recommend checking your 3D printer’s hotend to make sure there isn’t any plastic or dust clogging the nozzle. If there is, <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-nozzles-and-prevent-clogs" target="_blank">unclog the nozzle</a> and remove the blockage.&nbsp;</p><p dir="ltr">There are a number of ways to clean your printer’s clogged nozzle. One of the simplest methods involves inserting a fine needle or wire (smaller than the nozzle’s diameter) into the heated nozzle tip to break up any debris. You can also purchase dedicated cleaning filament, which catches any blockages and pulls them through the hot end. Other cleaning methods include the cold pull and atomic pull techniques. If these methods are insufficient, it could be time to replace the nozzle entirely. Ultimately, a clean nozzle won’t just help solve layer separation, it can also improve other 3D printing issues, <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank">such as stringing</a>.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-nozzles-and-prevent-clogs" target="_blank">How to Clean 3D Printer Nozzles and Prevent Clogs</a></strong></p><h3 dir="ltr">Decrease print speed</h3><p dir="ltr">Print speed, which refers to how quickly the printhead moves along the X and Y axes while depositing filament, has a significant impact on the quality of 3D printing.[1] While a fast print speed is often desirable, it also comes with an increased risk of issues like ringing, under-extrusion, and poor layer adhesion. These problems happen when the melting and extrusion rate of the filament can’t quite keep up with the printhead’s movement.</p><p dir="ltr">Decreasing the print speed can thus improve your 3D print outcomes. For regular prints, we recommend a print speed within the range of 50–60 mm/s. If you are experiencing delamination within this range, decrease the print speed by about 5 mm/s at a time. In general, the slower the print speed you use, the better the adhesion between layers and the stronger the final part will be. Additionally, the optimal print speed is highly dependent on the type of filament you are printing: PLA can handle faster printing speeds, while a material like TPU needs to be printed slowly (20 mm/s).</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/3d-print-speed-what-it-is-and-why-it-matters" target="_blank">3D print speed: What it is and why it matters</a></strong></p><h3 dir="ltr">Adjust flow rate</h3><p dir="ltr">Another setting that can influence inter-layer adhesion is the flow rate, or extrusion multiplier. A parameter found in slicer programs like Cura, flow rate controls how quickly filament is fed into the hot end. In general, the flow rate is linked to the print speed, so if you increase or decrease the print speed, the flow rate should adjust automatically.&nbsp;</p><p dir="ltr">If you’ve cleaned your 3D printer’s nozzle and have adjusted the print temperature and speed but are still seeing the signs of under-extrusion and poor layer adhesion, you can try adjusting the flow rate incrementally. When facing under-extrusion, you want to gradually increase the flow rate so that more material will flow through the nozzle. We should note, however, that increasing the flow rate too much can lead to other problems, namely over-extrusion and blobs.</p><h3 dir="ltr">Decrease cooling rate</h3><p dir="ltr">Layer delamination or layer splitting can also occur if the thermoplastic layers cool too quickly on the print bed and don’t have enough time to bond before the plastic solidifies. There are a couple strategies for slowing the cooling process down. For starters, using an enclosed build chamber will help ensure a more consistent print environment and slow down the filament’s rate of solidification. This not only gives each new filament layer more time to fuse with the previous layer, it can also reduce the risk of shrinking and warping. If your printer does not have an enclosure, you can make or buy one.[2]</p><p dir="ltr">If you are still seeing the signs of delamination, you can further decrease the cooling rate by lowering the printer’s cooling fan speed. We suggest doing this in increments—by 5 to 10% at a time—to see if it improves layer bonding. We should also point out that certain materials benefit from lower fan speeds, including ABS and PETG, while other materials, like PLA, can print well with a fan speed of 100%.&nbsp;</p><h3 dir="ltr">Adjust layer height</h3><p dir="ltr">Decreasing the layer thickness in your slicer software can also help to improve layer adhesion and solve delamination. In general, the layer height measurement should be smaller than the nozzle diameter.[2] This difference ensures that the nozzle puts a bit of pressure on each layer it deposits, gently squishing it and encouraging the thermoplastic to stick to the layer under it. If the layer height is too big, the surface area between the two layers will be smaller and have a weaker bond.&nbsp;</p><p dir="ltr">When setting your layer height, it should be a maximum 80% of the nozzle diameter size. For example, if you are using a 0.4 mm nozzle, the maximum layer height should be 0.32 mm.[3] With this size of nozzle, 0.2 mm is a fairly standard layer height. If this layer height isn’t solving delamination, you can try decreasing it, but if you set your layer height too small you risk other problems, like thin layers and clogged nozzles.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 627px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjY1NDgxOTYyOTk3LW5venpsZXMuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" width="624" height="459" class="fr-fic fr-dii" alt="3D printer nozzles"><span class="fr-inner">Increasing the nozzle diameter can improve inter-layer adhesion and reduce the risk of delamination.</span></span></span></p><h3 dir="ltr" id="isPasted">Increase nozzle diameter</h3><p dir="ltr">Another effective tactic for combatting layer separation is to swap out your nozzle for one with a larger diameter. A wider nozzle diameter will allow more material to flow through onto the print bed, and will result in layers with a thicker width. The wider layers can improve layer adhesion thanks to the simple fact that there is a greater surface area for the next layers to stick to.</p><p dir="ltr">Most FDM 3D printers come equipped with a 0.4 mm nozzle, so that’s likely what you’re working with. It is possible to purchase and install smaller and larger nozzles: a smaller diameter nozzle (0.2 mm) will enable you to print finer details, while a larger diameter will encourage layer adhesion and strength and can increase print speeds (this will inevitably compromise precision and the quality of details). Larger nozzles are also less prone to clogging and are suitable for specialty filaments, like fiber-reinforced materials.&nbsp;</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/nozzle-diameter-and-layer-height-explained" target="_blank">Nozzle diameter and layer height explained&nbsp;</a></strong></p><h3 dir="ltr">Proper filament storage</h3><p dir="ltr">The materials you are using to 3D print can also influence the quality of finished models, and bad quality of moisture-affected filaments can contribute to common 3D printing problems like delamination. Proper material storage and handling are therefore very important when it comes to FDM 3D printing. Hygroscopic filaments like PLA and nylon can absorb moisture from the air, which then evaporates when the filament is melted in the print head. The air bubbles created from the evaporating moisture trapped in the thermoplastic ultimately cause inconsistent extrusion, bubbling, and poor layer adhesion. To prevent this, filaments should be stored in airtight containers with desiccants. If you are concerned that your filament may have been exposed to moisture already, it is possible to dry it out before the printing. We have a <a href="https://www.wevolver.com/article/how-to-dry-filament" target="_blank">helpful guide on drying filament here</a>.</p><p dir="ltr">It is also a good idea to invest in high-quality filament from reputable manufacturers for consistent diameter, material properties, and minimal impurities. That’s because low-quality filament contains impurities or inconsistencies that can affect flow properties and bonding characteristics, leading to weak adhesion and separation. To check the quality of your 3D &nbsp;printing filament, simply measure the filament’s diameter at various points using calipers and check for visible defects or inconsistencies.&nbsp;</p><h2 dir="ltr">Key Takeaways</h2><p dir="ltr">By following these various steps (one by one because sometimes a single adjustment will solve the problem!) you should be able to overcome delamination and ensure that your prints benefit from strong bonds between layers. Here’s a rapid summary of what we covered:</p><ul><li dir="ltr"><p dir="ltr">3D printing layer separation occurs when printed layers of plastic do not fuse together properly during the printing process, causing weaknesses in the 3D printed structure.</p></li><li dir="ltr"><p dir="ltr">Increasing the print temperature can fix delamination by improving filament flow and ensuring that layers are sufficiently melted to bond together.&nbsp;</p></li><li dir="ltr"><p dir="ltr">Build up in the 3D printer nozzle can cause under-extrusion and lead to delamination. Clean your nozzle regularly to avoid this problem.</p></li><li dir="ltr"><p dir="ltr">Adjusting the print speed can also improve delamination: a slower print speed will result in stronger adhesion between layers and a stronger final part.</p></li><li dir="ltr"><p dir="ltr">&nbsp;Other factors, like flow rate, fan speed, and nozzle size can also impact the quality of inter-layer bonding.</p></li></ul><p dir="ltr">By applying the information in this article, 3D printing users can solve the issue of delamination and reduce the risk of it happening again. This ultimately will help you to achieve more consistent and reliable 3D prints.</p><h2 dir="ltr">Frequently Asked Questions (FAQs)</h2><p dir="ltr"><strong>Q: What is layer separation in 3D printing?&nbsp;</strong></p><p dir="ltr">A: Layer separation occurs when the individual layers of a 3D printed object fail to bond or adhere properly, resulting in visible gaps, cracks, or complete separation between layers.</p><p dir="ltr"><strong>Q: What causes layer separation?&nbsp;</strong></p><p dir="ltr">A: Layer separation can be caused by various things, including incorrect temperature, flow rate, speed, and cooling settings, or issues with the printer nozzle or filament.</p><p dir="ltr"><strong>Q: How can I prevent layer separation?&nbsp;</strong></p><p dir="ltr">A: To prevent layer separation, optimize print settings for the specific material, ensure proper material storage and handling, and perform regular maintenance and cleaning on the 3D printer nozzle.</p><p dir="ltr"><strong>Q: Can layer separation be fixed after a print is completed?&nbsp;</strong></p><p dir="ltr">A: In most cases, layer separation cannot be effectively fixed after a print is completed, particularly when it has a functional application. However, in some cases it is possible to minimize the signs of delamination in a 3D print. For example, applying a coating (such as <a href="https://www.wevolver.com/article/pla-smoothing" target="_blank" rel="noopener noreferrer">an epoxy resin</a>) will help smooth out the surface of the print. When using ABS, acetone can also help soften the layers and help fuse them together.&nbsp;</p><p dir="ltr"><strong>Q: Can layer separation influence the strength and integrity of a 3D printed part?&nbsp;</strong></p><p dir="ltr">A: Yes, layer separation can significantly impact the structural integrity, dimensional accuracy, and overall functionality of a 3D print, making it unsuitable for functional applications or end-use products.</p><h2 dir="ltr">References</h2><p dir="ltr">[1] Agarwal KM, Shubham P, Bhatia D, Sharma P, Vaid H, Vajpeyi R. Analyzing the impact of print parameters on dimensional variation of ABS specimens printed using fused deposition modelling (FDM). Sensors International. 2022 Jan 1;3:100149</p><p dir="ltr">[2] &nbsp;Zuza, Mikolas. How to Build a simple, cheap enclosure for your 3D printer [Internet]. Prusa Research, April 13, 2018. Available from: <a href="https://blog.prusa3d.com/cheap-simple-3d-printer-enclosure_7785/" target="_blank">https://blog.prusa3d.com/cheap-simple-3d-printer-enclosure_7785/</a>&nbsp;</p><p dir="ltr">[3] Layer Separation and Splitting [Internet] Simplify 3D, 2022. Available from: &nbsp;<a href="https://www.simplify3d.com/support/print-quality-troubleshooting/layer-separation-and-splitting/" target="_blank">https://www.simplify3d.com/support/print-quality-troubleshooting/layer-separation-and-splitting/</a></p>

Adjust temperature, speed, and cooling settings to fix delamination

The causes behind 3D printing delamination and eight ways to improve inter-layer adhesion for stronger 3D prints.

How to Fix 3D Printing Layer Separation (AKA Delamination)

<p dir="ltr" id="isPasted">If your 3D prints are coming off the print bed with oozing or drooping layers, blobs, or signs of stringing, there is a good chance you are dealing with over extrusion. Over extrusion is a common problem in fused deposition modeling (FDM) 3D printing that can have a negative impact on the structural integrity and quality of your prints. If left untreated, over extrusion can also eventually lead to 3D printer nozzle jams.&nbsp;</p><p dir="ltr">There are many things that can cause over extrusion in 3D printing—from thermoplastic filament settings and print temperature to flow rate parameters. Fortunately, there are also straightforward solutions to fix over extrusion. Keep reading this article to understand what over extrusion is, what causes it, and most importantly how to fix it.</p><h2 dir="ltr">What is Over Extrusion?&nbsp;</h2><p dir="ltr">Over extrusion is simply the phenomenon of too much filament coming out of your 3D printer nozzle onto the build platform. The issue is related to your 3D printer extruder’s flow rate and can lead to many problems, like oozing, blobs, and stringing, as well as poor overall print quality.&nbsp;</p><p dir="ltr">Additionally, over extrusion can cause dimensional inaccuracies, as the surplus material can distort the shape and size of the printed object. This can be particularly problematic for prints that require high precision, such as mechanical parts or functional prototypes. Furthermore, over extrusion can lead to structural weaknesses in the printed object. The excess material can create internal stresses within the print, which can lead to cracks and fractures under load. Notably, over extrusion is not exclusively related to specific hardware or materials: it can happen with any FDM 3D printer and filament.</p><p dir="ltr">It is very important to identify when your 3D printer is over-extruding and to fix the problem as quickly as possible. This is not only because over extrusion can lead to wasted time and materials; it can also cause your <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-nozzles-and-prevent-clogs" target="_blank">3D printer nozzle to become clogged</a>. As you can imagine, this is a slightly tricker problem to tackle.&nbsp;</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-nozzles-and-prevent-clogs" target="_blank">How to Clean 3D Printer Nozzles and Prevent Clogs</a></strong></p><h2 dir="ltr">What causes Over Extrusion?</h2><p dir="ltr">When it comes to the cause of over extrusion, there are a few possible culprits, including print temperature, filament diameter inconsistencies, and incorrect flow rate calibration.&nbsp;</p><h3 dir="ltr">Print temperature</h3><p dir="ltr">One of the most common reasons for over extrusion is that your 3D printer’s temperature settings are too high for the type of filament you are using. If the filament is melting too quickly, it is harder for the extruder to control the flow rate, which leads to over extrusion and dreaded oozing.</p><h3 dir="ltr">Filament diameter</h3><p dir="ltr">Another contributing factor to over extrusion is filament diameter.[1] For example, if your filament is too narrow for the nozzle in question, the filament will flow through it too quickly. Similarly, if the filament diameter slicer settings are off, it can lead to incorrect flow rates and over extrusion.&nbsp;</p><h3 dir="ltr">Flow rate calibration</h3><p dir="ltr">This leads us to our next cause of over extrusion: incorrect flow rate calibration. Flow rate indicates the amount of filament that is extruded per second and it is determined by a combination of factors, including printing speed, nozzle size, and layer height. You can control the flow rate in slicer programs, usually under “extrusion multiplier” settings. If the flow rate is too high (i.e. too much filament is being pushed through the nozzle) it can lead to over extrusion and poor print quality. Incorrect flow rates can also lead to under extrusion, another common problem in FDM 3D printing.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-fix-under-extrusion-maintenance-and-print-settings" target="_blank">How to fix under extrusion: Maintenance and print settings</a></strong></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 627px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUyNzc1NTg5NDc5LWZpbGFtZW50LmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" width="624" height="459" class="fr-fic fr-dii" alt="Purple Filament Spool"><span class="fr-inner" spellcheck="false">Flow rate controls how much filament is fed through the 3D printer nozzle. If the flow rate is too high, it can cause over extrusion.</span></span></span></p><h2 dir="ltr" id="isPasted">How to fix Over Extrusion</h2><p dir="ltr">If you are encountering over extrusion, the good news is that there are reliable ways to troubleshoot the problem. Let’s take a look:</p><h3 dir="ltr">Calibrate filament diameter&nbsp;</h3><p dir="ltr">If you are seeing the signs of over extrusion in your 3D prints, the first step should be to calibrate your 3D printer flow rate with an accurate filament diameter. There are a few standard filament sizes available on the market: 1.75mm, 2.85 mm, and 3 mm. First, make sure that your print settings are set to the right filament size so that the default flow rate will be in a more accurate range. If you are still having flow rate problems, you may have to manually check the filament diameter.&nbsp;</p><p dir="ltr">Even though most filament suppliers specify the filament diameter, there can be discrepancies in the filament’s actual measurements. By using digital calipers, you can measure the diameter of a length of filament at various points (jot down at least five values along about 20 inches of filament). From there, calculate the average measurement and input it into your slicer settings under machine parameters or filament settings. For instance, while you might be using a 1.75 mm filament, the average diameter might be closer to 1.74 mm. Having an accurate filament size can make for a more accurate default flow setting.&nbsp;</p><h3 dir="ltr">Adjust extrusion multiplier settings</h3><p dir="ltr">If extrusion issues persist after resetting your filament diameter settings, it might be a matter of tweaking your printer’s extrusion multiplier value. Extrusion multiplier settings control the flow rate for filament. Typically, the default extrusion multiplier value is set at 100%. Because over extrusion is a consequence of a high flow rate, you can try lowering the value by increments of between 2.5% and 5%.&nbsp;</p><p dir="ltr">This process might require a little bit of trial and error. In each test print, you’ll be looking for improved dimensional accuracy and print quality. You can also measure your filament to determine how much you need to adjust the extrusion multiplier settings. In one tutorial, Frank’s 3D Shop suggests measuring 120 mm along the filament from the top of the extruder. Mark the filament at the 120 mm line. Next, program the 3D printer to extrude 100 mm of filament. When that’s done, remeasure the filament from the top of the extruder to the marked line. If the 3D printer extruded 104 mm, you should lower the flow rate by 4%. [2]</p><p dir="ltr">It can also be helpful to use your calipers to measure features of your test prints—such as wall thickness—to determine how accurate your prints are. For example, if your wall thickness is set to 1 mm and the calipers report 1.5 mm, try lowering the extrusion multiplier value again. In its slicer software, Simplify3D suggests using an extrusion multiplier value of about 0.9 (90%) for PLA and a value nearer to 1.0 (100%) for ABS.[3] In Cura, the extrusion multiplier settings can be found under “Flow” parameters.&nbsp;</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 627px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUyNzc1NjcxMTQ0LTNkX3ByaW50X2RpbWVuc2lvbnMuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" width="624" height="459" class="fr-fic fr-dii" alt="Caliper measuring 3D printed part"><span class="fr-inner" spellcheck="false">You can use calipers to measure the diameter of filament as well as the accuracy of printed parts.</span></span></span></p><h3 dir="ltr" id="isPasted">Lower the print temperature</h3><p dir="ltr">Finding the right print temperature in FDM 3D printing is critical for many reasons, but the “right” temperature varies from filament to filament. For example, PLA filament prints at a much lower temperature than ABS filament. If you’re dealing with the over extrusion problem and it hasn’t been fixed by flow rate calibration, it is possible that your printing temperature is set too high.&nbsp;</p><p dir="ltr">An overheated hot end will melt the filament too quickly, which makes it harder for the 3D printer to control the rate of extrusion. To solve this issue, first ensure that the printing temperature corresponds with the type of filament. Printing temperatures for <a href="https://www.wevolver.com/article/pla-bed-temperature-print-temperature-settings" target="_blank">PLA</a> should be in the range of 190°C and 220°C, while <a href="https://www.wevolver.com/article/abs-print-temperature-considerations-nozzle-bed-enclosure" target="_blank">ABS</a> prints within the range of 230°C and 260°C, and <a href="https://www.wevolver.com/article/petg-temperature-considerations-nozzle-temperature-heated-bed-cooling" target="_blank">PETG</a> prints within the range of about 210°C and 250°C‎. From there, simply reduce the printing temperature by intervals of no more than 5°C in the 3D printer menu. This should slow the rate of melting and help solve over extrusion. Be careful not to lower the printing temperature too much though, as that can lead to under extrusion.</p><h2 dir="ltr">Preventing Over Extrusion</h2><p dir="ltr">Once you’ve fixed over extrusion, the next step is to prevent it from happening in the future. This&nbsp;involves a combination of regular 3D printer maintenance, proper printer setup, and the use of good-quality filaments. By taking these proactive measures, you can ensure that your 3D prints are consistently of high quality and free from over extrusion issues.</p><h3 dir="ltr">Regular maintenance</h3><p dir="ltr">Regular maintenance of your 3D printer is key to preventing over extrusion. This includes cleaning the extruder nozzle, checking the extruder gear for wear and tear, and ensuring that the printer's belts and pulleys are properly tensioned and aligned. By performing regular maintenance, you can identify and address potential issues before they lead to over extrusion.</p><h3 dir="ltr">Proper printer setup</h3><p dir="ltr">Properly setting up your 3D printer is another step in preventing over extrusion. This involves accurately inputting the filament diameter, setting the correct extrusion multiplier, and optimizing slicer settings such as layer height, print speed, and infill density before printing. By ensuring that your printer is set up correctly, you can minimize the risk of over extrusion and failed prints, which saves both time and material costs.</p><h3 dir="ltr">Good quality filaments&nbsp;</h3><p dir="ltr">Using quality filaments can also help prevent over extrusion. High-quality filaments typically have more consistent diameters and material properties, which can reduce the likelihood of over extrusion. Additionally, using a high-quality extruder and hotend can ensure that the filament is extruded consistently and accurately, further reducing the risk of over extrusion.</p><p dir="ltr">By implementing these preventive measures, you can minimize the occurrence of over extrusion in your future prints, resulting in higher quality and more reliable 3D printed objects.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://s3-us-west-1.amazonaws.com/wevolver-project-images/froala%2F1704902325232-filament.jpg" style="width: 300px;" class="fr-fic fr-dib" alt="Filament feeding into 3D printer"><span class="fr-inner">The quality of filament can influence the success of a print job.</span></span></span></p><h2 dir="ltr">Conclusion</h2><p dir="ltr">Now that you have the fundamentals to deal with over extrusion, it shouldn’t be a problem if it happens to you. By checking your filament settings (including filament type and diameter), print temperature, and flow rate settings, you can stop over extrusion in its tracks and ensure that your prints are of the highest quality. Other factors like printing speed and layer height can also influence the quality and accuracy of your prints. As a general rule, lower print speeds and smaller layer heights result in higher resolution prints. To prevent over extrusion from happening in the future, it’s essential to conduct regular 3D printer maintenance, use the correct print settings, and to use good quality filament.&nbsp;</p><p dir="ltr">If you’ve tried all these fixes for over extrusion but are still suffering from issues such as <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank">stringing</a>, it could be due to other issues, like retraction settings or wet filament. We can help you through that too.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank">3D Printer Stringing: How To Fix It</a></strong></p><h2 dir="ltr">Frequently Asked Questions (FAQs)</h2><h3 dir="ltr">Q: What is over extrusion in 3D printing?</h3><p dir="ltr">A: Over extrusion in 3D printing occurs when the printer extrudes more filament than necessary. This can lead to prints that lack detail and are affected by drooping and stringing. Over extrusion can be caused by a variety of factors, including incorrect temperature settings, improper filament diameter, and incorrect extrusion multiplier settings.</p><h3 dir="ltr">Q: What are the signs of over extrusion?</h3><p dir="ltr">A: Signs of over extrusion include oozing, stringing, as well as prints that are droopy, uneven, and lack detail. You may also notice excess filament on the print bed or around the nozzle.&nbsp;</p><h3 dir="ltr">Q: How do I fix over extrusion?</h3><p dir="ltr">A: Fixing over extrusion involves adjusting the filament diameter, correcting the extrusion multiplier, and optimizing slicer settings. If over extrusion continues to occur after these adjustments, it may be necessary to replace the hotend.</p><h3 dir="ltr">Q: How can I prevent over extrusion?</h3><p dir="ltr">A: Preventing over extrusion involves a combination of proper printer setup and the use of high-quality filaments. Proper printer setup involves accurately inputting the filament diameter, setting the correct extrusion multiplier, and optimizing slicer settings. Using quality filaments can also help prevent over extrusion due to more consistent diameters.</p><h2 dir="ltr">References</h2><p dir="ltr">[1] Cardona C, Curdes AH, Isaacs AJ. Effects of filament diameter tolerances in fused filament fabrication. IU Journal of Undergraduate Research. 2016 May 31;2(1):44-7. Available from: <a href="https://doi.org/10.14434/iujur.v2i1.20917" target="_blank">https://doi.org/10.14434/iujur.v2i1.20917</a>&nbsp;</p><p dir="ltr">[2] Frank’s 3D Shop, October 17, 2017. “Extrusion Problems” [Internet] Available from: <a href="https://www.youtube.com/watch?v=lvTiOxRwEtc" target="_blank">https://www.youtube.com/watch?v=lvTiOxRwEtc</a></p><p dir="ltr">[3] Simplify3D, 2022. “Under-Extrusion” [Internet] Available from: <a href="https://www.simplify3d.com/support/print-quality-troubleshooting/under-extrusion/" target="_blank">https://www.simplify3d.com/support/print-quality-troubleshooting/under-extrusion/</a>&nbsp;</p>

Some of the symptoms of over extrusion are oozing layers, blobs, and stringing

Selecting the right filament settings, print temperature, and flow rate can help solve the common problem of over extrusion in FDM 3D printing.

Dealing with Over Extrusion in 3D Printing

<p dir="ltr" id="isPasted">During FDM 3D printing, the printer extrudes filament and deposits molten material in a sequence of shapes. The printhead is always either depositing material — to lay down a section of the print — or holding back material in order to move from one area to another.</p><p dir="ltr">In practice, however, the printhead isn’t always capable of holding back material. Because the nozzle of a printer contains an open aperture — it doesn’t “close up” in between extrusions — it is susceptible to an issue known as <strong>oozing</strong>. This is when small amounts of material accidentally leak out from the nozzle and onto the build area, negatively affecting print quality.</p><p dir="ltr">Oozing can then lead to a related issue known as 3D printer <strong>stringing</strong>. 3D printer stringing occurs when an oozing printhead has to make lots of travel movements, skipping from one area of the build to another. When the oozing printhead travels a lot, the oozed material forms itself into many fine strands, creating what looks like cobwebs or whiskers over the surface of the printed parts. High-temperature materials like <a href="https://www.wevolver.com/article/petg-print-settings-adjusting-temperature-speed-retraction-to-improve-printing" target="_blank">PETG</a> are especially susceptible to 3D printer stringing, but different filaments like PLA and ABS can also experience it.</p><p dir="ltr">This article looks at the most effective ways to stop 3D printer stringing. It covers simple preventative maintenance steps, as well as the best <a href="https://www.wevolver.com/article/best-ender-3-pro-cura-settings-temperature-speed-retraction-more" target="_blank" rel="noopener noreferrer">slicer settings</a>.</p><h2 dir="ltr">Material Considerations for Preventing Stringing</h2><h3>Filament Selection</h3><p dir="ltr" id="isPasted">Different 3D printing materials have varying properties that can influence their propensity for 3D printer stringing. The quality of the filament can also impact stringing, with low-quality filaments potentially contributing to the issue due to inconsistent diameters, impurities, or poor adhesion properties.</p><p dir="ltr">When choosing a filament, consider its properties and how they may affect stringing. For example, materials like PETG and TPU are more prone to stringing due to their higher viscosity and flexibility compared to PLA or ABS.</p><h3 dir="ltr">Filament Drying</h3><p dir="ltr">One way to prevent 3D printer stringing is to ensure the printing material is in good condition. Filament that has absorbed too much moisture can cause numerous problems, including <a href="https://www.wevolver.com/article/how-to-fix-under-extrusion-maintenance-and-print-settings" target="_blank">under-extrusion</a>, blobs, nozzle jams, weak parts, and stringing.[1]</p><p dir="ltr">Wet filament can cause stringing because the extra moisture absorbed by the material ends up evaporating within the printer nozzle, causing a buildup of pressure that forces out the molten plastic in unwanted places.</p><p dir="ltr">To prevent this issue, filament should be stored in a sealed container with a desiccant. It can also be dried out with a dedicated filament dryer, a food dehydrator, or an oven.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-dry-filament" target="_blank"><em>How to dry filament</em></a></strong></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUxMTQyMzU1MDAzLURlc2ljY2FudF9zaWxpY2FfZ2VsLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" style="width: 300px;" class="fr-fic fr-dib" alt="Desiccant"><span class="fr-inner">Keeping filament dry can prevent stringing</span></span></span></p><h2 dir="ltr">Slicer Settings to Reduce Stringing</h2><h3 dir="ltr">Retraction Settings</h3><p dir="ltr">Printer maintenance is one way of troubleshooting 3D printer stringing, but another common problem that leads to stringing is incorrect slicer settings. These settings can be easily adjusted in slicing software like Cura or Simplify3D.</p><p dir="ltr">Adjusting retraction settings is one way to fix stringing during the FDM printing process.[2] Retraction is when the nozzle pulls back a small amount of filament before it travels (moves to another part of the build area without actively depositing material). By pulling the filament deeper inside the nozzle, the melted plastic is less likely to seep out. A common test print known as a stringing tower is one way to test out the effect of retraction settings.</p><p dir="ltr">To prevent stringing, try adjusting the following retraction settings:</p><ul><li dir="ltr"><p dir="ltr"><strong>Retraction distance</strong>: In increments of 1 mm, increase the amount of filament retracted into the nozzle</p></li><li dir="ltr"><p dir="ltr"><strong>Retraction speed</strong>: In increment of 5 mm/s, increase the speed at which the nozzle retracts the filament</p></li><li dir="ltr"><p dir="ltr"><strong>Minimum travel distance</strong>: In increments of 1 mm, decrease the minimum travel distance required to enable retraction</p></li><li dir="ltr"><p dir="ltr"><strong>Vertical lift</strong>: This retraction setting, called "Z-Hop" in Cura slicer, instructs the printhead to move vertically during travel to avoid dragging along the surface of the part. Disabling this setting can reduce stringing.</p></li></ul><p><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUxMTQyNDA4MjQ1LWhvdGVuZF9ub3p6bGUuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 300px;" class="fr-fic fr-dib" alt="Printer nozzle"><span class="fr-inner">Some stringing issues can be solved via retraction</span></span></span></p><h3 dir="ltr">Print Temperature</h3><p dir="ltr">Runny filament is more likely to ooze out of the 3D printer nozzle than viscous filament, so using a lower temperature in the hotend (and melting the filament slightly less) is one way to tackle 3D printer stringing.[3]</p><p dir="ltr">Of course, using a low temperature can lead to problems of its own, particularly under-extrusion, so it is important to attain a balance between good material flow and prevention of stringing. Try reducing the print temperature in increments of 5 °C in order to find the right temperature.</p><p dir="ltr"><strong>Temperature Towers</strong></p><p id="isPasted">Using a temperature tower — a 3D printable model designed to be printed at increasing or decreasing temperatures along the Z-axis in order to indicate the ideal printing temperature — is a practical method for reducing 3D print stringing.</p><p>While you can design your own tower, there are plenty of downloadable models available for <a href="https://www.thingiverse.com/thing:2493504" target="_blank" rel="noopener noreferrer">download</a> that come with <a href="https://www.wevolver.com/article/your-guide-to-3d-printing-g-code" target="_blank" rel="noopener noreferrer">g-code</a> for instructing the printer to gradually adjust the printing temperature while it prints.&nbsp;</p><p>After the print is finished, carefully examine the temperature tower. Each section represents the filament's behavior at different temperatures, showcasing various levels of stringing and print quality. During your examination, identify the segment of the temperature tower where stringing is minimal and print quality is optimal. Adjust your 3D printer's nozzle temperature to match this value.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/petg-temperature-considerations-nozzle-temperature-heated-bed-cooling" target="_blank"><em>PETG temperature considerations: Nozzle temperature, heated bed &amp; cooling</em></a></strong></p><h3 dir="ltr">Print Speed</h3><p dir="ltr">Adjusting printer speed settings is another way to prevent 3D printer stringing. The two key parameters here are print speed, which determines the speed at which the printhead moves while it deposits material, and travel speed, the speed at which the printhead moves over empty space while it is not depositing any material.</p><p dir="ltr">Print speed does not have a huge impact on stringing. However, it is a parameter closely tied to print temperature: higher print speeds require higher temperatures in order to melt the material quickly enough. Since you may have already reduced your print temperature to prevent stringing, your maximum print speed may be reduced.</p><p dir="ltr">A more relevant speed setting is travel speed. Slow travel speeds can cause stringing, because a slow-moving printhead has more time to dangle an oozing nozzle over the parts below. By increasing travel speed, the nozzle has less time moving through open space and fewer opportunities to drip excess material onto the printed parts.</p><h3 dir="ltr">Wipe Distance</h3><p dir="ltr">To minimize stringing in 3D prints, adjusting the wipe distance is another option. In Cura, you can modify this through the Outer Wall Wipe Distance parameter.</p><p dir="ltr">Typically used to conceal seams, the wipe distance setting also aids in reducing stringing. Wipe distance signifies how far the nozzle moves at a layer's end without extruding material. By setting it to 0.4 mm or higher, excess material is wiped off the wall, preventing oozing and stringing.</p><h3 dir="ltr" id="isPasted">Combing</h3><p dir="ltr">Combing mode can help reduce stringing in 3D prints. This setting, available in some slicers, alters the path of the print head during non-printing moves to minimize the need for retractions. Instead of retracting the filament and moving directly between two points, the print head follows the contours of the printed object, avoiding crossing over empty spaces where possible.</p><p dir="ltr">By keeping the print head within the boundaries of the printed object, combing mode reduces the likelihood of oozing and stringing during non-printing moves. To enable and configure combing mode, consult your slicer software's documentation or settings menu. Some slicers offer different combing modes, such as "All," "No Skin," or "Within Infill," which provide varying levels of combing based on the specific needs of your print.</p><h2 dir="ltr">Other Ways to Reduce Stringing</h2><h3 dir="ltr" id="isPasted">Nozzle Maintenance</h3><p dir="ltr">Another common cause of 3D printer stringing is a clogged nozzle. Material passing through the FDM printer nozzle can occasionally get stuck or leave residue, and this residue must be regularly removed to ensure smooth operation of the hotend.</p><p dir="ltr">There are several ways to unclog a nozzle. Suitable tools include a brass wire brush, a needle, a heat gun, or a dedicated cleaning filament. ABS residue can also be removed by immersing the nozzle in acetone.</p><h3 dir="ltr">Post-Processing</h3><p><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjk2OTI3NzYwMjkyLWhlYXRfZ3VuLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" style="width: 300px;" class="fr-fic fr-dib" alt="heat gun"><span class="fr-inner">Using a heat gun is a fast way to remove plastic residue caused by stringing</span></span></span></p><p dir="ltr">Post-processing techniques such as sanding, polishing, and chemical smoothing can be used to remove the plastic residue left by stringing.</p><p dir="ltr"><strong>Manual Stringing Removal</strong></p><p dir="ltr">The plastic residue stuck on the surface of a print can often be removed manually with a knife or pliers. Small bits of material that cannot be removed in this way can be removed later with a more precise method.</p><p dir="ltr"><strong>Sanding</strong></p><p dir="ltr">Using sandpaper is another way to remove stringing residue, especially small protrusions that cannot easily be removed using a knife or pliers. Apply polish after sanding to achieve a smooth finish.</p><p dir="ltr"><strong>Hairdryer</strong></p><p dir="ltr">Using a heat gun or a simple hairdryer is a fast and simple way to remove thin webs of plastic residue. Often, the heat will cause the strings to ball up, allowing them to be easily removed.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/3d-print-post-processing-steps-supports-sanding-smoothing-more" target="_blank" rel="noopener noreferrer"><em>3D print post-processing steps: supports, sanding, smoothing, more</em></a></strong></p><h2 dir="ltr">Key Takeaways</h2><p dir="ltr">Like many common 3D printer problems, stringing can be prevented with a combination of proper 3D printer maintenance and fine-tuning of slicer settings.</p><p dir="ltr">If you are struggling to identify the root cause of your 3D printer stringing, it is probably worth carrying out the physical maintenance — correctly storing filament and regularly cleaning the printer nozzle — before adjusting any slicer settings. Even if moist filament or a clogged nozzle is <em>not</em> the root cause of the stringing, carrying out these basic preventative measures is a good way to maintain print quality over future prints. Additionally, a slicer’s default settings are precisely optimized for individual print materials and typically do not require radical alteration in order to deliver good results.</p><p dir="ltr">That being said, adjustment of print parameters within the slicing software gives total control over the print process and in many cases is necessary to fix stringing. In particular, retraction and temperature settings are often the key to unlocking successful prints without oozing or stringing issues.</p><p dir="ltr">Finally, it is important to remember that stringing and other surface defects are not always critical and can often be mitigated via post-processing techniques like sanding.</p><h2 dir="ltr" id="isPasted">Frequently Asked Questions</h2><p dir="ltr"><strong>What is 3D printer stringing?&nbsp;</strong></p><p dir="ltr">3D printer stringing is a common issue that occurs when thin strands of filament are left behind between different parts of a printed object, creating an unwanted web-like appearance.</p><p dir="ltr"><strong>How can I prevent stringing in my 3D prints?&nbsp;</strong></p><p dir="ltr">Preventing stringing involves adjusting print settings such as retraction, temperature, and print speed, as well as using high-quality filament, maintaining your printer, and storing filament properly.</p><p dir="ltr"><strong>What is the role of retraction in preventing stringing?&nbsp;</strong></p><p dir="ltr">Retraction is the process of pulling the filament back slightly during non-printing moves to prevent oozing, which can cause stringing. Adjusting retraction settings can help reduce or eliminate stringing.</p><p dir="ltr"><strong>How does printing temperature affect stringing?&nbsp;</strong></p><p dir="ltr">High printing temperatures can cause the filament to become more fluid, increasing the likelihood of oozing and stringing. Optimizing the printing temperature for your specific filament material can help reduce stringing.</p><h2 dir="ltr">References</h2><p dir="ltr">[1] Kwon S, Lee S, Kim Y, Oh Y, Lee S, Kim J, Kwon J. <a href="https://www.hindawi.com/journals/js/2020/8846466/" target="_blank" rel="noopener noreferrer">A Filament supply system capable of remote monitoring and automatic humidity control for 3D printer</a>. Journal of Sensors. 2020 Jun 24;2020.</p><p dir="ltr">[2] <a href="https://support.ultimaker.com/hc/en-us/articles/360012016280-How-to-fix-stringing" target="_blank" rel="noopener noreferrer">How to fix stringing</a> [Internet]. Ultimaker Support. [cited 2022 Apr 25].</p><p dir="ltr">[3] Paraskevoudis K, Karayannis P, Koumoulos EP. <a href="https://www.mdpi.com/2227-9717/8/11/1464" target="_blank" rel="noopener noreferrer">Real-time 3D printing remote defect detection (stringing) with computer vision and artificial intelligence</a>. Processes. 2020 Nov;8(11):1464.</p>

3D printer stringing is a common problem in FDM printing

Prints covered in plastic cobwebs? Like many FDM users, you’re probably the victim of 3D printer stringing. Fortunately, stringing can be prevented via printer maintenance and adjustment of slicer settings.

3D Printer Stringing: How To Fix It

<p dir="ltr" id="isPasted">It is always a disappointment when a finished 3D print comes off the build platform with defects and imperfections. Whether it’s a 3D print that has become unstuck from the print bed and <a href="https://www.wevolver.com/article/what-causes-3d-print-warping-and-how-to-prevent-it" target="_blank">suffered from warping</a>, or a <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank" rel="noopener noreferrer">print with stringing</a> or other surface irregularities: a ruined print amounts to wasted time and material costs. We’ve already addressed <a href="https://www.wevolver.com/article/3d-print-not-sticking-to-print-bed-heres-the-solution" target="_blank">how to fix problems like poor first layer bed adhesion</a>—which can lead to 3D print warping—but in this article we’ll be focusing on another type of defect: 3D print blobs &amp; zits. Keep reading to understand what causes blobs and zits and how to prevent them from happening in the future.</p><h2 dir="ltr">What causes 3D printing blobs and zits?</h2><p dir="ltr">In 3D printing, blobs (also known as zits) are extrusion irregularities that appear on the surface of a 3D printed part. Blobs and zits are distinguished from other surface defects, like <a href="https://www.wevolver.com/article/z-banding-rooting-out-the-cause-and-fixing-the-3d-printing-defect" target="_blank">Z-banding</a>, by their inconsistency. Whereas Z-banding produces a ribbed pattern on the 3D print, blobs are quite literally bits of oozed filament that stick out from the print’s surface.&nbsp;</p><p dir="ltr">3D print blobs &amp; zits are primarily caused by over-extrusion and the motion of the filament extruder. If, for example, you are printing a part with a circular perimeter, blobs can occur when the print head returns to its starting position. The material builds up at this point, which can result in the formation of a filament blob. Similarly, if the 3D printer extruder starts and stops several times over the course of a 3D print job, blobs and zits can also occur.&nbsp;</p><p dir="ltr">Blobs and zits can also be caused by 3D printer nozzle retraction. In the FDM 3D printing process, retraction is a technique in which the hot end briefly pulls filament back instead of extruding it out. This method is used to reduce unwanted material extrusion, like stringing, as the print head moves to a new print location. However, if the retraction settings on your 3D printer are not optimized, the process may actually have a negative effect, causing blobs or zits.</p><p dir="ltr">Other 3D printer settings, such as nozzle temperature, can also increase the risk of blobs. For example, if the nozzle temperature is too high, filament can come oozing out too quickly and create defects on the print surface. Printing speeds can also be a factor if they are too fast and don’t allow for sufficient cooling time between layers. In other words, if new layers are deposited before the underlying layer of filament has had time to adequately solidify, it can be squished and deformed by the weight of the layers above it.</p><p dir="ltr"><strong>Recommended reading:</strong> <a href="https://www.wevolver.com/article/what-causes-3d-print-warping-and-how-to-prevent-it" target="_blank">What Causes 3D Print Warping and How to Prevent It</a></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 692px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwOTQ1OTQzOTE0LTNkX3ByaW50aW5nLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" width="624" height="459" class="fr-fic fr-dii" alt="3D printer nozzle extruding red filament" style="width: 690px;"><span class="fr-inner">If the 3D printer nozzle is too hot it can cause over-extrusion resulting in blobs and zits.</span></span></span></p><h2 dir="ltr">What can you do to prevent 3D printing blobs?&nbsp;</h2><p dir="ltr">Fortunately, there are a number of ways to minimize the risk of blobs and zits in FDM 3D printing. Below are some of the key strategies you can try to prevent the 3D printing defects from occurring.</p><h3 dir="ltr">Adjust Retraction Settings</h3><p dir="ltr">In slicer software, you can adjust retraction settings to control how much filament is pulled back into the nozzle and at what point this happens. Finding the right retraction settings can minimize material buildup either at the beginning of the print head’s path along the part perimeter or as it completes a layer and rejoins its starting position (for this, see coasting settings below).</p><p dir="ltr">In general, it is advisable to use a smaller retraction distance (this is the amount of filament pulled back into the nozzle). This is because if too much filament is retracted, air can also be pulled into the nozzle. When the printhead then goes to extrude filament, the air is heated along with the filament, which can cause extrusion inconsistencies, like blobs and bubbles on the print surface. Too little retraction, however, can lead to over-extrusion and defects like stringing and blobs and zits. It’s all about finding the sweet spot, so you might need to try out a few different retraction distance settings. The amount of retraction will also depend on the type of FDM 3D printer: systems with direct drive extruders only require a retraction distance between 0.5 mm to 2 mm. Bowden extruder systems, on the other hand, can require higher retraction values, as much as 15 mm.[1]</p><p dir="ltr">Retraction speed is also worth mentioning. This setting controls how quickly the filament is pulled back into the nozzle. If the retraction speed is too slow, your print may suffer from oozing filament. A standard range for retraction speed is between 20 mm/second and 100 mm/second.</p><h3 dir="ltr">Activate Coasting Settings</h3><p dir="ltr">Coasting is a setting built in to most 3D printing slicer programs, including Simplify3D and Cura. Coasting is often found under retraction settings and controls if the print head stops extruding filament at the end of each layer perimeter. Coasting is therefore helpful in reducing blobs or zits that are caused by filament buildup when the extruder comes back to its starting point.</p><p dir="ltr">When you activate coasting, the slicing program will essentially tell the 3D printer nozzle when to stop extruding filament—usually this will be triggered a fraction of a millimeter before the printhead completes the part’s perimeter. Coasting therefore anticipates that there will be over-extrusion when the printhead stops extruding and stops the buildup of material at these starting/ending locations. Coasting also helps to relieve pressure inside the nozzle that causes over-extrusion. It is advisable to begin with a smaller coasting distance, such as 0.2 mm, and increase the value incrementally until you no longer see blobs appearing on the part’s surface.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 690px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwOTQ2MDg3MjYxLTNkX3ByaW50dGVyX3NldHRpbmdzLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" width="624" height="448" class="fr-fic fr-dii" alt="3D printer extruding yellow filament"><span class="fr-inner">Coasting and retraction settings can help to minimize blobs and zits if used properly.</span></span></span></p><h3 dir="ltr">Wiping and Shell Settings</h3><p dir="ltr">Another group of <a href="https://www.wevolver.com/article/best-ender-3-pro-cura-settings-temperature-speed-retraction-more" target="_blank" rel="noopener noreferrer">slicer settings</a> that can help minimize blobs and zits are the wipe parameters. With wiping activated, the 3D printer will drag the nozzle at the end of every printed layer along the outer wall of the printed part to remove any material buildup. With this setting, it is common for retraction to happen simultaneously, which can help prevent blobs and zits. A typical wipe distance—the length that the nozzle will wipe along the outer wall—is 0.4 or 0.5 mm. Wiping can also help to reduce the appearance of the z-seam.</p><p dir="ltr">Because 3D print blobs and zits are primarily an aesthetic issue on the outer shell of a part, tuning your 3D printer’s shell parameters can improve the overall print quality by preventing or covering up blobs and zits. For instance, simply activating the “outer before inner wall” setting inf your slicer can improve the quality of the part’s outer shell. This setting tells the 3D printer to extrude the outer layers of a part before printing the inner structure and infill. Not only can this reduce the risk of blobs and blemishes, it can also improve the dimensional accuracy of your print.</p><h3 dir="ltr">Adjust Print Temperature and Speed</h3><p dir="ltr">As we saw, a too-hot print head can lead to over-extrusion, and rapid printing speeds can lead to defects like blobs and zits due to lack of cooling. Therefore, lowering the print temperature and print speed can help to reduce the risk of blobs and zits. The temperature of your nozzle will depend on the type of filament you are 3D printing. For example, PLA filament typically requires a nozzle temperature of between 200-210 °C.[2] If blobs are still occurring in this range, try lowering the nozzle temperature in 5°C increments.</p><p dir="ltr">Reducing the print speed can also reduce the occurrence of blobs and zits. In general, a lower printing speed can improve print quality because the nozzle has more time to deposit the filament and the extruded layer has more time to cool before the next layer is applied. Try reducing your print speed by 5 to 10 mm/s to see if that helps minimize the appearance of blobs.</p><p dir="ltr"><strong>Recommended reading:</strong> <a href="https://www.wevolver.com/article/abs-print-temperature-considerations-nozzle-bed-enclosure" target="_blank">ABS print temperature considerations: Nozzle, bed, enclosure</a></p><h3 dir="ltr">Adjust Fan Settings</h3><p dir="ltr">In addition to finding the right print head temperature, you can also reduce the risk of 3D print blobs and zits by increasing your 3D printer’s fan speeds. (Or, if your 3D printer doesn’t have a built-in fan, it can help to integrate one.) A fan helps to regulate the temperature of the 3D printing environment and can help prevent overheating.&nbsp;</p><p dir="ltr">This, in turn, ensures that the layers of melted thermoplastic that are deposited onto the print bed are cooled and solidified at a controlled rate. Because over-extrusion and squished print layers are two potential causes of blobs and zits, increased cooling in the print chamber using fans can promote better quality prints. Of course, over-cooling your print environment can also impact layer adhesion—it’s all about finding a balance.</p><h2 dir="ltr">Key Takeaways</h2><p dir="ltr">In the end, the first step to preventing 3D printing defects like blobs and zits is to understand where they come from. Factors like temperature and slicer settings can be the cause and solution to blobs and zits. So if you’re experiencing imperfections in your 3D print’s outer shell, be sure to play with your retraction, coasting, and wipe settings, as well as adjust your nozzle print temperature. It may take some time to find the right combination of settings for a given material, so start out with a small test print. The results will be worth it!&nbsp;</p><h2 dir="ltr">References</h2><p dir="ltr">[1] Simplify3D, 2022. “Stringing or Oozing.” [Internet] <a href="https://www.simplify3d.com/support/print-quality-troubleshooting/stringing-or-oozing/" target="_blank">https://www.simplify3d.com/support/print-quality-troubleshooting/stringing-or-oozing/</a> [Accessed April 20, 2022].</p><p dir="ltr">[2] Ultimaker, May 28, 2021. “How to Print with Ultimaker PLA.” [Internet] <a href="https://support.ultimaker.com/hc/en-us/articles/360011952740-How-to-print-with-Ultimaker-PLA" target="_blank">https://support.ultimaker.com/hc/en-us/articles/360011952740-How-to-print-with-Ultimaker-PLA</a> [Accessed April 21, 2022]</p>

Prevent 3D print blobs and zits by adjusting temperature and slicer settings.

Surface imperfections on a 3D print can be frustrating but they’re not insurmountable. Here is how to prevent and fix 3D print blobs and zits by adjusting 3D printer and slicer settings.

How to Prevent 3D Print Blobs & Zits

<p dir="ltr">When an FDM 3D printer works properly, it extrudes thermoplastic filament and deposits it in a sequence of two-dimensional layers. Sometimes, however, the 3D printer is unable to extrude the right amount of material, leading to noticeable issues like thin layers, missing layers, gaps, holes, and weakness of the printed part.</p><p dir="ltr">The problem of a 3D printer failing to supply adequate material is called under extrusion, and it happens to all printer users from time to time. Generally, under-extrusion is not a sign of any major hardware problem with the 3D printer, but the phenomenon can have a range of causes, which makes it tricky to diagnose the underlying issue. Under-extrusion can usually be solved by printer maintenance — cleaning the nozzle, for instance — or by adjustment of print settings.</p><p dir="ltr">This article examines what can cause under-extrusion and offers solutions for how to fix under-extrusion problems, both through physical maintenance of the 3D printer and adjustment of print parameters.</p><h1 dir="ltr" id="isPasted">Under-Extrusion or Over-Extrusion?</h1><p id="isPasted">In 3D printing, both over-extrusion and under-extrusion are problems related to the amount of filament extruded by the printer, but they manifest in different ways, affecting the print quality and structural integrity of the object being printed.</p><p>Under-extrusion occurs when the 3D printer doesn't supply enough filament to create the intended layers of the object. This can result in gaps, weak structures, and a rough surface finish. Under-extrusion can happen due to various factors such as a partially clogged nozzle, improper slicing settings, insufficient filament tension, or a worn-out drive gear. It's akin to a pen running out of ink while drawing; the printer doesn't have enough material to complete the designated paths, leading to incomplete prints with visible defects.</p><p>Over-extrusion, on the other hand, happens when the printer supplies more filament than necessary for the specified print. This excess material can cause issues like blobbing, <a href="https://www.wevolver.com/article/3d-printer-stringing-how-to-fix-it" target="_blank" rel="noopener noreferrer">stringing</a> between printed parts, and a loss of fine details. Over-extrusion often occurs due to incorrect <a href="https://www.wevolver.com/article/best-ender-3-pro-cura-settings-temperature-speed-retraction-more" target="_blank" rel="noopener noreferrer">slicer settings</a>, where the printer is instructed to extrude more material than required. It can also be caused by a misaligned printer, incorrect nozzle diameter settings, or a too-high printing temperature. Over-extrusion is comparable to using a pen that leaks blotches of ink.</p><p><strong>Recommended reading: <a href="https://www.wevolver.com/article/dealing-with-over-extrusion-in-3d-printing" target="_blank" rel="noopener noreferrer"><em>Dealing with Over Extrusion in 3D Printing</em></a></strong></p><h1 dir="ltr">Fixing Under-Extrusion with Printer Maintenance</h1><p dir="ltr">There are several potential causes of under-extrusion, and many of these relate to the condition and cleanliness of the 3D printer. Clogs, dirtiness, and incorrect calibration can all lead to extrusion problems, so learning how to identify these basic issues is an easy way to prevent under-extrusion.</p><h2 dir="ltr">Nozzle&nbsp;</h2><p dir="ltr">FDM printers must feed a spool of thermoplastic filament through various parts of the machine, and there are a few areas where the material can leave a buildup of residue and cause clogging.</p><p dir="ltr">If under-extrusion starts happening suddenly (and you haven’t made any changes to the print setup) then a clogged nozzle is a likely culprit. There are few ways to clean and remove blockages from a 3D printer nozzle, including:</p><ul><li dir="ltr"><p dir="ltr">Using a brass wire brush (not steel) to remove debris</p></li><li dir="ltr"><p dir="ltr">Using a needle to remove internal debris</p></li><li dir="ltr"><p dir="ltr">Running a special cleaning filament through the printer and performing a cold pull (letting the filament cool while it is in the nozzle, then pulling it out)[1]</p></li><li dir="ltr"><p dir="ltr">Removing the nozzle and immersing it in a chemical such as acetone (best for ABS)</p></li><li dir="ltr"><p dir="ltr">Removing the nozzle and using a heat gun to melt any filament left inside</p></li></ul><p dir="ltr">Another hot end issue that can cause under-extrusion is a worn-out PTFE coupler — a component found on common FDM machines like the Creality Ender 3 and Ultimaker 2. The coupler should be replaced if it becomes deformed by heat.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwNTIwNzQzNjEzLW5venpsZS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" style="width: 300px;" class="fr-fic fr-dib" alt="Clogged nozzle"><span class="fr-inner">Clogged nozzles can cause under-extrusion</span></span></span></p><h2 dir="ltr">Bowden tube</h2><p dir="ltr">The hot end isn’t the only place where clogs can occur. Bowden tubes can also get clogged up with filament, and this can equally cause under-extrusion, as not enough filament is able to pass through.</p><p dir="ltr">A clogged Bowden tube is often the result of heat creep: when the tube gets hotter than it’s supposed to be and melts the filament before it reaches the hot end. To clean the tube, first remove it, then push a small piece of sponge or cloth through it using a piece of filament.</p><h2 dir="ltr">Drive gears and motor</h2><p id="isPasted">Drive gears are responsible for gripping the filament and pushing it into the hot end where it melts and forms the print layers. Over time, these gears can accumulate debris, such as dust or leftover filament particles, causing the grip on the filament to weaken. Regular cleaning and inspection of the drive gear can prevent this. Additionally, the gear's teeth might wear out, reducing their effectiveness. Replacing worn-out gears ensures a proper grip on the filament, enhancing the extrusion process.</p><p dir="ltr">One reason why debris might accumulate in the extruder gears is incorrect tension on the filament. The tension must be great enough to cause small marks in the filament but not so great that the gears strip chunks out of the material, resulting in thin and weak layers.</p><h2 dir="ltr">Cooling fan</h2><p dir="ltr">Bowden tubes can get clogged when filament melts too early on its journey to the nozzle. This is sometimes caused by issues with the printer’s cooling apparatus: if the fan is not able to regulate temperature, the material can overheat, leading to under-extrusion. The cooling fan may cease to function properly if it is installed improperly or if jamming has occurred. Check it for stray pieces of filament or other debris, and remove these items with a brush.</p><h2 dir="ltr">Filament</h2><p dir="ltr">Problems with the 3D printing material can cause under-extrusion. These problems can include damp filament, knots in the filament, and incorrect material settings (discussed in the print settings section).</p><p dir="ltr">Damp filament can indirectly cause under-extrusion. This is because filament expands when it absorbs too much moisture, and a bloated strand of filament can cause clogging within the nozzle. Fortunately, it is easy to keep filament dry by storing it correctly and, if necessary, drying it out thoroughly before use. The link between moist filament and under-extrusion is particularly noticeable with flexible filaments like TPU.[2]</p><p dir="ltr">Filament can also become tangled or knotted, especially when it is regularly removed from the 3D printer and replaced. Using a filament clip can help to prevent this issue.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-dry-filament" target="_blank"><em>How to dry filament</em></a></strong></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwNTIwNzk1MzY5LWZpbGFtZW50LmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" style="width: 300px;" class="fr-fic fr-dib" alt="Tangled filament"><span class="fr-inner">Tangled filament can lead to under-extrusion</span></span></span></p><h2 dir="ltr">Firmware and software updates</h2><p dir="ltr">Under-extrusion and myriad other issues can be caused by minor technical bugs, which tend to pop up when using outdated 3D printer firmware and slicer software. Install updates when they become available.</p><h1 dir="ltr">Fixing Under-Extrusion with Print Settings</h1><p dir="ltr">Cleaning, maintenance, calibration, and firmware updates can all help to prevent under-extrusion and related issues. Sometimes, however, adjustment of print settings (in slicer software like Cura, for example) is all it takes to fix under-extrusion.</p><h2 dir="ltr">Nozzle temperature</h2><p dir="ltr">A common and easily resolvable cause of under-extrusion is insufficient nozzle temperature. If the hot end does not melt the material enough, it can struggle to push enough of it through the nozzle.</p><p dir="ltr">Slicers usually have default printing profiles for certain filaments. But it may be necessary to adjust the printing temperature by 5 or 10 °C to achieve the best results. Also note that non-brass nozzles such as hardened steel nozzles require higher temperatures, as they do not retain heat well.</p><h2 dir="ltr">Flow rate</h2><p dir="ltr">Flow rate, the amount of plastic extruded per second, can be a cause of under-extrusion. When the set flow rate is higher than the actual capabilities of the printer, parts may come out under-extruded. Flow rate is defined by layer height, nozzle diameter, and printing speed.</p><p dir="ltr">In slicers such as Cura and Simplify3D, flow rate can be most easily adjusted via the extrusion multiplier parameter, which is usually set at around 90% (or 0.9) for PLA and 100% (or 1.0) for ABS.[3] When under-extrusion occurs, this value can be increased in small increments until the problem goes away.&nbsp;</p><p dir="ltr">Note that the default flow rate will be incorrect if the filament diameter has not been set properly. For example, if you are using 2.85 mm filament but the slicer thinks you are using 1.75 mm, the printer will not feed through enough material at once. For the highest level of accuracy, you can use calipers to measure the exact diameter of your material.</p><h2 dir="ltr">First-layer calibration</h2><p><span class="fr-img-caption fr-fic fr-dib" style="width: 302px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjk4MzkwNDQ3ODk1LTNEX3ByaW50ZXIuanBnIiwiZWRpdHMiOnsicmVzaXplIjp7IndpZHRoIjo5NTAsImZpdCI6ImNvdmVyIn19fQ==" style="width: 300px;" class="fr-fic fr-dib" alt="first layer"><span class="fr-inner">Printing the first layer too close to the bed can cause under-extrusion</span></span></span></p><p dir="ltr">Under-extrusion can be caused by printing the first layer too close to the build surface. Users sometimes calibrate the first layer very close to the build surface in order to improve adhesion, but this can have the negative effect of actually obstructing the nozzle and preventing the natural flow of filament [4]</p><p dir="ltr">First-layer calibration should strike a balance between adhesion and flow. If the print does not stick to the print bed, then a change in build surface material or use of an adhesive should be considered instead.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-beds-glass-pei-adhesive" target="_blank"><em>How to clean 3D printer beds: Glass, PEI, adhesive</em></a></strong></p><h2 dir="ltr">Retraction</h2><p dir="ltr">Retraction is when the printer nozzle pulls back a bit of filament before it travels. Retraction can prevent issues like oozing and stringing, but incorrect retraction settings can cause under-extrusion issues.</p><p dir="ltr">When using significant retraction, under-extrusion may occur immediately after travel (when the printhead hops from one part of the print to another without depositing material), as the interruption of material deposition causes a loss of pressure. Under-extrusion may be mitigated by increasing the retraction extra prime amount, which increases pressure in the nozzle after retraction.</p><h1 dir="ltr">Troubleshooting Under-Extrusion Checklist</h1><p dir="ltr">Although under-extrusion is difficult to stamp out altogether, carrying out regular maintenance can help to prevent the issue in most cases. And even if the problem turns out to be a slicer-related issue rather than a hardware issue, it never hurts to clean your nozzle and other hardware components anyway.</p><p dir="ltr">If under-extrusion occurs, attempt the following:</p><ul><li dir="ltr"><p dir="ltr">Check nozzle and Bowden tube for clogs</p></li><li dir="ltr"><p dir="ltr">Clean gears, motor, and cooling fan</p></li><li dir="ltr"><p dir="ltr">Store filament in a secure, dry place and check the spool for knots and overlap</p></li><li dir="ltr"><p dir="ltr">Update printer firmware</p></li><li dir="ltr"><p dir="ltr">Try increasing nozzle temperature</p></li><li dir="ltr"><p dir="ltr">Try increasing flow rate</p></li><li dir="ltr"><p dir="ltr">Try printing first layer further from print surface</p></li><li dir="ltr"><p dir="ltr">Try adjusting retraction settings</p></li></ul><h1 dir="ltr" id="isPasted">Conclusion</h1><p dir="ltr">In summary, resolving under-extrusion issues in 3D printing demands a multi-faceted approach. Regular nozzle maintenance, involving clearing clogs and debris, ensures a consistent filament flow. Proper filament drying, especially for moisture-sensitive materials, preserves filament integrity and prevents irregular extrusion. And adjusting settings like printing temperature according to the filament type can prevent overheating and nozzle jams. By performing the necessary maintenance and adjustments, enthusiasts and professionals can significantly enhance the quality of their prints.</p><h1 dir="ltr" id="isPasted">Frequently Asked Questions</h1><p id="isPasted"><strong>What is under-extrusion?</strong></p><p>Under-extrusion is a 3D printing issue where the printer doesn't supply enough filament, resulting in incomplete layers, weak structures, and rough surface finishes in printed objects.</p><p><strong>How can I diagnose under-extrusion?</strong></p><p>Diagnosing under-extrusion involves examining the print for gaps between lines, inconsistent layer adhesion, or a visibly weak structure. It often manifests as visible spaces or irregular patterns in the printed layers.</p><p><strong>How does flow rate affect under-extrusion?</strong></p><p>Flow rate, which determines the amount of filament extruded per second, directly influences under-extrusion. If the flow rate is too low, insufficient filament is supplied, leading to under-extruded prints; if it's too high, it can cause over-extrusion issues.</p><p><strong>Why does wet filament cause under-extrusion?</strong></p><p>Wet filament absorbs moisture from the air, leading to its physical properties changing. When this filament is extruded, the moisture turns into steam, causing irregular flow and nozzle blockages, resulting in under-extrusion during printing.</p><h1 dir="ltr">References</h1><p dir="ltr">[1] <a href="https://support.ultimaker.com/hc/en-us/articles/360011620800-How-to-perform-a-hot-and-cold-pull" target="_blank" rel="noopener noreferrer">How to perform a hot and cold pull</a> [Internet]. Ultimaker. 2020 [cited 2022 Apr 19].</p><p dir="ltr">[2] Bruère VM, Lion A, Holtmannspoetter J, Johlitz M. <a href="https://link.springer.com/article/10.1007/s40964-022-00300-y" target="_blank" rel="noopener noreferrer">Under-extrusion challenges for elastic filaments: The influence of moisture on additive manufacturing</a>. Progress in Additive Manufacturing. 2022 Jun;7(3):445-52.</p><p dir="ltr">[3] <a href="https://www.simplify3d.com/support/print-quality-troubleshooting/under-extrusion/" target="_blank" rel="noopener noreferrer">Under-Extrusion</a> [Internet]. Simplify3D. 2019 [cited 2022 Apr 19].</p><p dir="ltr">[4] <a href="https://help.prusa3d.com/en/article/under-extrusion_2007/" target="_blank" rel="noopener noreferrer">Under-extrusion</a> [Internet]. Prusa Knowledge Base. 2021 [cited 2022 Apr 19].</p>

Under-extrusion can be fixed with maintenance and optimized print settings

One of the most common issues with FDM 3D printing is under-extrusion, which manifests itself as thin or missing layers or visible holes in the structure of the part.

How to Fix Under Extrusion: Maintenance and Print Settings

<p dir="ltr" id="isPasted">First-layer adhesion is critical to ensuring that your 3D print will be a success. But achieving good bed adhesion can be easier said than done. Corners unstick from the 3D printer’s build surface, <a href="https://www.wevolver.com/article/what-causes-3d-print-warping-and-how-to-prevent-it" target="_blank">warping occurs</a>, and ultimately parts fail. Moreover, adhesion problems can be caused by a number of factors or any combination of issues, including bed leveling, bed temperature, extruder temperature, build plate deficiencies, <a href="https://www.wevolver.com/article/best-ender-3-pro-cura-settings-temperature-speed-retraction-more" target="_blank" rel="noopener noreferrer">slicer settings</a>, and more. Fortunately, there are several steps you can take to resolve the problem of a 3D print not sticking to print bed. In this article, we’re looking at the importance of bed adhesion when 3D printing as well as several different methods you can use to improve adhesion and, ultimately, print results.</p><h2 dir="ltr">The Importance of Bed Adhesion</h2><p dir="ltr">Bed adhesion plays a crucial role in the success of a 3D print. When the first layer of a print adheres well to the bed, it provides a solid foundation for the rest of the print. This foundation is essential for ensuring a print's structural integrity and dimensional accuracy as well as minimizing the risk of defects.</p><p dir="ltr">If good bed adhesion is not achieved, it can lead to a variety of issues, such as warping, curling, or part detachment of the print from the bed. In some cases, poor adhesion can even damage the printer itself, as detached prints may collide with the nozzle or other components. By understanding what factors influence bed adhesion, you can significantly improve the success rate of your 3D prints and minimize the risk of print failures due to poor bed adhesion.</p><h2 dir="ltr">Method #1: Level the Bed</h2><p dir="ltr">One of the main reasons a 3D print may not stick to the print bed is poor bed leveling. If one side of your printer bed is even marginally higher or lower than the other side, it will affect the quality of your 3D print and how well the first layers of the print adhere to the build surface. In short, this is because the nozzle will be further away from part of the print bed and filament won’t be deposited evenly. When the nozzle is too close, it can cause the filament to be squished and spread out, resulting in thin layers and poor adhesion. Conversely, when the nozzle is too far away, the filament may not make sufficient contact with the bed, leading to weak adhesion.</p><p dir="ltr">Ensuring your 3D printed bed is level can solve adhesion problems. Depending on the 3D printer hardware you have, you might be able to level the bed automatically or you may have to do it manually. If you are adjusting the bed level manually, one of the most popular methods for leveling a print bed is to use a piece of paper.&nbsp;</p><p dir="ltr">Simply bring your 3D printer nozzle very close to the print surface and place a sheet of paper in between the nozzle and the build plate. Gradually raise the corner of the print bed using your machine’s leveling knobs until there is a bit of resistance when pulling the paper out. Repeat this on all corners of the print bed. You can also print a test <a href="https://www.wevolver.com/article/3d-printing-rafts-vs-brims-vs-skirts-how-to-get-started" target="_blank" rel="noopener noreferrer">skirt</a> after using the paper method to check the evenness of the first print layers. This is also a good idea because it allows you to check the level of the print bed while the machine is hot.</p><h2 dir="ltr">Method #2: Change the Z-Offset</h2><p dir="ltr">The distance between the 3D printer nozzle and the build platform, known as the <a href="https://www.wevolver.com/article/z-offset-what-it-is-and-how-to-adjust-it" target="_blank" rel="noopener noreferrer">Z-offset</a>, may also be causing adhesion problems. In other words, if the nozzle is too close to the build surface, the first layer will be squished and won’t be evenly extruded; if it’s too far away, the filament extrusion also won’t stick to the build platform properly. The good news is that you can encourage good adhesion by positioning the 3D printer nozzle at the right distance.</p><p dir="ltr">The z-offset can be adjusted in slicing software by changing the measurement values. Once the value is set, the z-axis will align itself accordingly to the print bed. If you are having adhesion problems, changing the z-offset should be used as a last resort. Where this method is most helpful is in situations where you are working with a thick build plate or if you are printing on a substrate.&nbsp;</p><p dir="ltr">When experimenting with nozzle distance, make small adjustments and observe the results on test prints. Look for signs of proper adhesion, such as a smooth and even first layer, and adjust the nozzle distance accordingly until the desired adhesion is achieved.</p><h2 dir="ltr">Method #3: Clean the Print Bed</h2><p dir="ltr">It is imperative that your print surface be clean before you start 3D printing. If there are any inconsistencies, like leftover glue or filament stuck to the print surface area, it can cause first layer adhesion problems. The <a href="https://www.wevolver.com/article/how-to-clean-3d-printer-beds-glass-pei-adhesive" target="_blank">best cleaning technique for a print bed</a> depends entirely on the build plate material.&nbsp;</p><p dir="ltr">If you are working with a glass print bed that has filament or adhesive residue on it, start by removing the glass bed from the 3D printer and scraping the residue off using a dry scraper. From there, you can wash the plate with soapy water or window cleaner. It is also a good idea to give your glass build plate a final wipe using Isopropyl alcohol (IPA) or acetone. These cleaning products will help to remove any remnants of grease without damaging the glass surface. You can also follow these cleaning steps with a removable borosilicate glass print bed.</p><p dir="ltr">A PEI build plate can also be cleaned with water and soap or IPA to remove residue. To ensure the thermoplastic bed surface remains smooth in the long-term, you can also wipe it down with acetone once a month or so. It is important not to use acetone on a thermoplastic build surface too often as it can erode the material. Ultimately, a clean, smooth print surface can help the critical initial layer of a print to adhere.</p><p dir="ltr"><strong>Recommended reading:&nbsp;</strong><a href="https://www.wevolver.com/article/how-to-clean-3d-printer-beds-glass-pei-adhesive" target="_blank" rel="noopener noreferrer"><strong>How to clean 3D printer beds: Glass, PEI, Adhesive</strong></a></p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 626px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjUwMjg3NDIzNjcwLTNkX3ByaW50ZXJfbm96emxlLmpwZyIsImVkaXRzIjp7InJlc2l6ZSI6eyJ3aWR0aCI6OTUwLCJmaXQiOiJjb3ZlciJ9fX0=" width="624" height="437" class="fr-fic fr-dii" alt="3D printer nozzle and print bed"><span class="fr-inner" spellcheck="false">A clean build surface will help to promote good 3D printing bed adhesion.</span></span></span></p><h2 dir="ltr" id="isPasted">Method #4: Increase Bed &amp; Nozzle Temperature</h2><p dir="ltr">Temperature settings play a big part in the final quality of a 3D print. Thermoplastic filaments like ABS and PETG harden as they cool, but if printed layers cool too quickly, the materials can also shrink, which causes layers to pull away from the print bed and warp. Using a heated bed, especially for higher temperature materials, can therefore help to improve bed adhesion.&nbsp;</p><p dir="ltr">More than that, choosing the right bed temperature and nozzle temperature for different types of filament can also improve print outcomes. For example, ABS filament prints best with a build surface heated to between 90°C and 110°C and a nozzle temperature between 230°C and 260°C.[1] PLA, for its part, prints best with a heated bed of between 60°C and 80°C and with a nozzle temperature of 190°C and 210°C.[2]</p><p dir="ltr">Keep in mind that the optimal bed temperature may vary depending on factors such as the specific filament brand, bed surface material, and ambient room temperature. Therefore, it may be necessary to experiment with different bed temperatures within the recommended range to find the best setting for your specific setup. Another helpful tip to improve adhesion is to print the first few layers at a slightly higher temperature to ensure that they will stick. After those first layers, you can lower the bed temperature back to the recommended degree for the rest of the print.&nbsp;</p><h2 dir="ltr">Method #5: Use a Bed Adhesive</h2><p dir="ltr">Another reliable way to improve your 3D printer bed adhesion is to apply an adhesive directly to the build platform before you start printing. There are a number of adhesive products developed specifically for 3D printing, such as Magigoo and Stick Stick. Some of these dedicated adhesives are even designed with specific materials in mind. For example, Magigoo sells adhesive sticks tailored to polycarbonate (PC) and nylon (PA).[3]&nbsp;</p><p dir="ltr">However, there are also several DIY solutions for bed adhesives: many makers have found glue sticks to be a reliable option, while others use hairspray or blue painter’s tape (best for PLA filament) or Kapton tape (best for ABS filament) to create a grippier print surface. If you do decide to use an adhesive coating on your 3D printer’s build plate, it is important to apply them evenly and in moderation to avoid excessive buildup and to always clean your build surface after the print is complete, otherwise you risk glue buildup and an uneven print surface.</p><p dir="ltr"><span class="fr-img-caption fr-fic fr-dii" style="width: 627px;"><span class="fr-img-wrap"><img src="https://images.wevolver.com/eyJidWNrZXQiOiJ3ZXZvbHZlci1wcm9qZWN0LWltYWdlcyIsImtleSI6ImZyb2FsYS8xNjYxNDM1NTE2NTQyLWhhaXJzcHJheS5qcGciLCJlZGl0cyI6eyJyZXNpemUiOnsid2lkdGgiOjk1MCwiZml0IjoiY292ZXIifX19" width="624" height="459" class="fr-fic fr-dii" alt="Hairspray can "><span class="fr-inner" spellcheck="false">Hairspray, glue sticks, or dedicated 3D printer adhesives can improve first layer adhesion.</span></span></span></p><h2 dir="ltr" id="isPasted">Method #6: Adjust Speed and Cooling Settings</h2><p dir="ltr">If your 3D print isn’t sticking to the print bed, tweaking your print speed or cooling settings in slicer software can often help fix the issue. For example, setting the print speed for the first layer of your print to be slower than the rest of the build can promote better adhesion. A slower deposition rate for the first thin layer of a 3D print will help the filament to bond with the build surface.</p><p dir="ltr">Cooling settings can also influence print bed adhesion and are particularly important for materials that are sensitive to temperature changes, such as PLA. Proper cooling can help prevent the material from warping or curling as it cools, which can lead to poor adhesion. However, excessive cooling can cause the material to cool too quickly, resulting in weak bonding between layers. For PLA, it is generally recommended to use a cooling fan at 100% speed after the first few layers have been printed. For materials like ABS, which are more sensitive to shrinking, a lower fan speed or no cooling may be more appropriate.</p><p dir="ltr">For the best results, feel free to experiment with different settings and observe the results on test prints, making incremental adjustments until the desired adhesion is achieved. Keep in mind that the optimal settings may vary depending on factors such as the specific filament brand, printer model, and ambient room temperature.&nbsp;</p><h2 dir="ltr">Method #7: Use a Raft or Brim</h2><p dir="ltr">There are also other slicer settings that can be implemented to <a href="https://www.wevolver.com/article/3d-print-not-sticking-to-print-bed-heres-the-solution" target="_blank" rel="noopener noreferrer">improve bed adhesion</a>, such as <a href="https://www.wevolver.com/article/3d-printing-rafts-vs-brims-vs-skirts-how-to-get-started" target="_blank">rafts and brims</a>. Rafts and brims are features 3D printed alongside your part to improve stability and reduce the chance of warping. They increase the footprint of the printed model to encourage adhesion, which is particularly valuable when printing parts with a smaller base.&nbsp;</p><p dir="ltr">A raft essentially acts as a base to your 3D printed part and ensures that your print adheres to its surface, rather than the build platform directly. A brim, for its part, consists of a 3D printed border that connects to and extends from the edges of a 3D printed component. Brims are effective at anchoring the edges of a build to the 3D printed bed and are typically easier to remove than rafts. Most slicer programs, like Cura and Simplify3D, offer automated raft and brim features.</p><p dir="ltr">If you are using a raft or brim, it’s important to keep in mind that these 3D print features do require additional post-processing for removal. In some cases, the removal process is easy and can be done by hand, in other cases, you might need additional tools like cutters to remove the part from the structure.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/3d-printing-rafts-vs-brims-vs-skirts-how-to-get-started" target="_blank">3D Printing Rafts vs Brims vs Skirts: How to Get Started</a></strong></p><h2 dir="ltr">Method #8: Change the Build Plate</h2><p dir="ltr">Another method for improving first layer adhesion is to change your 3D printer build surface. Some desktop FDM 3D printers have a removable plate meaning that you can swap out the build plate for a new one should the original be damaged. But even if your print bed is in fine condition, it could be worthwhile to think about using different build surfaces depending on the material you are printing with.</p><p dir="ltr">A glass bed is a popular choice for 3D printer bed surfaces due to its smooth, flat surface and excellent thermal conductivity. The smooth surface allows for easy removal of prints once cooled and can result in a glossy, mirror-like finish on the bottom layer of the print. However, glass beds can sometimes struggle with adhesion, especially with materials like ABS, which are prone to warping. For this reason, many makers also use additional build surfaces like PEI sheets or Buildtak to improve first layer bonding. These can be applied directly to the existing build plate and are particularly effective for high-temperature filaments like ABS and PETG. Both PEI and Buildtak sheets provide a textured surface that promotes strong bonding between the filament and the bed, reducing the likelihood of print failures due to poor adhesion.</p><p dir="ltr">To maintain BuildTak and PEI sheets, clean them regularly with isopropyl alcohol or a similar cleaning solution to remove any residue or adhesive buildup. Inspect the sheets for signs of wear or damage, such as scratches, gouges, or delamination, and replace them as needed to maintain optimal print adhesion. When removing prints from the bed, use a spatula or a putty knife to gently lift the print without damaging the sheet.</p><p dir="ltr"><strong>Recommended reading: <a href="https://www.wevolver.com/article/3d-print-stuck-to-bed-what-to-do" target="_blank" rel="noopener noreferrer">3D Print Stuck to Bed: What to do?</a></strong></p><h2 dir="ltr">Conclusion&nbsp;</h2><p dir="ltr">These eight methods can help you with troubleshooting your 3D printer adhesion problems. Sometimes a single method—like adding a layer of glue to your print surface—will do the trick. In most cases, however, making various adjustments will result in the best adhesion and high-quality prints. In sum, ensuring a level 3D printer bed and a clean build surface, as well as using adhesive aids, and having the right print settings and printing temperature will have the best print results.</p><h2 dir="ltr">Frequently Asked Questions (FAQs)</h2><p dir="ltr"><strong>Q: What is the best bed surface material for 3D printing?&nbsp;</strong></p><p dir="ltr">A: There is no one-size-fits-all answer to this question: the best print bed material depends on the type of filament being used and the specific printer setup. Common bed surface materials include glass, BuildTak, and PEI sheets. Glass works well with most filaments but can benefit from additional adhesives. PEI sheets and BuildTak are also compatible with most filaments and can offer superior adhesion for common materials like ABS.</p><p dir="ltr"><strong>Q: How often should I level my 3D printer bed?&nbsp;</strong></p><p dir="ltr">A: The frequency of bed leveling depends on your printer's usage and the stability of its components. It is recommended to check and adjust the bed level regularly, especially before starting a new print or after making any adjustments to the printer's components.</p><p dir="ltr"><strong>Q: Can I use household items as adhesive solutions for bed adhesion?&nbsp;</strong></p><p dir="ltr">A: Yes, some household items, such as glue sticks and hairspray, can be used as adhesive solutions to improve bed adhesion. However, it is essential to apply them evenly and in moderation to avoid excessive buildup or uneven adhesion.</p><p dir="ltr"><strong>Q: How can I prevent prints from warping or curling during printing?&nbsp;</strong></p><p dir="ltr">A: To prevent prints from warping or curling, ensure proper bed adhesion by optimizing bed leveling, bed temperature, nozzle distance, print speed, and cooling settings. Additionally, using appropriate bed surface materials and adhesive solutions can help minimize warping and curling. For materials that are more sensitive to temperature fluctuations, such as ABS, consider using a heated enclosure to maintain a consistent printing environment.</p><h2 dir="ltr">References</h2><p dir="ltr">[1] Tractus 3D, 2020. “ABS Filament” [Internet] <a href="https://tractus3d.com/materials/abs/" target="_blank">https://tractus3d.com/materials/abs/</a> [Accessed April 13, 2022]</p><p dir="ltr">[2] Tractus 3D, 2020. “PLA Filament” [Internet] <a href="https://tractus3d.com/materials/pla/" target="_blank">https://tractus3d.com/materials/pla/</a> [Accessed April 13, 2022]</p><p dir="ltr">[3] Magigoo, 2022. “Magigoo Pro PA (Nylon)” [Internet] <a href="https://magigoo.com/products/magigoo-pa/" target="_blank">https://magigoo.com/products/magigoo-pa/</a> [Accessed April 14, 2022]</p>

Good first layer adhesion is critical to ensuring a successful 3D print.

Here are eight tried and true methods for optimizing your first layer adhesion with FDM 3D printing.

3D Print Not Sticking to Bed? 8 Ways to fix 3D Printer Bed Adhesion

Warping occurs when 3D printed parts curl away from the build plate

3D Printing Troubleshooting

Profiles