The Ender 3 line of printers ( the Ender 3, Ender 3 Pro, Ender 3 V2, and Ender 3 S1,) has quickly become a go-to for many in the field, offering accessibility and affordability that surpasses similar machines. Unfortunately, their ability to deliver results comes with one major obstacle: the common problem of under-extrusion.
Under-extrusion is a significant concern for anyone employing 3D printing processes, as it generates weak and aesthetically displeasing parts. These gaps severely weaken the structure of your part and make it much more vulnerable to breaking or cracking; meaning one careless move could ruin hours of hard work.
If you’re a user of an Ender 3 printer and having trouble with under-extrusion issues, don’t worry – there are several tips and tricks available to get back on track. By reading our article, you will be armed with all the knowledge you need to successfully combat any under-extrusion problems in no time.
Before you get stuck into the fun stuff, take a few minutes to go through the basic steps for assembling and calibrating your Ender 3. Check that the extrusion multiplier and filament diameter are correctly specified in your slicer too – this will help to guarantee successful printing down the line.
Tip #1: Adjust Temperature Upwards, Reduce Speed
The total fabrication process is impacted by every printer setting. In general, a larger flow rate is essential to guaranteeing that more material will emerge from the nozzle during production. The temperature can also be raised in order to increase filament flow, though.
But, If your filament is exposed to excessively high temperatures – that is, more than 10 °C over your print temperature – you may experience phenomena such as oozing and stringing. This can be remedied by making simple adjustments, such as increasing the flow rate of the filament by 5% and increasing the temperature by 3 °C until you get the desired results.
One other reason could be that the speed at which you print is too fast. Even if you only slow down by 20 millimetres per second, this can make a huge difference in how often you succeed.
Tip #2: Nozzle Cleaning and Adjustment
The most common culprit is often a partially-clogged nozzle, which happens when foreign particles in the filament that cannot be melted get stuck in the nozzle and block it. To catch this issue early, extruding some filament and checking if it comes out straight or curled is the simplest way to diagnose the cause and then proceed to clean the blockage quickly and efficiently.
The first course of action when dealing with a clog is to attempt “atomic pulls”. This involves taking the nozzle off and pulling the filament out in small pieces. If you’re lucky, this will clear the clog. If not, you have a few other ways to go about it.
For example, pushing a needle through clogged areas can work if practised with care. As for preventative measures, having a cleaning filament on hand can help keep your machine working trouble-free by periodically melting out particles stuck in the nozzle or hot end.
The Z distance, which tells how far away the nozzle is from the print bed, is another thing to think about when it comes to the nozzle and the extrusion process. If it isn’t set up right, the flow of filament can be slowed down, which can lead to problems like a thin first layer and sounds like the extruder is skipping.
If you want your 3D printing projects to turn out perfectly without fail, it’s important to ensure that you set your Z distance properly. This requires a two-step process: first, properly levelling the print bed on your Ender 3; and second, adjusting the Z offset setting in the slicer, or through the LCD if need be.
Tip #3: Installation of a New PTFE Tube
Problems with extrusion are often hard to figure out and don’t make sense. Filament jams can be a sign that something is wrong, but it’s easy to get frustrated by how often they happen and miss the real problem, which is the PTFE tube.
The PTFE tube, more popularly known as the Bowden tube, is a critical component of 3D printing. It enables filament to travel from the extruder to the hot end and produces higher-quality prints. Though it’s much longer on Bowden extrusion printers, like the original Ender 3 and the 3 Pro and V2, only a small section is required for direct extrusion 3D printers, such as the Ender 3 S1. It not only increases ease of use when building models with your printer but also enhances accuracy during fabrication and the long-term durability of every part created with it.
Filaments come in various types and sizes and not all of them are created equal. If a filament claims to have a ±0.05-mm tolerance, this is likely not accurate and consistent across the length of the filament. PTFE tubes with tight tolerances make for a more difficult path for the filament to flow through and can cause under-extrusion.
The simplest way to achieve this is to attempt manually extruding the filament; no additional testing devices are needed. Without any resistance, you should be able to push the filament into the tube; if you have to exert any effort, it’s likely time for a new tube. Doing periodic checks on your PTFE tubing gives you confidence in the accuracy and standard of your results.
Tip #4: Rectify Hot End Issues
When you feel you have exhausted all other options and are still unable to resolve your under-extrusion problem, the hot end of the 3D printer might be to blame. Take the PTFE tube of your Ender 3s hot end for example. It is intended to sit flush against the nozzle surface at all times, but sometimes faulty couplings or imperfect quality control can result in a gap between them.
As the plastic filament is pushed through, it is typically directed directly at the nozzle. However, if there is too much space between the PTFE tube and the nozzle, then the filament can ooze out into this gap instead, leading to reduced flow and even a blockage over time.
L3D_Help_Guide’s hot-end fix is the most trusted and reliable solution for any user with a faulty hot end. Their unique step of installing a washer to secure the tube in place ensures that it sits flush with the nozzle for optimal performance. An alternative solution could be to upgrade your couplings and put the whole setup together properly as well, but this won’t guarantee a perfect alignment as L3D_Help_Guide does.
It’s essential to remember that the options described will probably not work for you if you own a Creality Ender 3 S1. As this model’s hot-end assembly, which is integrated into the extruder, is different, the required resolution must be determined using alternative methods. Making your own washer or finding a different solution might be required if you want to fix your problem with the Creality Ender 3 S1 model.
Tip #5: Upgrading to a New Extruder Assembly
Upgrading the stock extruder setup for the Ender 3 (original, Pro, and V2) is one of the best decisions you can make for this printer. The plastic extruder that comes with it may be initially cost-effective but wears out quickly. Whether you’re just getting started in 3D printing or an experienced veteran, switching to a metal extruder like the direct extrusion option on the Ender 3 S1 (known as the Creality Spider) will give you much more stability and reliability.
A common problem that many 3D printer users experience is filament grinding due to the extruder. This can be caused by the extruder cracking over time and losing its spring tension, which prevents the gear from gripping the filament correctly and consequently causes extrusion problems.
Installing a new metal extruder could be your answer to grappling with extruder-related issues. It’s much more rigid and resilient than typical plastic extruders, meaning it will last much longer over time.
It’s important to note that the Ender 3 S1 comes with an impressive all-metal extruder assembly which makes it incredibly capable. However, if you’re seeking even better performance then it could be worth considering changing out the extruder for a newer version if you have an older Ender 3 model, such as the original, Pro or V2.
Adding washers to the default extruder’s spring is an alternate way to completely replace the extruder on your Ender 3. Installing washers to increase the grip of the filament on an extruder is a fast and inexpensive way to get your 3D printing projects back on track. Regular screw washers from any hardware store will do just fine. You’ll be able to stick them onto the spring at the base of the extruder assembly in no time.
Tip #6: Extruder Calibration for Optimal Performance
It is essential to have the correct extruder settings for a 3D printer in order to get your prints to look just the way you want them to, but this can be quite a challenge. Every printer has its own unique parameters when it comes to extrusion, meaning that what works on one machine might not work quite as well on another. Too much stepper motor rotation resulting in over-extrusion, or too little rotation and an under-extrusion will both have deleterious effects on the final print.
Go to our extruder calibration guide for further instructions on how to solve these issues. This comprehensive guide explains every step of the process in detail. You’ll be able to measure exact quantities and determine if your printer is pushing as much filament as it thinks it is.
If you’re among the users of the Ender 3 Pro 3D printer, here’s a special note that might just save your next weekend project – take a look at the “E in mm3” setting in the Control > Filament menu. Leaving this setting on by default can cause under-extrusion issues and enough frustration to make you put down your projects altogether. After double-checking that it’s off, you can start printing confidently knowing that your prints will come out better than ever!
Tip #7: Raising the Hot End Fan Speed for Improved Cooling
Last but not least, under-extrusion may occur if some hot end components of your 3D printer are improperly cooled. Keeping the hot end of a 3D printer cool is essential for producing good-quality prints. The hot-end fan helps to do just that, but only when it has been properly installed. This fan works by regulating the temperature in the upper part of the hot end assembly and ensuring that the filament doesn’t melt too soon. It’s important to note that this fan should not be confused with the part cooling fan, which is a separate device designed for keeping individual parts or components cool.
If the hot end fan fails to function properly, the heated filament will begin to melt before reaching the nozzle, resulting in a blockage and incomplete parts due to under-extrusion. This is known as “heat creep,” and it is a preventable problem. It can be avoided by ensuring that the hot end fan is running at the appropriate speed to maintain the filament stable and flexible.
While part cooling fans are usually adjustable in a slicer, the hot end is often managed through the firmware. As such, if you’re comfortable making edits to your printer’s firmware, adjusting this setting can be an easy task. To increase the extrusion volume in your prints, try increasing this parameter (usually set as a percentage out of 255) and see how that impacts your results.
And if the hot end fan is not sufficiently cooling the upper portion of the hot end even at 100% speed, you might wish to switch hot end fans. There are plenty of alternative fans out there that are compatible and offer enhanced cooling performance, so it’s worth checking them out. Some of these aftermarket fans can be up to 20% cooler than the stock options on the Ender 3 Pro/V2/S1, ensuring optimal temperatures when printing at 100% speed.
I am Bheema Shankar. I have worked on SLS, CJP, DLP, SLA and FDM technologies at Think3D. Currently working as Process and application engineer at VEER-O-METALS PRIVATE LIMITED. I am always fascinated by the process of creating things layer by layer. This fascination led me to pursue a career in 3D printing technology. I am passionate about how 3D works and enjoy exploring new ways to improve the 3D printing process.