The availability of many different filaments with unique attributes is one of the best parts of 3D printing due to the considerable amount of flexibility it brings to the table, which allows the printing of objects that are suitable for almost every occasion when the filament selection is made correctly.
On the other hand, the diverse attributes that different types of filaments offer to the 3D printing process come not without a cost, with each filament having its own set of unique requirements for factors such as the print temperature and the print speed, potentially creating incompatibilities with the hardware of your 3D printer.
In today’s article, we will be examining whether TPU filament, known for its elastic properties that allow the 3D printing of functional parts such as gaskets, can be printed with the stock version of the Ender 3, which essentially is the most popular 3D printer on the market right now.
So, is it possible to print TPU with the Ender 3?
Even though the stock Ender 3 is equipped with hardware that is perfectly capable of printing TPU filament, the fact that it comes with a Bowden extruder can make the printing process slightly challenging due to the flexible nature of TPU, which makes it prone to getting stuck within the PTFE tube.
Moving forward, we will dive deeper into the compatibility between TPU filament and the Ender 3, discuss the optimal settings for printing TPU with the Ender 3, find out how to save TPU-specific settings in Cura for the Ender 3, and finally, troubleshoot the issue of stringing occurring while printing TPU filament with the Ender 3.
Can You Print TPU (Flexible) Filament with the Ender 3 (Pro/V2)?
Making sure that your 3D printer is compatible with the filament you intend to print is the first step you should take for a successful printing process, as an incompatibility between the two will cause your prints to fail from the get-go.
As TPU isn’t a very demanding type of filament in terms of the hardware it requires, not needing a heated bed, an enclosure, or high nozzle temperatures for an optimal printing process, the stock Ender 3 is more than sufficient to print TPU filament successfully with the hardware it has.
On the other hand, one drawback of the Ender 3 when printing with TPU filament is the fact that it comes with a Bowden extruder, which is known not to be the primary choice for printing TPU filament due to the flexible nature of TPU potentially causing it to get stuck within the PTFE tube, which can lead to an extruder jam in severe cases.
That being said, in most cases, it’s possible to overcome the issues that a Bowden extruder can create, especially when using a highly modifiable 3D printer such as the Ender 3, as there are quite a few quick modifications that will allow TPU to move more smoothly.
Below, you can find some of our suggestions that you can apply to allow your Ender 3 to have an easier time when printing TPU filament:
- Reposition the extruder of the Ender 3 to give the filament a smoother path to the hotend. With a more optimized extruder positioning, it’s possible to make the PTFE tube shorter and straighter, allowing the TPU to move within the tube in a much smoother manner.
- Utilize a 3D-printable direct-drive extruder mount to mod the stock Bowden extruder of the Ender 3 into a direct-drive one. Applying such a modification will eliminate the PTFE tube from the equation, allowing the TPU to make its way to the hotend without any problems.
- Print with TPU filament that has a higher shore hardness value. The higher the shore hardness, the less flexible the TPU filament will be, which will reduce the likelihood of it getting bunched up within the PTFE tube.
Finally, as it’s entirely possible to replace the stock Bowden extruder of your Ender 3 with a direct-drive one, you always have the option to completely eliminate the issues that printing TPU with a Bowden extruder can create without having to replace your 3D printer if nothing else works, which can be a good idea if you’re planning on printing TPU frequently.
What Are the Optimal TPU Settings for the Ender 3 (Pro/V2)?
Another significant part of achieving success while printing with TPU filament is to ensure that you have configured the print settings as best as possible, which can be especially challenging due to the flexible nature of the filament separating it from the standard options such as PETG and PLA.
Below, we have listed the optimal Ender 3 settings that we recommend using while printing with TPU filament:
- Hotend Temperature – 220°C – 250°C
- Heated Bed Temperature – 50°C – 60°C
- Print Speed – 20mm/s – 30 mm/s
- Travel Speed – 150 mm/s – 200 mm/s
- Layer Height – 0.16 mm (assuming that you’re using the stock 0.4 mm nozzle)
- Initial Layer Settings – Height: 0.28 mm | Temperature – 225°C – 255°C | Bed Temperature – Off or 50°C- 60°C
- Retraction – Distance – 2 mm | Speed – 20mm/s
- Cooling Fan – Off or 20% – 40% (Closer to 40% for overhangs and bridges as they require more cooling)
How to Configure TPU-Specific Settings for the Ender 3 (Pro/V2) in Cura?
Once you configure the print settings in a way that allows you to print TPU with your Ender 3 in a successful manner, the best thing to do is to save the settings as a custom profile, which will ensure that you will never lose the configuration and always be able to load it back whenever you need to switch between filaments.
Here is a step-by-step guide you can follow to configure TPU-specific settings for the Ender 3 in Cura:
- Navigate to the Prepare tab located at the top of the Cura window.
- Click the pane in the middle to bring up the Material settings.
- Click the Material dropdown.
- Hover over the entry “Generic” and choose TPU 95A from the list.
- Switch to the right pane to bring up print settings.
- Click the Custom button if you can see it. Else, skip this step.
- Click the dropdown labeled Profile, and choose the default profile you want to use as the baseline for the custom configuration.
- Apply the TPU-specific configuration of your choice through the Print Settings dialog as usual.
- Click the dropdown labeled Profile once again, and this time, choose the “Create profile from current settings/overrides…” option.
- Input the name you would like to use for the custom configuration, and click OK.
TPU Stringing Issue with the Ender 3 (Pro/V2) – What to Do?
As stringing is a reasonably common issue when printing with TPU, especially with 3D printers that have Bowden extruders, such as the Ender 3, there is a good chance that you will face this issue when you first start.
Below, you can find some quick tips that will prevent TPU from stringing while you’re printing with your Ender 3:
- Increase the retraction distance.
- Increase the retraction speed.
- Reduce the nozzle temperature to the lower end of the optimal range.
- Decrease the print speed to the lower end of the optimal range.
- Increase the travel speed.
- Utilize the coasting feature in Cura.
- Activate the wiping feature in Cura.
- Enable the combing feature in Cura.
- Ensure that the TPU you’re printing is completely dry.
When modifying the retraction distance and the retraction speed, in particular, we highly recommend performing minor adjustments and running tests after each adjustment, as unintentionally applying too much retraction to TPU is very easy and can lead to the jamming of the hotend.
As not every 3D printer is compatible with every filament due to factors such as the hotend of the 3D printer not being able to supply the temperature required for the filament to reach its melting point comfortably, it’s vital to always compare the specifications of a 3D printer with the requirements of the filament before committing to a purchase.
To quickly recap, other than the fact that TPU filament and Bowden extruders don’t really play well, potentially creating issues for the 3D printing process, which is a Bowden extruder-specific problem rather than an Ender 3-specific one, the Ender 3 checks all the boxes for successfully printing TPU.
In the worst-case scenario, where printing TPU with your Ender 3 becomes too much of a struggle due to the issues caused by the Bowden extruder, you can always perform some modifications to make the process more reliable or even replace your Ender 3’s stock Bowden extruder with a direct-drive one.
Mike started his 3D printing journey with the Anet A8 when it first came out back in 2017, and has been obsessed with 3D printers ever since. Nowadays, he primarily uses his Ender 3 to print functional parts that make his life more convenient whenever possible.