Introduction
After testing various types of flexible filament (TPU and TPE) in our DunaTech workshop, I can confidently say working with this material is challenging, but the results are worth it. This type of filament is perfect for flexible parts like phone cases, seals, or wheels. However, not all printers are designed to handle it without specific adjustments. Here’s how to do it correctly.
Preparing Your Printer
Before you start printing flexible filament, make sure your printer is ready for this material. In my tests, Bowden extruders were less effective than direct-drive extruders due to the distance between the motor and the hotend. Here are the essential steps:
1. Use a Direct-Drive Extruder
– **Advantage:** Shorter distance for the filament to travel, reducing the risk of clogs.
– If your printer has a Bowden setup, consider upgrading to a direct-drive extruder.
2. Adjust Flow and Speed
– **Recommended Speeds:** Keep the print speed between 20-30 mm/s to prevent filament tangling.
– **Flow:** Adjust the flow to 105%-110% if you notice layers not adhering well.
3. Use a Proper Nozzle
– Opt for nozzles of 0.4 mm or larger to avoid blockages.
– Ensure the nozzle is clean before starting.
Software Configuration
The slicing software is key to achieving good results with flexible filament. When we tested pre-configured profiles in Cura and PrusaSlicer, we noticed they required specific adjustments. Set the following parameters:
1. Minimal Retraction
– Reduce retraction to 1-2 mm (or disable it) to prevent the filament from twisting inside the extruder.
2. Layer Height
– Use a layer height of 0.2 mm for a balance between detail and adhesion.
3. Travel Speed
– Set a low speed (~60 mm/s) for non-printing movements.
Useful Tips for Printing Flexible Filament
Here are some tricks we discovered in the workshop after printing over 10 kg of TPU:
– **Use a Heated Bed:** Keep the bed between 50-60 °C to improve adhesion.
– **Additional Adhesives:** If the filament doesn’t stick well, try Kapton tape or glue stick.
– **Storage:** Store the filament in an airtight bag with desiccant to prevent moisture absorption.
Troubleshooting Common Issues
Even with the best setup, problems may arise. Here’s how to solve them:
1. Extruder Jams
– **Cause:** Printing speed too high or excessive retraction.
– **Solution:** Lower the speed and reduce retraction.
2. Layers Not Sticking
– **Cause:** Insufficient flow or layer height too high.
– **Solution:** Increase the flow to 110% and set the layer height to 0.2 mm.
3. Filament Not Advancing
– **Cause:** The filament is too soft for the Bowden system.
– **Solution:** Switch to a direct-drive extruder.
FAQ
Can I use flexible filament with any printer?
Not all printers are compatible. Printers with direct-drive extruders perform better than Bowden setups.
Do I need a heated bed?
Yes, a heated bed at 50-60 °C improves the adhesion of the first layers.
How can I prevent the filament from breaking inside the extruder?
Lower the print speed and adjust the retraction to minimize stress on the filament.
Conclusion
Working with flexible filament requires patience and precise adjustments, but the results are impressive. If your printer is properly set up and you follow these tips, you’ll be able to print flexible parts without issues. If you have more questions, leave a comment or check out our article on how to use a Sovol filament dryer to keep your materials in perfect condition.
— The DunaTech Team