Fine strands of filament or small particles of material in the Bowden tube cause friction and will eventually lead to under-extrusion and failure to print properly. Follow this guide to properly clean the Bowden tubes.
Cleaning the Bowden tube
You can easily clean the Bowden tube by following these steps:
Tip: Pay attention to the orientation of the first Bowden tube when removed from the printer. One side is chamfered for easier entry of the filament. this side should be inserted into the feeder.
1. Remove the material from your Ultimaker. Refer to the 3D printer manuals for step-by-step instructions
2. Remove the clamp clips from both sides of the Bowden tube. One is on the print head and the other is on the feeder
3. Loosen the Bowden tube by pressing the tube coupling collet and pull the Bowden tube out
4. Use a bit of filament to push a small piece of sponge or paper through the Bowden tube to push the small particles out. Repeat until the Bowden tube is clean
Tip: To clean the tube most efficiently, make sure the sponge or ball of tissue is a tight fit inside the Bowden tube. Note that if it is too big it will be difficult to push through.
5. Re-install the conical end of the Bowden tube in the tube coupling collet of the feeder
6. Re-attach the clamp clip while applying pressure to the Bowden tube
7. Re-install the other end of the Bowden tube in the print head. Use a rotational movement to ensure it is completely inserted in the white coupler
8. Re-attach the clamp clip while maintaining pressure on the Bowden tube