published: December 20, 2020 — last modified: October 23, 2025
I had several times problems with a clogged nozzle, and recently found particles on new filament spools, which could have to be the reason for it. So I checked different filter solutions, but found no one fitting perfectly into my setup.
Table of Contents
To reach these goals, I combined the filament feed-through with the filter. It provides a solid attachment point on the top of the enclosure. Around this point, I designed the two halves of the filter itself, which uses four strong neodymium magnets to firmly hold in place.
The magnets are printed into the filter shells, a technique I already used for several projects.
Each side of the filter contains a sponge, which is covered with a microfibre cloth.
The sponge provides the required pressure, but the microfibre cloth is actually in contact with the filament. There is almost no friction, but even smallest particles and dust get caught in the cloth.
If not used, the two shells also hold together at the sides.
You can download the model files and the Fusion360 design here:
The ZIP archive contains STL files, which are made for a 16mm hole in a 10mm thick enclosure. If you have different dimensions, use the Fusion360 design to adapt everything to your needs.
LR2085 Filament Feed with Filter by Lucky Resistor is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
All parts are best printed using PETG with a layer height of 0.15mm. The feed-through parts (101 and 102) are obviously printed with the disc on the print bed.
The filter shells (2 × 103) are printed with the flat side to the print bed. You need to insert a pause command, just before the holes for the magnets are covered.
Best, you make a test print to check the correct hole sizes for your magnets. They need to be inserted with some friction, otherwise, they will snap out of the holes if the print head moves over them!
If none of the existing filament filters worked for you, please give this design a try. Using the magnets, it will snap on and off with ease and it has no noticeable friction on the filament.
If you have any questions, missed information, or simply want to provide feedback, feel free to comment below or contact me on Twitter. 😄
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