Filament guide for CR-10S, Ender-3, Alfawise U20, etc.

The lube/grease on the Z rod can ruin your prints if touched by the filament. This guide helps preventing this behavior by running the filament directly inside the extruder.
It prints easily in less than 20 minutes and it is compatible with many CR-10 style 3D printers, including the Creality Ender 3 and the Alfawise U20/10.

Here on Thingiverse you can find some other designs, but I like none of them. Some requires screws, some others are too tight. The one I designed leaves the filament some freedom, but it will never touch the Z rod.

In the picture you can see this filament guide upgrade mounted on my Alfawise U20 and Creality Ender-3.

UPDATE 29/01/2019 | Added a variant for 3D printers with spool holder mounted on the top of the frame.

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<a href="https://www.thingiverse.com/AdryJay/collections/alfawise-u20">U20…