3D printer filament guide with Lego pulley - make your own simple and effective Ender 3 upgrade

The Creality Ender 3 Neo is a great budget printer, but it does need quite a bit of tinkering to get the best out of it, and here’s a really easy - and cheap - way to significantly improved its performance.
My specially designed, 3D printed filament guide takes the pressure off the standard plastic extruder by ensuring the filament is fed in at a shallower angle, reducing friction, and the likelihood of miss-printed layers causing the whole print to fail.
Mk2 is even better, with a Lego pulley wheel to further reduce friction for confident printing of even the longest jobs.
If you are inspired to make your own, the .stl file for the design can be downloaded from paterpracticus.com/downloads
The Lego spoked pulley wheel (part no 30155) and axle (connector peg 39888) can be easily sourced from ebay or other suppliers.
0:00 - Introduction
0:16 - The problem
0:36 - Introducing the filament guide
0:38 - A hard working extruder
1:00 - A helping hand
1:15 - The concept
1:25 - The detailed CAD
2:00 - Slicing with Cura
2:27 - Printing the prototype
2:40 - Mounting on the printer
2:54 - Initial testing
3:11 - Refining the guide
3:28 - Download link for Mk2 .stl
3:37 - Slicing Mk2
3:43 - Printing Mk2
3:48 - Preparing the finished print
4:20 - Fitting the Mk2 guide
4:30 - The perfected filament guide in action

[@PetterAstrom]

Thumbs up for the delightful attitude!

[@paterpracticus]

Always delighted when something works out.

[@johnfeistner467]

This is genius

[@paterpracticus]

Thanks. A link to the .stl file is in the description if you want to make your own.

[@FixTechStuff]

I like your style. The lego move was genius, I would not have. thought of it.

[@paterpracticus]

Thank you. The Lego wheel is perfect - smooth running and easy to fit. I really can now confidently leave the Ender running for longer prints without always checking up - even with the standard extruder.

[@HonthaVinber]

The idea is great - maybe the babysitting could be eliminated even on longer prints if it was atached to the x axis gantry? that way it would rise up along with the extruder

[@paterpracticus]

I had thought of that, but there didn’t seem to be any point at which to easily attach it. I was also concerned that adding anything to the moving parts might upset the mech. So the side frame seemed safest. Even then, it only really needs to be moved up during the tallest of prints.

[@HonthaVinber]

@@paterpracticus Fair points. Best I can think of is copying what they did with the drag chain I used on my printer, which can be attached via the m3 screws on the bottom of the extruder motor. here's the drag chain i'm talking about: www.thingiverse.com/thing:5205630