Ender 3 Filament roller guide top and bottom

thingiverse

Edit 23/4/2020: I redesigned the dovetail for a better fit and added a hole that allows the stock M5x45 bolt to secure it in place with the Ender 3's top rail. Due to size differences, I also reworked the support arm, but the old one will still fit - albeit not flush. The photo shows the original flat arm; I haven't had time to print a new one yet. I modified the Filament roller guide by Holspeed to use an M4 bolt thread and created a matching top guide in a similar style. The top filament guide connects to the Ender 3's aluminum frame in two parts: a small dovetail connection and a filament guide that comes either flat or angled up 30 degrees. The flat arm is suitable if your spool is mounted to the left of the Ender 3's top frame, while the angled arm is better suited for spools closer to the right side - or when supporting the spool in a horizontal manner. Check out my Horizontal Spool holder at https://www.thingiverse.com/thing:4314752 if interested. Each support requires two of the 4mm bearing inner race guides; I've included three bearing outer races with different diameters (22.0mm, 22.2mm, and 22.4mm) - just match which one fits best onto your bearings, likely 608 skateboard bearings. You'll also need one M4x20mm bolt and nut for each guide used. I've included the SketchUp file if you'd like to further modify it. I printed with 7% supports; see the final photo for how I oriented the parts during printing.