B-Struder - Bowden extruder with 40Tgear + U604ZZ bearing for 1.75 filament

I had an all aluminium extruder (from ebay), and it worked fine, it was just a bit off whenever I needed to insert a new filament, because of the gap between the gear and the bowden tube, so the filament went everywhere except were intended...

Looking around Thingiverse, I found some great designs I liked, so I chose and studied these next 3 good examples, mixed them to fit the parts from the Ebay aluminium extruder that I had, and then tweaked it some more to get what I desired:

+ B'Strud