Filament Pully for Ender 3 direct drive or similar

Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5714574.

I converted my enter 3 to direct drive but didn't have room to mount the spool above the printer. This meant the filament came in at a sharp angle and the spool would start rocking as the head pulled the filament back and forth. 

This uses 6mm airsoft BBs as bearings. To assemble, place one half of the hub inside the wheel and fill with BBs, place other half of hub on top then snap the base on top and snap the base on top to lock everything together.. Mount to rail bar with T-nuts. The guide keeps the filament from jumping off and has a gap that can be turned down to allow the filament to be removed without removing from the print head.