Ender 3 Filament Roller Guide (Remixed)

From https://www.thingiverse.com/thing:3052488

Ender 3 family's spool holder is mounted on top which made a steep angle of filament entry. This can result in unsmooth filament feed into the extruder.

the change is done by the following list

• the filament roller bracket is lengthened by 15mm to let
  the filament feed into the dual gear metal extruder more naturally
• Adding another fillet bridge to the filament roller bracket
• The socket in the bracket is expanded for easier insertion into the Z gantry
• The roller is reconfigured by increasing the outer diameter
  to protect the filament from slipping out of the roller groove

The material in the following list is required

• M3*20mm bolt
• M3 nylon lock nut
• 608 ball bearing