Prusa i3 MK4 back filament wheel

I have a drybox under my i3 MK4, and the normal spool holder is not enough to ensure that the filament goes smoothly into the Nextruder group.

So I created this filament wheel, using a print in place bearing found on Onshape. 
The two spacers are good to set the filament in line with the standard prusa filament holder.

Instructions:

• Printing the bearing in place could be difficult, I've printed with prusament PETG and some parte were stuck but managed to free them. I suggest Z-seam randomization on Slicer.
  Moving with some force al the “cylinders” helps free up the mechanism.
• The bigger the wheel the better it works, I printed a 140mm ext. diamater wheel but noticed that a 160mm would be better because of the tangent angle forming with the filament holder
• To mount all up simply inscrew the filament holder and insert:
  • the 53mm spacer
  • the bearing
  • the wheel on the bearing
  • the 21.5mm spacer
• All set!

Enjoy printing without problems on filament feed form the back.

Print in place bearing source is here.
You can customize it, for this case i've used:

• #internal diameter: 23.8 mm
• #thickness: 21 mm
• #height: 15 mm

Printed with 0.4 nozzle and 0.2 resolution.