Bearing Filament Guide for Prusa Mk 4

Credit to the author, Bobstro on Thingiverse for the original idea and framework. The two models shown did not fit together - unusable. The frame clip has a 'tip' and there is no hole for it in the bearing carrier to fit into.

I created a hole in his model to fit, then realized the wider cylinder holding the tip was not tall enough to provide any retention. Even making that cylinder taller would not hold the bearing carrier in place so I made the cylinder taller then provided a ring detent in it, then added a beveled retention sleeve to the bottom of the carrier and put slits in it to let it flex to go over the clip.

This was my first time modeling something so small with all those changes - thanks to TinkerCAD for the tools and the author for the original models and ideas (I did message him but no response and this model was about 4 years old).

I printed in PETG with a .15 layer height (.20 bottom layer) and used supports for the clip (but not the carrier or swivel cap). I used the Amazon link below for the bearings - you can still get them as of 4/24/24. I printed the clip at 98 percent for a slightly tighter frame attachment (there's no bottom raised retention bevel but the top frame attachment holds it well). You could run it at 97% for a tighter fit and I believe the carrier would still attach firmly.

https://www.amazon.com/dp/B0B6WQQXS9?ref=ppx_yo2ov_dt_b_product_details&th=1

It does clip together with a bit of force, It could have used some smoothing and lithium grease on the mating surfaces for a bearing smooth spin but this does work as is and turns easily with slight pressure after 'working it' a bit.

There is no picture for the 'swivel cap' but it attaches on the top of the carrier and rotates down into place (there's a stop it rests against). I oriented it all so the filament would pull against the closed cap mating position and the clip as above. Use pliers or a socket and small hammer to pop the bearings on the two pins - they are sized correctly.

Please improve and offer suggestions/remixes. This is low height and even with the body of the clip facing to the front of the printer, the extruder still can rise to its highest point without contact.

EDIT TEXT

Improved the frame clip with an attachment ring for the bearing carrier.  Improved the bearing carrier to actually fit the original frame clip and added a beveled retention component to clamp securely on to the frame clip.