Feedback is appreciated. I am in the process of building a Full Bear and came across the Y bearing holders designed by pekcitron. I printed and liked his holders so much that I wanted to use them on my standard MK3s frame, but they are not compatible. This is my attempt to remix his design to make them compatible with the original Prusa i3 MK3/s.

Features:

Support Prusa i3 MK3/s
Strong and solid bearing holders
Compatible with standard LM8UU bearing, Igus RJ4JP, Misumi and Motedis bearings
Bearing are perfectly centred (holes of MK2 Y carriage are not centred)
Clean shape to avoid any printing artifacts
Require a perfect alignment of the Y axis

Hardware needed:

6x M3x18mm with 6x "normal" nuts and blue Loctite

Installation:

Do not tighten them too much! Follow the same instructions as original Prusa i3 manual: http://manual.prusa3d.com/

Update April 24th, 2019: I just printed and tested the design. The holder cleared the frame; however, the nuts didn't...barely. The new files have been adjusted to recess the nuts by an additional 1mm.

Update April 27th, 2019: I am happy to report that everything clears the frame! At this stage, these Y-bearing holders will work. However, I am not sure how well they will hold up. I am interested in getting feedback from anyone who installs them.

You require 6x M3x18 screws and 6x regular hex nuts. My preference would be to use nylock nuts; however, they don't clear the frame. Because the screws barely grab the nut, I also recommend using some blue loctite to secure the nut.

Also note that the nut recess creates a hole in the holder, due to the resolution. This hole is not present in the drawing and appears not to affect the holder.

Update May 7th, 2019: I just removed the "work in progress" status. I have been using the bearing holders without any issue since April 27th. One positive thing I noticed about these holders is that they are slightly quieter than the stock u-bolts.