Best Y-axis Bearing Holder

I have tried many y-axis bearing holders and never could find one that performed well. The MK3s U-bolts were too finicky to tighten just right and inevitably lead to the bed getting loose and rattling. The MK3s+ metal straps and many other of the printable fully enclosed bearing holders caused bearing misalignment. They cause loud rattling of the bed as each ball in the bearing has to wedge between the rail and the bearing race. Back to basics....

Simply putting the bearings on the rails, the rails on the frame, and the y-carriage on the bearings enables perfectly smooth movement without any bearing rattle. That confirmed for me that whatever the solution for a good bearing holder, it could not space the bearing off the slots in the y-carriage. Any good bearing holder had a simple task: Secure the y-carriage onto the bearing without adding any forces that could cause misalignment or the bearing casing to be deformed. Forces needed to be distributed uniformly and some amount of stretch in the bearing holder was needed to maintain tension over the long-term.

I came across FiveAngle's design which seemed like a good candidate but needed one adjustment: extending the screw hole all the way through the base of the strap so that it's ready to use without any drilling. This leaves intentional interference between the screw hole outside of the strap. When installing an M3x16 from the top of the y-carriage, it will plow perfectly cut threads and maintain perfect tension without needing any nuts. The strap is slightly undersized so as the screws are tightened, it will stretch around the bearing, distributing uniform pressure on the bearing for no deformation. The base of the strap flattens against the y-carriage and everything is perfectly tensioned. No excess forces are put on the bearing, and perfect alignment with the rails is maintained.

To install:

1. Clip a bearing holder on each bearing. The edges of the holder have a raised lip that goes into the slots on the bearing for longitudinal security.
2. put the bearings on the rod
3. Install the rods on the printer frame, keeping the y-rod holders screwed in, but not fully tightened.
4. Set the Y-carriage on the bearings, lining up the holes on the bearing holders for screws.
5. Install (6) M3x16 screws, evenly tightening and testing for smooth carriage movement. Tighten until they natural stop. Do not go crazy tight or the plastic could strip out. I think this is one of the keys to success is that the bearings are being secured in actual operation, perfectly aligned. The securing screws are accessible from the top without having to hold a nut on the bottom. Super easy, hard to mess up.
6. Tighten the y-rod holders while moving the carriage back and forth.

I have not found any other bearing holder that is easier to install correctly than this one. The Y-carriage glides as smoothly and with the least friction of any solution I've found.

Printed in PETG with 2 walls and 100% infill.
(2) M3x16 screws per bearing holder

Print instructions

Print in PETG, 2 walls, 100% infill