A two part holder for an LM8UU type bearing.
There are now two variations. The first relies on screwing the holder into the plastic. The second allows you to insert 4 M4 nuts and screw the holder in using those instead.
You'll want to use 2x Holder_Std or 2x Holder_Nuts to hold most bearings. If a bearing holder is required to trigger an endstop then you can use 1xStop_End or 1xNuts_Stop_End on the side that needs to trigger. It has has a more standard profile in the first couple of millimetres to serve this purpose.
I am currently using these for the Y carriage of my 3D printer (an Anet A8 - now AM8)
18/02/2018 - I've now been using the nut based variant in my printer on the y axis for several weeks and on prints as long as 24 hours. I was inspired to make this variation following a request on my other bearing holder design.
PLA 0.2 or 0.24mm, ABS 0.16mm. (0.4mm nozzle)
30-35% but feel free to experiment.
3 outer perimeters at 0.4mm nozzle size recommended for the version without nuts to give you enough material to cut a solid thread into.
2 outer perimeters for the Nut holding version
It is suggested to tap the holes in the bottom with a 4mm thread to ensure a secure fit. It's possible to just force the screw into the part when installing but this would risk stripping the hole leaving you with a hole which is then too large for the screw to grip. (In a pinch you can slide a slither of plastic or two into the sides of a hole and hold them in place while inserting the screw - this will quite often hold sufficiently in the short term.)
2 M4 nuts (hex) per piece required for the Nuts parts so 4 M4 per bearing.
Far more boolean operations than were strictly necessary - designed using OpenSCAD.