This is a bering I designed. The center hub is will fit an 8mm hex wrench, or any 8mm hex axel. Bering designed to print in place and provide resistance to slew superior to ball bearings or "barrell" berings. Also each individual bering has a small through slot to assist in breaking free if needed.
NOTE: This bering actually performs better if/when a bering or 2 breaks and falls out.
3 berings can fail and the hub will still be held in place (and maintain suprisingly little slew), loose 4 bearings and very soon they will all bunch up and there will be enough space for the hub to come free.
This can be mitigated by increasing the diameter of the inner shaft of each bering, which also means re-building the outer race (at least)
NOTE this bearing is designed with .2 mm gaps between berings and races. This tolerances is to allow for "sloppy" printers or materials with significant expansion/shrink and variation issues.
This bering has been successfully printed several times with PTEG on a creality ender3
at 0.15 layer height with PTEG I was getting axial slew no more than 0.5 degrees, and surprisingly resistant to slew.
Props go out to Gear Down For What #geardownforwhat makers muse and AVE for the inspiration.
I am including the bering as one RTP unit, and the hub, individual bering, outer race as individual files.
Also this is a public design on tinkercad... full build history ungroup-regroup to your heart's content.
any any : recommend PTEG
berings work with solid down to 20%
These bearings work at a print resolution of 0.2 mm, I have not printed at a lower resolution, but the bearings are designed to function all the way to 0.5mm layer hight
8mm hex wrench is ideal for breaking this free
also jewelers screwdriver or small file can be handy for a stubborn bering
Berings are pretty simple things to make, With this type of bering the trick is the angles. Instead of trying to calculate the angle on the ID and OD of various parts, use the RATIO of cone diameter to height. That way you can scale your bering up and down, change it's dimensions etc. The outer race is created by making a negative, which is just a very large version of an individual bering, then using that as a hole for a cylinder.