608 Bearing - Planetary Herringbone - print in place

Greetings from Canada!

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I decided to try my hand at making a print in place bearing using a planetary gear system and herringbone teeth for stability.  This is the end result and I am happy to say that it has worked for my needs.  A herringbone planetary gear will have higher resistance than your typical bearing, and it has a bit more noise.  

608 bearing dimensions - 22mm OD x 8mm ID x 7mm height.  

I was successful in printing this with a .4mm nozzle, 0.2mm layer height, and 15% infill (although 2 walls meant that this is basically 100% solid.  The only setting that you may need to modify is the "slice gap closing radius" if your slicer is joining pieces (check the preview to ensure that the pieces are indeed separated at the top and bottom most layers). - When my slicer inappropriately joins pieces, I find that I must change the slice gap closing radius to 0.001mm, and then I haven't had any issues.

Finally, after printing this out in PETG, I did need to lightly sand the top and bottom layers.  There was enough of a connection between the center (sun gear), the planets (central gears), and the outer (ring gear), that I needed to give a light sand to break that weak connection.  Then, I was able to rotate the bearing and I was happy with the outcome

I have included two STLs - high tolerance and low tolerance - the low tolerance has slightly higher resistance but less play.  The high tolerance bearing spins with less resistance but has a bit more wiggle room.  Nevertheless, I have found that these are more stable than the 608 bearing using rollers that I have made (although there is more resistance).