Igus linear bearings for 7mm shaft. For some unknown reason (at least, for me...) there is no bearing available for 7mm shafts, which I happen to have some in first class quality (taken from high end laser printer cartridges). I'm planning to use these shafts in my own 3D printer build, but in absence of factory made bearings, I had to step on my own way :) I started from the 8mm version dimensions, changing the internal features in order to accomodate the 7mm shaft.
There are two versions: at the AN version, the air gaps' radial walls have 5.4deg angle (lines cross in the center point) while the SQ version follows the original IGUS design with square air gaps (parallel walls). There are slight differences between the two final prints, but have no clue (yet) which one could be the better? By now it seems that printed with the same dimensions, the SQ version is a little more loose then the AN.
So far I've just tested the pieces by hand, they work pretty good. I observed an interesting flaw or feature (?) on the AN test piece, printed in PLA: if I leave it alone for a while, it is like "stick" on the rod, but if I start to move it, after a couple of movement this stickness goes away and it is sliding perfectly, without any play! Kind of self-healing? :D I'll see once they will be in actual use how this issue(?) will progress.
Regarding material, I've printed them in PLA and it seems good for now. Maybe I can try to get some filament from IGUS and try that material later on.
Chinese noname PLA