Filament Thrust Bearing

Is it really necessary to mount filament spools vertically? Vertically obviously has the least chance for gravity to mess around and entangle layers on the spool. But let's see...

This is a thrust bearing for mounting a spool horizontally. It centers spools with a 19mm, 32mm or 52mm hole perfectly. Or any other if you don't mind that it moves a bit sideways..

To better fix spools on the center pin, some caps are available. Basically a cone centers the upper side of the spool. There is a sh