For my machine I have filament spool standing on the floor, under the desk. I discovered that during printing filament has a contact with printer's upper corner. Simplest solution was to add some sort of guide. In my drawer I had spare 6001 bearing (28x12x8), some M8 washers and M6 screw.So I designed holder and reduction sleeve (12mm external diameter and 6mm internal hole)It's for MendelMax 1.5