A spool holder I drew up following the anet spool holder that came with one of my printers.
this will hold a 1kg spool of 1.75 or a spool of the 2.85 filament. I used 2 m5 x 30 mm bolts on the roller they they thread in fine but leave about 8mm sticking out so they will slide into the slots and hold the spool.
this will need a print area minimum x 200 y 200 z 160

Anet

A8

No

No

0.16

10