I've found that with the 2kg (~4 pounds?) spools the regular filament holder of my ender 3 failed significantly because of the weight on the frame and the amount of friction between the spool and the rod it should slide on. Because of that, I've come up with this design - a simple two-legged spool holder utilizing two 7x22mm ball bearings. Simply hammer them inside the main rod and then push the roll ends inside. Tall enough to fit a 2kg spool (although I guess you could put some books under each leg and it would work for larger spools as well)

Creality

Ender 3

No

No

0,3mm

20%

Designed so that it can be printed without supports. Had to print the legs diagonally since they wouldn't fit otherwise on my ender's bed.