After first acquiring my Ender 3s, I realized the included reel (spool) holder wouldn't work - reels had to overcome too much friction to turn on its hub, which would not rotate. I then purchased the Creality rotatable spool upgrade kit (see below link), which did work better, but I didn't like how the reel sat on the holder's hub; there was much less friction, but the reel's hole was about three times larger than the holder's hub diameter.

Like so many others, I searched for solutions to print - and purchase, but was not happy with the many, many options out there - fit or function. The available options looked fit for purpose, but their function is yet to be effective for my taste, especially for some of the more elaborate designs.

I designed a three-piece solution (two shoulder flanges - print the respective flange twice, one bushing), and remembered each company usually has a different sized reel, so make two kits - Sunlu reels & Hatchbox reels); so far, they have worked without problem. The ID's of both the bushings and shoulder flanges were reduced by 0.5mm to allow for subtle variances in reels, but still have a solid feeling fit on the hub; the OD of the bushing is the same 0.5mm smaller than the ID of the center reels. There are no special instructions for printing these, other than the typical ensure the bed is as level as possible, set Z offset and use dry PLA.

I had to buy a small bag of thumb screws to take the place of the Allen head bolt which holds the hubs end cap on, allowing for quick and easy filament reel changes; the link to them is below.

Note: Do not intermix the Sunlu and Hatchbox bushings and shoulder flanges, each company's reels are different sizes, which is why I made them in kits.

Good luck.

Creality Rotatable Filament Spool Holder Upgrade Kit: URL: https://a.co/d/cWuTt2q

Knurled Thumb Screws (M4 x 10mm): URL: https://a.co/d/4R1U1Yh