I like my screws well tightened to avoid vibrations and noises, but those layer fans are so fragile, just a bit of too much force will split the screw hole.
I tried fixing them with glue, but they keep splitting again as soon as I re-tighten them.
So I designed a protective cap that keeps the split sides together and allows me to screw my fan to my heart's content.
It uses just 0.12 meters of filament per piece, with a brim added because it has a quite low profile (0.1 m without it).
The author hasn't provided the model origin yet.