If you want to see my best projects, I invite you here: 

https://cults3d.com/en/users/Guliwer06/3d-models

It is a Vw Golf 4 wheel cap.
Diameter = 55mm

3D printing settings

Supports = don't need
Rafts = don't need
Brim = don't need
Infill = 15%
Resolution = 0.2