This is the first model I've done for 3d printing, in the next time I will create several models.
The Model does not need any support structures.
I tested it only with a resolution of 0.12mm, and a size up to 140%.
If you make the tower bigger, or if you use a larger layer height, this can lead to dirty edges.
I am a hobby 3d Artist since 2004, I will regularly design new models for 3d printing.