Hi Brian,

The hat band was just a Profile I made with the "creases" in it.
I then did a Sweep, with one of the rails being a deformed curve to get that higher & lower effect.
Again, it was one of those things that took a while, just trying different curves & adjusting the various Points where needed.

Bear in mind that most of the hat's pieces haven't been Boolean together.
That's because I was designing it for machining, not for any rendering.
Mind you I have no experience with Rendering, so I'm not even sure if this model would be suitable for it or not?
Rendering is something I'd like to learn & understand, but at this point I'm concentrating on the modeling side of things first.
I'm figuring there's no point in knowing how to do a Render if you can't produce the model first?
Not sure if that's the right way to look at it or not, but figure I'm better to learn to crawl before I try running!

regards Colin