Five years ago I pulled a Power Puff plastic top out of a box of cereal. Having no children, I gave it to a particular coworker who had kids "the right age".
When he saw the toy, he was reminded of some wooden tops that he had watched kids play with in Chile several years earlier. He said they were called "trompos". One thing led to another, and he received the following images from someone he had known in Chile:
He also received the following diagram:
This all looked very interesting to me, so I cut out a copy of the trompo diagram and took it to the lathe. This was my first attempt, from a piece of cedar:
The grooves were obviously too deep (and too square-bottomed) but my coworker got it to spin just fine. I gave the trompo to him as a gift, and made a few more.
Trompo #2 was made of apple.
It had some problems at first ... the string kept sliding right off the pointy end. This was because:
1) I made it too smooth, and
2) I hadn't provided a good groove to anchor the string into, so it could be wrapped over itself.
After I roughed it up a bit, this trompo became my best spinner:
The vertical grooves that I carved didn't have much of an effect, but the circular groove near the tip did. If I remember correctly, I also ground the nail down a bit to stiffen it up and reduce internal vibrations.
Trompo #3 was made from ash. Its smaller size made it a little too lightweight to compete with #2.
Trompo #4 was a little too bulbous and top-heavy. It was pretty much a non-starter. I'm not sure if I want to show pictures of it or not. Oh, what the heck....
Starting to wind up a trompo:
Trompo ready to go:
I use an underhand throwing position, but I have heard of both overarm and sidearm positions as well.