Same. Magnetization current and core saturation are fairly fundamental properties influencing transformer design, but they're barely even mentioned in introductory texts.

I feel like a lot of modern transformers are just sort of cargo-cult imports of old designs because everyone who knew the salient parameters has retired and the current crew just kinda nudges things until they work. A from-scratch explanation, up to the current state of the art, would be invaluable to anyone who deals with them.

But nah. This is HN, where headlines are their own code.

In that case you might enjoy this:

https://ludens.cl/paradise/turbine/turbine.html

Was posted here a while back. Fascinating guy.

I thought it would be about making a Transformers like toy using 3D printing or something.

That would be a really neat project: printing a functional transformer as a single piece.

Same here, would have loved a build creating some actual transformers :)

We did in school on a coil winding machine, and also learned the math.

I don't rember the winding part being that much fun. :)

It was something old, akin to this: https://www.youtube.com/watch?v=Y-GyMYZ8yTU

RF transformers (in forms of various coils, chokes, baluns, etc) are more interesting and complex to analyze. I once winded three of them, and none worked. I thought I finally found an article that explains the subject, well, not a chance ;-)

I was hoping for monad transformers.