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kibwen

That's an incredible application of induction heating that I hadn't considered. How big was the coil?

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Induction forge.

https://youtu.be/P_STrnP__D4

Kind of wild to watch him hold the rod with his bare hands while it gets red hot.

Steel is a poor conductor of heat. You cannot do this with aluminum or copper.

You can’t do it with aluminium or copper at all. There will be no heat to conduct, so hold it as long as you like.

A myth. Copper and aluminium won't heat on a consumer-grade kitchen induction stove, which only have a set of coils designed for ferrous metals, but restaurant kitchen professional IH stoves can use the different frequencies that heat non-ferrous metals, and a forge or melting furnace can indeed melt any metal, ferrous or not.

Why don't residential induction stoves have that capacity? Given the popularity of aluminum and copper cookware I'd think it would be pushed out. It's one thing people always bring up with induction ranges.

The electronics to drive the right frequency for efficiently heating ferrous metals (about 25KHz) are affordable. The electronics to drive the much higher (at least double?) frequencies for non-ferrous metals safely are not so affordable. It would add more to the cost than a new set of cookware. Cast iron is the king of cookware and works great on IH, anyway!

You can put a few mm thick piece of steel on top of the hob and then set your copper pan on that, as a workaround.

This is incorrect. The magnetic flux will induce an electromotive force that will cause a current to flow in any conducting material and cause heating if this material is not superconducting.

As an example, induction heating is a commonly used method in zone melting for Si-purification [0].

The effect is more pronounced in ferromagnetic materials because a larger flux is induced.

[0]: https://en.wikipedia.org/wiki/Zone_melting

False, and I have the scars to prove it.

You can even do induction hardening. Used for complex parts, of if you want hardening with a very well defined penetration depth.

The place I used to go had a gas furnace to heat the metal. A pitty I didn't find time to go there for ages now... Only downside of gas furnace, closed on on end, is the limited length of the stuff you can put in. I have an idea I want to try to forge longer things, but again, it is months now I didn't have time to get back to it...

You just have to put a door on the back of the forge. Or block the back opening with a firebrick.

Yeah, but it is not mine! Also, there is a open gas forge sitting right next to it. So, the place decided if some work and investment is done, it will be on the open forge. Which I can only support!

But yeah, I just realized the last time I was there was last year before christmas... Good thing anout this is: the day I retire I will definitely not be bored at all!

Maybe 6 inch diameter.

Ah, my bad - looking at induction forge images and links in this thread, the coil was probably closer to 3 or 4 inch diameter.

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