SciTubeHD | Melting Steel in Open Air with Homemade Induction Heater @BrianDhvTinkerer | Uploaded October 2022 | Updated October 2024, 1 hour ago.
An easy to build device chech here for build instructions for a bigger unit:

teslascience.wordpress.com/autotuning-9kw-induction-forge-version-1-2

In order to enable current protection for this device, please check here,:
 teslascience.wordpress.com/simple-and-effective-induction-heater-current-control-circuit