TL;DR: normal sand casting, using a microwave to heat up the metal inside an insulated silicon carbide crucible.
It's not, like, using the microwave to sinter a metal-powder 3D print or anything special like that.
this post was submitted on 26 Mar 2026
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I didn't know silicon carbide heated up in the microwave. I learned something from the article.
People often make rubies in microwaves. Microwave crucibles can get exceptionally hot.
I started watching the video on Youtube, but almost immediately switched to an older video from the same guy that went into more detail on the metal-melting part.
It's been popular for making ceramics at home in microwaves for years
...And also breaks instantly as soon as it's put under load. The process is for sure very interesting, but a simple casting like this is not the correct method for making something like a wrench. It'd be useful for plenty of other parts, though.
Yeah I'd much rather buy a wrench. Making a unique replacement part perhaps would be a better use example.
Well, it will work... until it suddenly doesn't.