SLIDE WARNING:
I was going to make one out of fire bricks like we used in our fire place, but could not find any in stock anywhere.
I did make one out of concrete blocks, but they aren’t really safety approved for use with fire, so we didn’t use it. Instead, I took it apart and used it to build a raised garden bed.
Catching up on some replies...
Agree, the concrete block isnt best as it starts to split and crumble from the heat. Metal rocket stoves are better. BUT i had extra blocks laying around, and a crap-load of yard debris...