Mayhem, yes I could add more height with an extension, and yes the idea was to use charcoal made here. We'll just have to wait and see. I could also go waste oil crucible, etc. But my real hope was for a single charge charcoal melter, either cupola or crucible.
Toward the end they broach the furnace shell and refractory with a bar, leaving the blast on which they deflect with a shovel, then drive a pipe in through, and duct tape a second blower on.
Awemawson, that video was absorbing to watch on the other side of a computer screen, but not live, not my cup of tea in just about every way. Great gobs of bot, patted by hand into place, broaching walls with the blast on, a tangle of inexperienced helpers, and a bunch of spectators is not quite how I imagine wanting to work with iron. Concentration is more admirable than heedless showmanship.