DIYed from a discarded empty Helium tank, with a homebrew insulating refractory* liner, and a salvaged broken hair dryer/ dimmer air flow control to keep the fire reductive as not to enter unnecessary gas into the melt. "Crucible" from a chopped-off Helium flask. 12 quid in total material costs, and app 4 hrs of work. £ 1 worth of charcoal briquettes and 1,3 kg of (free) Aluminium junk gives after 20 minutes of burning/degassing & fluxing half a litre of excellent molten Al alloy to cast. * Perlite insulator, silicon sand filler and waterglass binder.