Previous casting attempts have used a commercial 26 kw blow torch, but I found the air intakes were too close to the foundry chamber so the torch tended to suck reflected combustion gases back into itself and hence starving itself of oxygen. This is an experiment to try making my own naturally aspirated burner with a bit more distance between the reflected flames and the air intakes. Operating pressure is about 3 to 4 bar. Metal working equipment is primarily a Warco 250 lathe, and WM16 mill. CAD work is in fusion 360. The burner design is based on the book 'Gas Burners for Forges, Furnaces, and Kilns' by Michael Porter. As ever, try this at your own risk and I make no statement to the safety or operation of the design shown.