(pic#1 and 2) 1" untested pipe. U can use black pipe but it's thinner and does not stand up to the heat and will rust and flake. Thread and cap end.
(pic#3 and 4) gas mixer is a 1" cap about $1.50. Drill (4) 1/4 inch holes on face of the cap and drill and tap the center for a 1/8 inch npt thread
Purchase a high pressure regulator. Heres one from agri supply
PRESSURE REGULATOR 360#189 ADJ. W/EXFLOW POLY 36" HIGH PRESSURE HOSE
pic of hose end hpim0063.jpg
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