:My buddy fro 42 draft designs had to weld this with a Back pressure of Argon of roughly 7cfm and 170 amps of power!! :Once over to fuze, then back over with filler.. :Got very hot, had to pause halfway through and let it cool down, It took roughly 3 Hours total to get it to the completed point. :I cant wait to get the whole manifold done!! Still need to fab it up. : : :-George