MIG Welding Aluminium

since i cant TIG under 3mm alloy and i have half a sheet of 1.6mm left i was wondering if i could use a MIG welder suitable for alloy welding to "spot weld" instead of running a full welded bead and blowing holes to join my panels? i dont know what this type of welding is called but u push the button to do a spot weld and than repeat along the whole weld so it looks kind of like a tig weld



im thinking of welding a aluminium fuel tank and live bait tank for a boat im building also was thinking of welding together a couple tuna tubes