TIG welding 304 stainless headers with 316?

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I am working on a set of exhaust headers in 304 stainless. 308 filler is basically non-existent here in anything under 1/16. I am therefore left with two options with the first being weld the 304 with 316 filler (available in .045) or endure the wait that is international shipping for some 308 filler to arrive. Am I likely to experience potential weld cracking or any other nasties by welding 304 with 316? The application is for a supercharged engine with relatively high (not turbo) EGT.
Reply:Look at filler on spools for MIG welding.  Under 1/16, it's easier to find in wire.
Reply:The weld will be just fine welding 304 material with 316 filler.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:Originally Posted by rlitmanLook at filler on spools for MIG welding.  Under 1/16, it's easier to find in wire.
Reply:308 is the lowest grade filler metal that  you can use for 304 Stainless work. If you were welding stainless to mild steel you would need 309. Its an acceptable practice to use filler rod graded higher than required minimum, which in your case will be 308.You should have no problems with the 316 working as snoeproe stated.Good Luck!!
Reply:I use 316 filler for all my stainless tig welding.It takes a lot to crack a stainless tig weld. Stainless bends very easily without cracking.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:There is no problem using 316 filler to weld 304.  To make a steel "stainless" it needs to contain a minimum of 12% Chromium (Cr). The Cr oxidizes in the atmosphere forming a passive layer on the surface. This layer, unlike coated steels, is self repairing should it be scratched.The problem with 12% Cr is that it is fairly brittle and only provides the minimum corrosion resistance. Increasing the Chromium content to 17% improves corrosion resistance but increases brittleness. Adding 8% Nickel makes the steel ductile again. Thus 18/8 stainless was born (304). 316 / 316L has additional Molybdenum and higher Nickel which provides greater corrosion resistance. 316L is 19%Cr, 12%Ni and 3%Mo.  308L is 20%Cr and 10%Ni.  Both have higher Cr and Ni content than 304, so a weld using either filler will have a higher alloy content than the base metal ... the exact concentration will depend on the amount of filler added more than the selection of which filler you use.Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:Originally Posted by 4sfedThere is no problem using 316 filler to weld 304.  To make a steel "stainless" it needs to contain a minimum of 12% Chromium (Cr). The Cr oxidizes in the atmosphere forming a passive layer on the surface. This layer, unlike coated steels, is self repairing should it be scratched.The problem with 12% Cr is that it is fairly brittle and only provides the minimum corrosion resistance. Increasing the Chromium content to 17% improves corrosion resistance but increases brittleness. Adding 8% Nickel makes the steel ductile again. Thus 18/8 stainless was born (304). 316 / 316L has additional Molybdenum and higher Nickel which provides greater corrosion resistance. 316L is 19%Cr, 12%Ni and 3%Mo.  308L is 20%Cr and 10%Ni.  Both have higher Cr and Ni content than 304, so a weld using either filler will have a higher alloy content than the base metal ... the exact concentration will depend on the amount of filler added more than the selection of which filler you use.