Thanks... Yes I figured it would be rather involved, exact pre heat and anneal is not too much of a problem as I do have a decent heat treat oven, and I kind of expected as much... And i am even considered welding in a purged environment... I need to do some research it sounds like. I knew about the availability of the 309 filler and other 300 series rods,but hadnt seen the 420 rod, and yes I will have instances in which the weld area is more cosmetic, where corrosion resistance is more of the concern but in those cases the 309 will probably fly, however some will be heat treated but not welded on critically hardened areas, but dealing with stress risers and other potential problems are going to be fun to figure out just what I can get away with without getting into trouble.... Oh well thanks again, I am a little ways away from really needing to pull that rabbit out of the hat, but i have some design ideas that will require it and it was just on my mind and thought I would ask...