SOme cast Iron and some stainless

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A week ago I was asking about stripping NI99 stick rod and using it to weld cast iron with TIG. Well, I tried it and it works great! 1" stringers, let each one cool completely before doing another. No preheat. No postheat. No signs of cracking. Actually, when welding the pipe on, if I didn't add much filler to the end of that particular stringer, and didn't "crater out" I could "make" it crack, but overall it is extremely forgiving. I wanted to weld a pipe onto a cast iron turbo manifold to add an external wastegate, to make things more difficult this manifold has some cracks that went right through: Here is an example: So, die grinder with a carbide burr abd "vee" them out:     Then we weld them using using TIG. I am using a 3/32" pure nickel rod (NI99) and around 120 amps I guess. No preheat. No postheat. I ran 1" of weld, and allowed it to cool naturally until it was cool to the touch. Time consuming but I just work on other stuff while it cools.  So I ran the one pass straight in the VEE, basically a root pass. Once that was done I did a bdit of grinding here and there as there was a bit of porosity in a couple of spots.  Then I ran a weave/cap at around 100amps:    I ran that over all of the cracks as well.   As far as the NI99 goes- it runs OK. Welding cast iron is weird, it's kinda... "lumpy". It's a good quality casting though from what I can tell.  I noticed I have no decent pics of where I welded the pipe to the manifold, or the hole in the manifold itself becuase I guess I am a tool. I'll take some tonight. Here is one weird pic of the hole machined in the header and  where I laid some nickel filler around the edge, run fairly cold just to kind prep the material.  Then I burned the pipe onto the hole:   Here is the one pic I found of welding the pipe to the manifold, this was dfone in 2 passes as well, this is just the first one (nickel rod still- notice this is welded to cast and shows no sign of any crackinf at the end of the weld):    I used schedule 40 steel pipe for this, rather than the sched 10 stainless I was originally planning on. It's a long piece of pipe with quite a bit of load on it so I decided that thickwall would be better.  The pipe needs a LOT of cleaning to weld very well with TIG- it seemed to have a lot of oil on/in it. Plus I am certainly no pipe welder!!! Anyways I welded the pipe in 2 passes- one root pass at around 130amps with almost no filler then a cap at aroun 80-100 amps, here you can see the root pass with the cap going on top:  Finished weld, a little hot/undercut, etc but it'll do:   Here is a pic of the inside, you can see at the bottom where I got a little hot an almost dropped through. Overall, fairly decent underside, good solid 100% penetration right through:     And here's a horrible pic what it'll look like, I have to just weld the pipe onto the "stub" piece of pipe I welded to the manifold, I'll take better pics tonight:   Anyways all in all the nickel rod+ stronger works good! I had no cracking issues at all.
Reply:A couple from the latest header round:      More tonight.  :cheers:
Reply:Looks good to me... Like the header!
Reply:Good job!But i must say... i once visited a welding rod fabrication shop and learned that the base metal of the rod is almost if not always the same. The only thing that makes a rod a 7018 or a NI99 is the composition (ingredients) of the flux covering the rod.I might be wrong here, but that's what the folks at http://www.soudotec.com/englishpages/indexen.html (that's the shop i visited) told me...I'm open for comments and clarifications from your side!Lincoln Ranger 250Lincoln LN-25 Across-The-Arc FeederMobile Unit / Workshop (drill press, air, welding, horiz bandsaw...)[SIGPIC][/SIGPIC]
Reply:hmmm... i just tought about it..... i guess for nickel rod it might be different since the base metal probably has to be nickel... ho well. i'll investigate that furthermore!Lincoln Ranger 250Lincoln LN-25 Across-The-Arc FeederMobile Unit / Workshop (drill press, air, welding, horiz bandsaw...)[SIGPIC][/SIGPIC]
Reply:Originally Posted by bordenGood job!But i must say... i once visited a welding rod fabrication shop and learned that the base metal of the rod is almost if not always the same. The only thing that makes a rod a 7018 or a NI99 is the composition (ingredients) of the flux covering the rod.I might be wrong here, but that's what the folks at http://www.soudotec.com/englishpages/indexen.html (that's the shop i visited) told me...I'm open for comments and clarifications from your side!
Reply:Originally Posted by CapnbondoDefinitely not. If you buy a stainless welding rod, the actual metal inside the flux is indeed stainless steel, an aluminum rod is aluminum, and so on. Nickel welding rod is not mild steel rod with different flux on it, that just wouldn't make sense.