Welding for a Planishing hammer

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I'm using a air hammer to make a planishing hammer. I need to arc weld the air chisel to a steel bushing. I think the chisel is cast steel, with the outside chance of it being cast iron. If it's cast iron, I've heard that Super 40-60 is the best rod to use. If it's cast steel, then would something like 7018 work or would something like 6011 be a better choice of rod?
Reply:I'd be a bit worried about welding the chisel being as how it's pretty hard steel (could well crack). Have you checked around for air chisel attachments that have a round head on them that'd work for planishing instead? Might even check with a planishing machine manufacturer and see if you can buy just the tooling for cheap.
Reply:I haven't found anything at the width needed for the hammer in a stock chisel. 1 guys says to silver solder the chisel to the head, and another says to braze it. I'm just wondering about welding. Since I'll need to heat temper the head. I thought welding would be a better choose. I would pre heat the pieces and then weld them together. Since I'm new to welding, I'm asking as many different people as possible.
Reply:When I initially read this post I thought brazing was the way to go.  If the fit is really tight (no noticable play), then use silver brazing alloy.
Reply:Ive seen planishing hammers made from air hammers that were simply clamped on and the trigger held open with a zip tie.Check the picture  section there should be a pic of one in there
Reply:Actually, you can buy air chisel bits that are a straight rod with the lip for the spring retainer. If you know anyone with a lathe, I'd have them turn the mushroom-head end and have the convex side turned so it has a hollow tube sticking up that fits the air chisel bit (one piece turning). Slide it on and use a couple stought allen head grub screws with some blue/red loctite. If you know what a mushroom-head valve lifter from an engine looks like (older VW's use them) that'll give you an idea sort of what I'm talking about.
Reply:if it were me i would tig weld it with a soft s/s steel rod, probably 308 and see if it held up, if you dont have a tig and you dont want to buy anything, try 308 s/s stick rod, what do you have to lose.There are muti alloy rods out there
Reply:I've never seen just a straight chisel rod and the largest flat heads I've seen was .75". I'll be using a 1.5 to 2" head on the hammer. I don't have access to a lathe so that's out. Figure just basic hand tools and a drill press for the fab. I have access to any type of welder I would need through my welding school. But if I braze or Silver solder, I’ll have to re-do which ever after I heat-treat the head and that could effect the tempering.