Most of your hardware store small steel is mild steel. Don't worry about it. As far as welding stainless to carbon steel you need a 309 stainless arc welding rod the standard is a 308 and it would probably work ok but for ultimate crack resistance on dis similar metal like that the 309 is recommended. For the small amount you are dealing with I would bolt it together with stainless bolts or screws. For one thing the stainless will get color marks, blue and straw colors from the heat and who wants to get a bottle of tri gas for that little bit. I would use the straight wire mig with the c25 gas you got over the flux core simply cause it's cleaner and nicer with less spatter unless you are outside in the wind although either will work. If it's magnetic and you can bend it center punch it and drill it without breaking your punch or burning up six drill bits on a hole its mild. The good stuff is like a570 or ht1 or hy80 and you aint getting that at home depot and if you did you would pay dearly for it. It is also weldable but much harder to center punch and drill cause it has more carbon in it so its tougher stuff. Just sort of figure that if it isn't a tool its mild.Thanks for the info. I got already made foot pegs that fold up, so I will maybe use the stainless steel pieces if I find some other use for them later.
Safety I have been told about having footpegs that foldup if they hit the ground for some reason. I may even make the square tube that was going to support the foot pegs further out to clear my chain and carb covers angle up a few inches higher. This will allow more of a lean in a turn and the pegs less close to hitting a rock or a bump when off roading as it is meant to be used for.
Just one other question, I bought the steel at OSH and they just say that it is weld-able. What more does anyone know about this stuff. I Tig welded it and now only have Mig available with flux core or the AR 75 C02 25 shield gas to use. Would you suspect that this is mild steel, maybe I can contact the store and find out the supplier they use to get more detail? I also may have got some at HomeDepot as well, so I am curious to what is it's make up?
Measure Twice
Didja know you can make your own tig welder with a 70 amp automobile alternator and a 5 HP motor? Can probably get away using a smaller motor if you don't plan to do anything too thick.