When using filler metal you want to use soething as close to the base as possible. If it is a part to be heat treated you can get ER4130 filler. Other wise a mild steel filler like ER70S2 will pick up enough of the alloying elements to create a weldment of equal quality.
1.What kind of wire would one use when mig welding cromoly?
2.Is the rust rate of the mig bead going to be greater than the rust rate of the cromoly tubing?
3. Is there a disadvantage to mig welding cromoly rather than tig welding it?
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