My bucket is rusted out in many places. I need to replace the sides and part of the curved portion. Do I need to use a 7018 or can I just use my mig to weld the new metal in?
Standard welding wire like ER70S-6 is the equivalent of 7018, if you do proper welds with proper prep and depending on the material, preheating, you should be fine. The 70 means 70,000 psi tensile strength.