770 Welding Rod for Cast Iron is excellent for welding in deep recesses or on non-conductive coating. Creates very strong joints on cast & steel applications. Excellent for many different applications : Pump bodies, Compressors, Machine frames, Casting defects, Lathes, Pulleys, Dies, Levers, Gears, Generators, Flanges, Tables and engine blocks. Weldingrods.com 770 Cast iron is fully machinable and has a tensile strength of up to 55,000psi.