cast iron repair ?

Wow, that sucks. Yes after welding, you will need to resurface it. I have seen videos online for a process called muggyweld. They have different rods for different materials. I believe in one of the vids they welded a plate over a hole in a cast iron tractor block where a connecting rod let go. The part has to be notched out where the weld goes. I think they pre heat it and use a torch with mapp gas to feed the muggyweld rod in.

I dunno what you payed for em but I was kinda thinking of going this direction in pic below and just buy new ones since I dont need casting numbers and date codes, plus unless the seller is honest, and you can inspect them personally it's kinda a crapshoot.

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