I welded them back together when I got the machine and they have broken right beside my welds, I kept hearing tink tink tinking while I was welding and suspect it to be cast iron. is there supposed to be some 3/4 plate or rubber bolted to the bottom that I am missing? I am thinking about bolting 4' thick oak to it after this fix cycle.
The pads definitely look like cast, but they would most likely be cast steel not cast iron, and cast steel is generally weldable if you use the right procedures. That tink, tink, tink you were hearing was the pad cracking under the stress of the welding contracting as it cooled. Did you pre-heat the pad to a couple hundred degrees with a torch before hitting it with a welding electrode..?
yep, good clean base. good preheat. and my welds cracking right down the middle. I looked it up on google and I think it is high carbon steel causing hydrogen cracking of my 7018 weld. the solution for me was using 309 welding rod. so now it's welded back together but I need to put some wood on the bottom of it.
I don't know Cats, but on a backhoe there would typically be rubber "street pads" bolted to the bottom of those. Or they'd have steel cleats to dig into the ground. If you don't need the rubber, then I'd cut a plate to fit and weld some angle iron to it, then bolt to your cast pieces to take some of the load.