Originally Posted by MoparFreak69
This statement couldnt be more WRONG. Cast STEEL is very easily welded and will provide a very safe weld when welded with sufficent heat. You are thinking of cast IRON which is very brittle and cannot be welded easily and if done improperly will be quite unsafe. I wouldn't hesitate to cut and weld on a cast steel part, I am however an experienced welder and I know what it takes to get a properly penetrated weld with the strength required for the stresses the part will be placed under. Ask any old time farmer the difference. They will know the whats and hows.
^^^^ x2 on this.
BTW it really bugs me how people can't tell the difference between forged and cast parts. There are so many myths out there about fabrication. Its easy to tell - just by looking at the part. Mine are forged on my D30 - I just went and checked. Look close at the "parting line". This is where the 2 halves of the mold came together on a cast part, on a forged part its where the 2 halves of the forging dies came together. I fine thin line is cast. A wider line (say about 1/4") is forged. Usually a forged part also shows grinding marks where they cleaned off the extra flashing. You also have to use some freakin common sense here, people! Highly stressed parts such as steering and engine connecting rods are almost *always* forged, for strength.
I wouldn't weld a knuckle that is going to be driven on the road unless I did it very carefully. And like MoparFreak69 says, I actually *do
* have 20 yrs experience plus trade school and certification. IMHO the knuckle would have to be annealed and heat-treated afterwards, and then completely re-machined. This will lessen the chances of cracking due to different properties of wrought vs cast and having to deal with the grain of the steel enlarging. This requires a industrial controlled oven and machine shop, etc... prolly at about 1100 F for a few hours. I actually could do this at work but certainly not at home. Definitely use low-hydrogen or MIG or TIG and be generous on the heat and bevel the edges.