Thread: TIG welding cast iron ???

G'day Fellas,
I had a mate from work ask me if I could do a repair job on a couple of broken cast iron pieces for him. One was a cast iron leg from a small BBQ and the other was the ACME thread insert from a vice which I think may have been cast steel.

I had intended to bronze the BBQ leg and use Castcraft 100 stick electrodes to fix the vice insert but on the spur of the moment, I thought I would try using TIG with 1.5mm 316L stainless filler rod, my logic being that stainless filler contains nickel.

First I welded the cast iron BBQ leg, the broken section was about 4mm thick so I set up at 60A using a ceriated electrode with pure argon and low and behold it welded up a treat.
On to the vice insert I upped the current to 80A and after chanfering all around the break to allow for some build up welded it, again it worked beautifuly.

Both welds seemed strong with good penetration and flow and unlike braizing or using cast iron electrodes, the base metal melted and fused with the filler. I would have liked to test them to destruction to see how strong they really were but my mate may not have liked that . He is using his vice again though and all seems to be working well, and a vice applies a fair load, enough to break the insert in the first place, of course it is a Chinese vice.

I have not heard of TIG being used to weld cast before and was just wondering if this is a normal practice or if anyone else has had a similar experience?
Cheers,
Greg.

Thats a new one on me, but a fascinating idea. I have long hated trying to repair bronze.