TIG vs. cast iron

Try looking on google first, so that you can refine your question once you have learned what you can from the archives.

This topic comes up very frequently in this forum.

Look here:

You can also get nickel rods to weld it up with the stick function.

Cheers-Jeff

V-grind the crack.

Preheat to about 500-700 deg F (a drop of motor oil will flash off at 650 degF)

TIG weld using pure Nickel rod in short sticthes, peaning the stitches as they cool.

Slow cool by burying in powdered lime or vermiculite (both available at garden supply stores for cheap)

What needs welding on the brake drum, and why? I'd be generally inclined NOT to even consider welding or brazing a brake drum on any vehicle that can exceed 10 mph or does not have dual brake circuits.

Are you giving the brake drum a new home, like in making it into a shop-light stand? If so, just weld it up like you would mild steel.