3/32 or 1/8"
Drill (rpm and feed) slower than steel with cast iron and that small of drill dia. or you may break the drill off.

Vee out the groove (both sides if you can) wherever you weld it and don't forget the small hole at the end of the crack.
A gas grill will work to preheat and control post heat if you have one.
I'd clean the paint back also to minimize contamination in the HAZ (heat affected zone)

Yes

Have had one since 1997. Good for light work - stick and tig. including aluminum and SS. It does not have ac balance, or pulse but has worked flawlessly since new including yesterday. 1 thing that they don't tell you is if the tig arc doesn't start when pushing on the pedal then touch the tungston o...