Cast iron grate repair

Greetings Terry, I'm not sure which of the rods mentioned above is best for your job but I do know that there is a rod available for stick welding cast iron alone or welding it to steel. I used the stuff years ago and it worked very well and I think I bought it at the hardware store.I think it was the Ni-55. In fact, I'm almost positive that's what it was. Your idea about pre-heating is a good one. When I weld cast iron I use ceramic blanket material that I buy from Seattle pottery supply. I like the stuff because it is real easy to make a form fitting oven. When I use it I lay it on the welding table, lay the part on the stuff, and I pack it around the part as close as possible. If the part is heavy I will lay fire brick on top of the blanketand lay the part on the fire brick. I then use a weed burner to heat the cast iron so that it is very hot. Then welding commences and as soon as I am finished welding I cover the part with the blanket to cool slowly. Since I started using this method I have not had any parts with cracks once cooled. A couple jobs I have done had such thin cross sections being welded I worried about strength after welding. So I welded some mild steel reinforcements to the cast iron. Eric

have

I do not have much experience welding cast iron. But read

It only mentions peening when you do not preheat. When you do not preheat , the weld shrinks on cooling and the cast iron does not. So you peen the weld to make it expand. I think the NI-55 shrinks less than NI-99. and m ay have about the same thermal expansion as cast iron. I am just guessing here. ( invar36 is 36 % nickel. Invar -41 is 41 % Ni. INvar 36 has less thermal exponsion acound room temperatures , but invar 41 has less thermal expansion at higher tempertures. ) But Ni-99 is softer and will yield .

I would probably go with NI-55 as it is a lot cheaper than NI-99. But if y ou preheat you could probably use CI rod.

Dan

Dan

I wandered around the internet and found a site ( welding tricks ...jody ) that mentioned using 312 stainless rod on cast iron.

I am pretty sure that I have some invar 36 and invar 41 tig rod and could cut some to fit in a flat rate box. But as I remember it is all 1/16 dia. Let me know if you want some.

Dan

I know what a pain these kind of jobs can be and I wish you luck! I would truly like to see a before and after and explain your process.

$499 Annie (OOS, but the parts are in) $741 Roy

See 'web store' button on fluxeon page.

Gonna buy two? They're small.

Propane torch and a pan of water ?

Don't forget the lazy susan base.