Welding Tips and Tricks

Hey Guys I have a job today to weld some cast iron and jut wanted to know what filler rods I can use? In the past I stick welded any cast, but I want to Try TIGing it. Is it possible to use Stainless filler on it? Also I think I may have a stick rod there I guess I could brake the flux coating off it and use it right? Thanks

Short of a high-Ni rod like Hastelloy W, I've gotten decent results using 309 rod.

If you have a good high-nickel stick-rod, you can bust the flux off and TIG with it. A regular 60- or 70- series rod won't do as well as 309, though (in my experience-- others' results may vary).

A good preheat and a slow cool-down will help, too.

Good luck, cast is a strange animal. If it cracks along the weld, all is not lost; often a dressing and re-weld will not crack out a second time.

Steve S.

I've repaired cast iron engine heads and exhaust manifolds with 'old piston rings' for filler. They have a high enough nickel content. I preheat the part in the BBQ as hot as I can get it, then when I am done the weld, I post heat it in the BBQ while gradually lowering the temperature. It might not be the most approved method of welding cast iron, but it works in a pinch, when nothing else is available.

I hadn't thought of piston rings for a high-nickel filler!

That's a keeper!

Steve S.

Steve, there are a lot of things out there that people don't know.
For instance, the metal used for making rifle barrels is hard to get.
Not so hard if you know that axle shafts are made of the exact same metal.
Sometimes, the material that you are looking for, is right under your nose.

I often find information in the strangest places. http://www.scribd.com/
Type a 'Keyword' or topic of interest at the top of the page and press 'Search'.

Otto Nobedder wrote:I hadn't thought of piston rings for a high-nickel filler!

That's a keeper!

Steve S.

I never had to weld cast iron, but I hear alot of peolple also have good results with sil-bro for tig welding cast iron. I hope that may help some

Silicon-Bronze is a good choice, but it's not welding-- It's brazing.

It can be done with TIG, but the service will determine if it's suitable for the job. I didn't ask, so it might be a good alternative for him.

Good thinking.

Steve S.

My favorite 'Gas' torch is the Henrob 2000. Check out the video on 'Cast Iron' welding.
http://www.cut-like-plasma.com/info_wel ... t_iron.htm
Cast Iron has a lot of thermal stresses and TIG is such a precise, pinpoint heat source.
The reason that I like 'Gas' welding cast iron, is that it's easier to preheat and post heat.

Thanks for all the info guys all good! Cheers.

I worked with a guy that welding a lot of cast iron parts and used Vermiculite as a post welding heat treating. It slows the cooling down drastically. He had said that you'd put the part in the Vermiculite and leave for the night, come in the next morning and the part was still too hot to handle. I've never personally used it but if I get a cast iron job I'll be looking into it.

http://en.wikipedia.org/wiki/Vermiculite

That is a fantastic tip. Thank you for that.

I remember as a kid, having large bonfires on the beach, and our parents coming down and putting them out by covering the fire with sand. Many hours later, after our parents went to sleep, we would go and dig up the hot coals from the sand and use them to restart the fire on the beach. We would stay up all night and party. Life, as a kid, was so much fun. I was always in trouble, but hey, I was a kid.

If you like working with cast iron, check out Stephen Chastain's book series. I have them all. http://stephenchastain.com/store/

RedIron881 wrote:I worked with a guy that welding a lot of cast iron parts and used Vermiculite as a post welding heat treating. It slows the cooling down drastically. He had said that you'd put the part in the Vermiculite and leave for the night, come in the next morning and the part was still too hot to handle. I've never personally used it but if I get a cast iron job I'll be looking into it.

http://en.wikipedia.org/wiki/Vermiculite

just remember that some piston rings are plain cast iron with no chrome at all.

Silicon bronze does works probly the best but it not strong. If you want something with moreover strength I have had good results with nickle 99, some of the inconel rods work and we have this rod at work called Brutus and it works great. The most important thing is pre heat and post heat and cool down as slow as possible.