Welding Cast iron to mild steel

[Tim]

Before I got a chance to reply to a post asking me about welding Cast Iron to Mild steel...Do you use a Cast Iron rod to weld Cast Iron to Mild Steel? I thought I read in the Forneys welding manual a while back where you could use a stainless steel rod for joining Cast Iron and Mild Steel together.
Which rod would be used?
Thanks
Tim

[Dan]

Tim
A nickel base rod is the best choice. In my area, it is called Ni-rod. However, if this joint isn t being heated, then braze welding with oxygen/acetylene and a bronze filler rod is my preferred method for joining cast iron to cast iron or cast iron to steel.

[Guest]

I favor Certanium 889 stick rod for welding cast iron. It's a nickel base rod, and after welding I wrap the part in Fiberfrax or Kaowool (ceramic fiber cloth), which allows it to cool slowly. You could also use fiberglass cloth, too. I don't peen the small stuff, only the big weldments. There are a number or rods for cast iron, so ask your welding supplier for a suggestion.

Brazing will work, too. It requires the rod, flux, and oxy/acet equipment. Many times I've seen novice welders use the brazing technique, unable to recognize when they were getting co-hesion. Brazing is a co-hesive process, not a fusion process. You have to stir it up as your moving along a joint.[B]

[shortarc]

Just another trick I have used is to bury the piece in clean Oil Dry so it'll cool slowley. (if it's a small piece)

[Hobart Expert Rock]

HI GUYS........I TO HAVE USED NI-ROD.......BUT 9 OUT OF 10 TIMES I WILL USE THE OXYGEN (PROPANE)/ACCETYLENE OUTFIT FIR THIS ONE. I JUST FIXED MY CAST IRON SKILLET (DEER HUNTING IS COMMING UP) FOR CAMPING..........NEVER DID FIGURE OUT HOW IT GOT BROKE (HANDLE).....................ROCK.,[email protected] RWELDS.COM

[Mike Sherman]

Tim, the reason stainless steel rod works is the nickel in it. It will work in a pinch, but as the other posts say there are better ways to go. I use SMAW, GTAW and Powder flame spray. I believe it can be done with GMAW also, but I have never tried it. Welding cast iron requires good control of the cooling of the weldment except with the powder flame spray, it does not require controlled cooling. If you become good at cast welding, you will quickly gain a reputation that will follow you for the rest of your life. If I were to weld carbon to cast I would try buttering a pass or bead onto the carbon and one on to the cast (using NI-Rod) and then a pass down the middle to fuse the two together. Follow me?? This will help control the admixture between the filler the base metal. Brazing is also an excellent choice, I however, am not an expert in that field. Good luck.

[Tim]

Mike Sherman..Would you please explain

Originally posted by Mike Sherman
Tim, the reason stainless steel rod works is the nickel in it. It will work in a pinch, but as the other posts say there are better ways to go. I use SMAW, GTAW and Powder flame spray. I believe it can be done with GMAW also, but I have never tried it. Welding cast iron requires good control of the cooling of the weldment except with the powder flame spray, it does not require controlled cooling. If you become good at cast welding, you will quickly gain a reputation that will follow you for the rest of your life. If I were to weld carbon to cast I would try buttering a pass or bead onto the carbon and one on to the cast (using NI-Rod) and then a pass down the middle to fuse the two together. Follow me?? This will help control the admixture between the filler the base metal. Brazing is also an excellent choice, I however, am not an expert in that field. Good luck.

Mike:
Would you please explain "Buttering a pass" To me? I really dont know what that means.
Thanks Mike
Tim

[Mike Sherman]

I'm sorry, what I should have said was to run a bead of NI-Rod (the grade of which will depend on what you need for a finished product) on each piece to be welded and then weld them together. This is not always necessary but it will help. You will also need to preheat the cast and after welding you will need to slow the cooling down. Write me if I can help in any way.

[Tim]

Hey Mike....

Originally posted by Mike Sherman
I'm sorry, what I should have said was to run a bead of NI-Rod (the grade of which will depend on what you need for a finished product) on each piece to be welded and then weld them together. This is not always necessary but it will help. You will also need to preheat the cast and after welding you will need to slow the cooling down. Write me if I can help in any way.

Mike:
It does make sense to "Butter" a pass.
I wish I learned about this in welding school.
It really bites that the instructors never teach this.
I checked out a web site "www.jpcweld.com"
And there was a saying that went...
"If you dont have the time to do it right the first time...when you will find the time to do it again"
Mike...The ways told here in these posts will help me the next time I weld cast iron. Working in a weld shop...People bring in cast iron products that need to be welded. Even though I dont weld in my shop (For a living) My supervisor tells them to see me.
Hmmmm...I can weld cast iron but yet...When it comes to mild steel ......Like the cabinets that are welded in my shop...I am not allowed to weld them. Go figure!
Thanks Mike
Tim
Ps....This is not an advertisment..Its just to let folks know what we do make. www.so-low.com
So..please dont think this is an advertisment.

[Ed Heimbach]

Tim; I'd like to share some of my experences with cast iron welding.
On large castings, the safest way to repair a crack is to use what I call the cold method. Vee out the crack, drill the ends,(to keep the crack from spreading), and weld short sections using the back step method. Let each bead completely cool before starting next bead, peen bead during cooling(peening counteracts shrinkage stress).

On smaller castings like cylinder heads and engine blocks, I have found preheating to be easiest. I put the items to be welded in a charcoal fire to keep temperature induced stress to a minimum.
Prep item as above, place in a container(non flamable) which is large enough to allow complete access to area being welded.
Place charcoal in container and then set your casting in, fill all around with more charcoal and light.
After about 45 min.- 1 hour the casting should be warm enough to weld.
When done ,leave casting to cool in place (let the fire burn out).

I have had good luck with MG 289 , which is an all nickle rod,use about 1/3 less amperage than you would normally use on a mild steel wire, the puddle will be very fluid. Please note that nickle works the best in the flat position.

Welding mild steel to cast requires all the same attention to detail, as the cast iron has a much smaller coefficient of expansion than the steel.

These methods are by no means the only methods, or the "best" methods, but they are what I have found to work for me.

Good luck, and keep us posted. Best regards.

[Arbo]

I have had pretty good luck using flux core wire on cast iron. I do quite a bit of ornamental iron gates, etc. They are not structural welds, but they seem to hold up well. I only ever had one break.

[JPCWELD]

Sounds like you are welding some Castings or spearheads on I use mig or flux depending how far from the truck it is. just remember to tack everyting in good befor welding ,the cast what ever it is has a mind of its own .