anyone here ever welded mild steel to cast iron? can it even be done? opinions and reliability factor?

I am wanting to just rotate the 2-bolt flange 90 degrees

 

It can be done, but it must be heated first... most guys use and electric "hot" plate used for cooking, to heat the parts first... see pics below...

 

I may be wrong about this but...... I always was taught not to mix dissimliar metals. I am not sure however if iron and steel pass electrons easily or not. I do know that having aluminum and steel next to each other is wrong though. Maybe someone with more metalurgical (wow 10 dollar word!!) knowledge will chime in.

PS that is a mighty fine weld job Mr.Big

 

How is it wrong?

Chances are, if your house is being fed (electrically) by overhead power lines (not your service drop), they are ACSR wire which stands for Aluminum Conductor Steel Reinforced wire. A steel strand runs in the center of the aluminum conductor.

Unless you mean trying to weld them together (even possible?)

Now copper and aluminum is a different story.

 

Cast iron can be welded with "Nickel" rods (brace yourself they're expensive) basically any ferrous metals (metals that contain iron particles) can be welded, and the same with non-ferrous. If you heat cast iron and use a 6010 welding rod you can do a pretty good job. (I've broken a few vices in my day)

 

I haven't met an experienced welder yet that doesn't claim to be able to weld cast iron. However, I haven't yet seen a successful weld on cast iron. It will look nice and stick together, but at a low strength. Do a penetrant-test and you'll see the cracks. To give it some chance of success, a pre-heat and post-weld-heat-treat helps. I stay away from welding cast totally. I do hear that some high-nickel cast irons are weldable, though.

 

When dissimiliar metals are touching they corode due to the transfer of electrons that becomes present due to an electrolyte ie. water.

 

^^^yup we rent half of our shop to a on site welder and he showed me the rods and book on how to ,and what you need to weld cast...there is rod to get the job done tho

 

From "No Country for Old Men"

Carson Wells: What did you do?
Llewelyn Moss: Welder.
Carson Wells: Acetylene? Mig? Tig?
Llewelyn Moss: Any of it. If it can be welded I can weld it.
Carson Wells: Cast iron?
Llewelyn Moss: Yeah.
Carson Wells: I don't mean braze.
Llewelyn Moss: I didn't say braze.
Carson Wells: Pot metal?
Llewelyn Moss: [annoyed] What did I say?

lol

 

I have welded on an ear that broke off a 5.3L, I tigged it and used 99 Ni Lincoln stick electrodes and just knocked off all the flux. They were about 36.00 a pound. I couldnt find tig filler rods in 99 Ni anywhere.

 

I was told never to weld cast Iron. It is a poured metal in to a mold. Never to be heated, but I guess it can be done. From the above pick of the manifold. I just bought a new steering knuckle since I was un sure of the unknown damage it could have over time. I did not want the knuckle to break as I was driving down the interstate, that would have been a hell of a ride.

 

I would NEVER suggest to repair a suspension component like a spindle/knuckle, you made the right choice IMO.

 

Thanks that is what I did. So I take it is cool to weld cast iron on like manifolds just not serious parts like suspension.

 

Ahhh yes.....classic

 

They make a stick rod desighned to weld cast iron, we do it all the time. I have often used inco 082 to weld it to mild steel.

It will work, and it will be strong. Just has to be done right.

LionelC

 

It can be done. My dad owns an engineering tool and die shop that has some very experienced welders... You guys are right on, however, leaving out one thing. Many people pre-heat the metal, and that is correct. But the key is that you have to bring the weld back down from temperature slowly (can't remember the exact temperature) to ambient temperature. If you just weld the cast iron and let it cool on its own, this is a common cause of stress and cracks. Also, if you're welding two dissimilar metals with different properties (be it heat, or elemental makeup) they will eventually break apart. The two metals will expand and contract at different rates, among other different reactions causing them to stress crack and eventually break.

 

Welding two dissimilar metals happens all the time. All the equipment that process oil and gas do it all the time. I see it all the time anywhere from High pressure pump castings to Reactors

 

 

A local cast iron repair specialty shop fixes ALOT of broken blown out cast iron cylinder heads from around the world. (Cast iron Repair 360-657-7660) (Cast Iron Mike as he goes by) He pre-heats the cast iron to red hot in a brick oven that he builds around the part. He uses propane torches to pre-heat. Then he removes a brick to gain access to the area to be repaired, and then uses an oxy-acetylene torch to weld it with a pure cast iron rod about 1/2" in diameter. He then lets the head slowly cool over a 12-24 hour period by wrapping the red-hot head in thermal blankets and then throws it on the floor and covers it with sand to slow cool.

Now......If you are welding a non cast flange onto cast iron, use stainless steel flange, as stainless steel has "similar" expansion and contraction rates to cast iron vs. heat. Less chance of thermal cracking with a red-hot turbo manifold. Once you heat cast iron to red hot and not slow cool, it becomes harder than the hubs of hell, and almost impossible to machine. Heat a cast iron part to red hot, then let it cool at room temp, and TRY to run a tap through a hole. NOT gonna happen! Been there, done that. I have repaired lots of Ford FE heads, and 460 heads with broken exhaust manifold studs, by TIG welding a stud into the head with a TIG wleder and stainless rod. Works pretty dang good!

 

I Tig welded a cast Iron exhaust manifold about three months ago. I used a Nickel rod. There like $3 each! That was the first time I have ever tryed to tig Cast Iron. I had no idea what to do. I just knew i had to use a nickel rod. I didnt heat the manifold but i did have a hard time getting the nickel and iron to bond. Once the Cast Iron warmed up from the welder heat it worked out great. I would love to try and weld another Cast iron manifold now that I know how to do it... Oh and that manifold is still holding up strong!


Justin