Welding cast steel
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Unlikely that it will hold but here is what you do to try
First grind edges down "wide taper for welding in valley"
Prepare a bucket of plenty of size, 1/3-1/2 full of floor dry
Get a good pair of welding gloves and proper welding attire
Heat both halves with torch till orange, weld hot, and quickly submerge in the floor dry and finish filling bucket with floor dry
It will take at least 12 hrs to cool, the slow cooling is a key factor in this process, I use a wire feed, my brother uses nickel rod? Maybe? Can't remember for sure, he is the welder by trade in the family
First grind edges down "wide taper for welding in valley"
Prepare a bucket of plenty of size, 1/3-1/2 full of floor dry
Get a good pair of welding gloves and proper welding attire
Heat both halves with torch till orange, weld hot, and quickly submerge in the floor dry and finish filling bucket with floor dry
It will take at least 12 hrs to cool, the slow cooling is a key factor in this process, I use a wire feed, my brother uses nickel rod? Maybe? Can't remember for sure, he is the welder by trade in the family
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I believe it is nickel rod you would want to use. I personally have never had much success welding cast but I have seen a few welds where the guy knew what he was doing and it worked.
Agree with what SW said. The main issue with cast is that it will crack if you apply sudden heat (or cold) to one area, so you need to heat it and cool it evenly. An oven is best, but a gas torch does fine if you move the flame over the whole surface of the part.
We have some expensive rods specially for cast, but I've found that plain old mig works very well.
I just dig a hole in the sand and bury it when I'm finished welding. No shortage of dry sand around here
We have some expensive rods specially for cast, but I've found that plain old mig works very well.
I just dig a hole in the sand and bury it when I'm finished welding. No shortage of dry sand around here
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Has anyone welded cast with 7018? Not like nickel rod but may work in a pinch. Have done it some but always preheat, not weld more than an inch at a time, peen it good after each weld, and cool slow. Might not hurt to also keep it hot in a forge or with a torch to take out stresses. I've welded wagon seat springs this way and they never broke or lost their spring.
Are you talking about cast steel or cast iron? Different material. Cast steel does not weld much different than most other steel. Now cast iron is tricky to weld. Use a high nickel or stainless steel rod. Pre heat the casting till it turns blue. Don't want hotter or its hard to weld and don't want colder or the weld might crack. Let it cool off naturally. DON'T QUENCH IT EVER!!!! Don't use regular rods cause they don't have the flexibly as the stainless rods. With the proper pre heat any rod can stick it but it will crack again in 90% of cases.
Another trick with the stainless rods is to use them on the root pass when welding thick steel together. Again because of the way stainless will flex. So when the weld cools it will not crack the root pass.
One type of cast iron can not be welded. It is really brittle, but when hit with a grinder it seems soft
Hit this piece with an angle grinder. If the sparks hardly shoot any distance at all and the material seems soft its cast iron. If the sparks shoot far just like normal metal. Than it is cast steel.
Another trick with the stainless rods is to use them on the root pass when welding thick steel together. Again because of the way stainless will flex. So when the weld cools it will not crack the root pass.
One type of cast iron can not be welded. It is really brittle, but when hit with a grinder it seems soft
Hit this piece with an angle grinder. If the sparks hardly shoot any distance at all and the material seems soft its cast iron. If the sparks shoot far just like normal metal. Than it is cast steel.
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All sounds good might even pre heat the " floor dry" or sand in very hot oven or forge.
:54:
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I have good luck welding cast iron. Do as stated previous. My best advice, take your time. Keep in the back of your mind "an hour per inch"
I have never been able to over heat or cool something and it works. Just preheat with torch. Then weld slowly to not over heat the welding area. You can hear it poping and cracking if you push it to fast at all. An hour and inch!
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A lot depends on the size of the casting needing to be welded of it's not practicable to pre heat entire piece cause of size than yes I would recommend welding cold very slowly with first few passes using nickel rod as the carbon from the high carbon content casting will be diluted into the nickel. Stainless is also the nearly the same. Than continue filling with 7018. Another good option if able to preheat the entire piece is to. Braze with bronze rod. Ductility is still good after. The key again is even preheat and slow cooling.
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I have done similar to Big Red Tractor. I have used 7018 and nickel cast rods as he has recommended. I avoid using brass although it works. Once you start with the brass, you can't weld with normal rods unless you grind all the brass away and remove it entirely. It doesn't mix with normal welding. Sometimes very old cast which has been in contact with oil works best with brass.
Another trick some people use when welding is to drill a small hole at the ends of the cracks. It relieves stress and keeps it from cracking. Works if you have to weld a engine block which has a frost crack. Still best way is preheat and weld while hot with cast or nickel cast and cool down slowly.
Another trick some people use when welding is to drill a small hole at the ends of the cracks. It relieves stress and keeps it from cracking. Works if you have to weld a engine block which has a frost crack. Still best way is preheat and weld while hot with cast or nickel cast and cool down slowly.
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According to my knowledge and I believe it is nickel rod you would want to use. I personally have never had much success welding cast but I have seen a few welds where the guy knew what he was doing and it worked.
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If it is a break in cast Iron, throw it away and buy a new/secondhand part.
Even if an expert welds the cast, there`s an extremely high chance it won`t last, if placed under stress. The fact that it broke right there, in the first place, is a good indication that there is a stress point right there.
I`d be guessing here, but the strength of a really good cast iron weld at best, would be about 70% as good as the original
consider brass rod, can use propane/oxygen head on torch as oxy/acetyline can be too intense, a carburizing flame, preheat, and use fluxed rod. will need to throw it in the floor dry to slowly cool. the brass is just as strong, and has some degree of flex and shock absorbing.
i have an old stocktank half full of sand for welding cast. I use an old forge that i put a propane burner in and take my time in it seems to work well. I dont do realy important things. They go to a machinest in town and hes realy good! Ive broke hubs on my pull tractor and he welded those up for me. So a good weld job on cast will hold up.
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Hello 361turbo
X2!!! Cast iron gets welded every day. Probably some getting welded somewhere in the world right now as I type this.
oking-with-stick-s No reason to scrap a part just because it is made out of cat iron (for a reason) & it happened to break. That being said, unless it is of a smaller size & it would cost more to repair than replace. But then again, that applies to all parts I guess, no matter what they are made of.1 - 20 of 21 Posts
