Cast Iron

[Karn3]

Some cast iron has recently fallen into my possession and I was curious whether or not this is of any use in the forge at all? Can it be turned into useful product or is there some use that it can be put to in it's current form? Many thanks in advance.

[Timothy Miller]

cast iron can not be forged. It is brittle and will melt at lower temperatures than steel.

[ThomasPowers]

According to the UN manual on blacksmithing in backward areas you can heat mild steel and a piece of cast iron and crayon it onto the mild steel leaving a higher carbon steel layer for edge tools.

Other than that Cast Iron is pretty much useless in the forge.

[MattBower]

But build yourself a foundry and have fun!

[Tom Allyn]

If it's in the form of cookware then season it up and use it. Nothing better.

[teenylittlemetalguy]

According to the UN manual on blacksmithing in backward areas you can heat mild steel and a piece of cast iron and crayon it onto the mild steel leaving a higher carbon steel layer for edge tools.

Other than that Cast Iron is pretty much useless in the forge.

I used cast iron like this to case harden the tips of a caliper I made and was happy with the results. allowed me the ease of forging with mild steel and extends the life of the caliper tips (because I am one of those guys that refuses to believe that calipers aren't scribes)... It is super easy (and fun) to do, everyone should try it at least once.
I learned about it from a fairrier we had doing a workshop for our group.

[Drewed]

I use a cast iron skillet as my fire pot....

[MattBower]

According to the UN manual on blacksmithing in backward areas you can heat mild steel and a piece of cast iron and crayon it onto the mild steel leaving a higher carbon steel layer for edge tools.

Other than that Cast Iron is pretty much useless in the forge.

Now that I think about it, Don Fogg once mentioned that he had welded up cast iron into steel (with some wrought, by the sound of it). It took a little searching to find it, but here's his very brief description of what he did:

I have made steel by making a paddle and stacking the cast iron pieces on top then carefully consolidating it and folding and welding. I have an article on a Japanese smith who made his blades this way so I tried it. Don't heat it up to normal welding heat and whack it, the cast iron goes everywhere.
* * * *

I made a paddle out of wrought iron and sort of folded it up around the cast iron pieces. I was working in a coal fire so don't have the temp numbers, but cast iron melts at a relatively low temp compared to iron. I do remember over heating one of the tests and having molten cast iron splash over the whole shop. It takes a while to consolidate.

In the process of finding that I also ran across a post in which our own Ric Furrer mentioned pattern welding CI with wrought: http://forums.dfoggk...showtopic=17864 I note that he seems to indicate that he gave it up long ago, which may suggest something about how practical the process is.

But, y'know, if you're in a bold and experimental mood, there's always that . . .

[knots]

I always wondered what the smallest practical size would be for a puddling furnace.

[MattBower]

I always wondered what the smallest practical size would be for a puddling furnace.

We had some discussion about that late last year. I thought for a while that Grant Sarver was going to take the bait and make a little one . . . :)

[JNewman]

Funny this has come up. I was just asked today about forging white iron for an commercial application, my first thought cast was you cannot forge cast iron but there is apparently a company in Australia doing it. This could develop into a fair bit of steady work so I am going to give it a try . I have been looking on line and have found a few engineering references that claim cast iron can be forged when it is in an austentitic state. I don't know anyone who has done it and I am sure it will not be easy if it is even possible.

[Timothy Miller]

I thought white cast iron was just quenched or chilled grey cast iron. I think if you were to forge cast iron it would have to be done with a slow application of pressure not a high impact blow. I was talking to a guy who was building presses forge castings in dies I didn't really understand what he was tiring to do but he seemed to know what he was talking about. He did mention that he was using cast iron. I walked away from that conversation scratching my head.

[pkrankow]

Certain grades of cast iron can do many things, others...not so much.

What are the general dimensions? scrap parts? large plates or bar sections? If you have big pieces in convenient dimensions then you can use them as part of an assembly for some purpose or another.

I always wanted a 2 ton glue weight <G>

Phil

[bigfootnampa]

White cast iron is not the same as grey cast iron. The grey is much more common though. In the cast iron family are also malleable iron and ductile iron. These last two have some forgeability. Here's a link: http://en.wikipedia.org/wiki/Cast_iron

[John McPherson]

I seem to remember Tai Goo mixing broken bits of sewer pipe and bottle caps, then welding it up to make steel for a blade, but that was years ago on another forum.

[JNewman]

I thought white cast iron was just quenched or chilled grey cast iron. I think if you were to forge cast iron it would have to be done with a slow application of pressure not a high impact blow. I was talking to a guy who was building presses forge castings in dies I didn't really understand what he was tiring to do but he seemed to know what he was talking about. He did mention that he was using cast iron. I walked away from that conversation scratching my head.

My understanding is there is less silicon and then it is chilled. I suspect you could be right on the pressing issue. I forged a bunch of brass for an engineer and metalurgist last year for metalurgical reasons. Forging it under the hammer caused crumbling but I was able to swage it down to size under my hydraulic press. The containment of the swage and the relatively slow squeeze of the press combined together to allow the forging.

[Karn3]

Wow, thanks for all the replies guys. I didn't expect it to generate this much interest! It sounds like there may be plenty of uses I can put it to, I'm glad I didn't override my magpie tendencies this time. The cast I have is some decorative pieces off some old sewing tables; the ones with the wheel and pedal. I'll post some pictures for everyone to see.

[pkrankow]

Wow, thanks for all the replies guys. I didn't expect it to generate this much interest! It sounds like there may be plenty of uses I can put it to, I'm glad I didn't override my magpie tendencies this time. The cast I have is some decorative pieces off some old sewing tables; the ones with the wheel and pedal. I'll post some pictures for everyone to see.

Sounds like you may have the prettiest forge in the neighborhood. Using the sewing machine legs for forge legs is probably the best use.

Phil

[ThomasPowers]

I've tried the pattern welding of cast iron and steel after reading about it as a possible method used in early times to make blades. Since then I have read a lot more modern research and believe that that process was more of an "urban legend" than reality.

When you heat such a billet to welding heat for steel and smack it molten CI files out in large gooey drips that fly through the air decarbing until they *BURST* into sparks when finally the iron gets to burn after the excess carbon goes away.

Forge welding is generally a way of lowering the carbon content of a material so if you are willing to babby it enough you can get it into a steel range.

I don't know about micro puddling; but I did read that Kelly did his experiments on the Kelly/Bessemer process in a refractory lined barrel so *that* can scale pretty small!

[MattBower]

I'm actually pretty confident that you could puddle in something the side of a medium size gasser with a high output ribbon burner (with a suitably shaped floor of high alumina castable). But I don't want to do it badly enough to invest the time and money. I have way too many half-finished projects going, as it is.

[Timothy Miller]

I don't think white cast iron and gray cast iron are actually two different metals. They are just two different states of the same material. As said above there is more silicon added in cast iron that is intended to be white cast iron but if you heat up regular cast iron and cool it quickly you will get white cast iron. I have disassembled some old decorative rails and iron beds that were constructed by casting iron around wrought iron bars. You can see both white and grey cast iron in the same casting when they are fractured. The white cast iron is super hard harder than files in fact and brittle it will destroy your hammer faces, The grey iron is softer and requires less force to crack with a hammer. Where it is close to the wrought iron bars it is white and further away it is is grey iron. The wrought iron bars acted as heat sinks and chilled the molten cast iron faster than the cast iron that was not in contact with it. I can provide photos if you doubt me.

[Timothy Miller]

Keeping all of this in mind 99% of the time cast iron is useless for making things at the forge. Its not really forgeable most of these uses discussed are fairly esoteric and beyond the skill level of all but advanced smiths. I would shy away from using it to hold up your forge unless it is fairly thick in section or well cross braced with steel straps. I have fixed more than my fair share of cast iron lawn chairs and love seats that broke from being careless handled. you don't want a forge full of hot coals falling over from a broken leg.

[Frank Turley]

My friend, 'Cracked Anvil," says that cast iron is an amalgam of sawdust, molasses, and baby caca.

"White Cast Iron. A cast iron with virtually no graphite. The carbon is present in a matrix of fine pearlite as large particles of iron carbide..."
"Materials Handbook"

[Timothy Miller]

My friend, 'Cracked Anvil," says that cast iron is an amalgam of sawdust, molasses, and baby caca.

"White Cast Iron. A cast iron with virtually no graphite. The carbon is present in a matrix of fine pearlite as large particles of iron carbide..."
"Materials Handbook"

Yes because the carbon is present as carbides in white cast iron not graphite the carbon is still there it is in a different form this is the result of the rate of cooling.

[Robakyo]

Could it be utilized as the carbon component in canned damascus? Could you mixed a good quantity of mild steels shavings and small cut-offs with a bit of cast iron? Wouldn't that keep the CI from spraying everywhere? Would the CI carbon migrate into the low carbon steel enough to produce at least a medium carbon steel? Should you add something else as well to the brew? I have been intrigued by that notion for some time.

Of course, if such were the case, I would be unable to predict the ratio of CI to mild steel or low carbon steel. Thoughts? -Robert

I am still learning, so please don't rip me apart. :(