Turning Scrap Metal Into Something To Work With

Blacksmiths will frequently work to a customer’s commission, and sometimes those commissions can be somewhat unusual. [Copperrein] had just such a piece of work come his way, a ceremonial sword to be made from a supplied collection of iron and steel items. To render them into something useful he had to melt them together, and the story of how he did that is particularly interesting.

We’re introduced to the Aristotle furnace, a fairly simple top-fed air blast charcoal furnace capable of melting almost any ferrous scrap into a so-called “bloom”, a lump of iron with some slag and carbon inclusions. These furnaces are often built as holes in the ground, but he’s made his atop a portable forge at working height to save bending over it for seven hours.

The source material was a very mixed bag, so the first order was to strip it in an acid bath of any coatings which might contaminate the resulting bloom. The parts, including things as diverse as a huge wrought-iton bolt, a scythe blade, and a pair of dividers, were then cut into small pieces one by one and fed into the furnace. They melt as they progress down through the furnace, resulting in a bloom of iron. The bloom is impure and will need significant working to expel any inclusions, but the final result will be something like the wrought iron of old. Let’s hope he has a power hammer, working the bloom would be hard work by hand!

If this catches your attention, you may be interested in a bit of blast furnace iron smelting. And of course, there is also our ongoing blacksmithing series to get you going at the anvil. You could even make a nail.

Via Reddit.

Thanks [Mike] for the tip.

16 thoughts on “Turning Scrap Metal Into Something To Work With

  1. On the wrought iron thing, I once saw what I would call a big (very big) taffy machine. It was working a big blob of hot iron and someone periodically scattered sand on the iron. The explanation was they were making wrought iron like was used for bridges. The sand melted and by the stretching of the “taffy” process it became long filaments in the iron. They said the end product was very strong, much less brittle, and nearly rust-proof. Any idea what that was? https://www.youtube.com/watch?v=Y7tlHDsquVM

    1. The sand adds silicon, which improves corrosion resistance and makes the steel more ductile. With wrought iron, the impurities and carbon inclusions are also formed into thin layers, and the corrosion of the iron can only advance along the layer, not across the boundaries, so the corrosion has to go in the long way around. These properties make the iron rust very slowly.

    2. We’d used silicone carbide in the foundry I worked at, though that was to make higher grade steel.

      Chromium can be added to make even higher grade, stainless steel though wasn’t where I worked. Nickel, Cobalt, Molybdenum, Vanadium and even Aluminum,Titanium and some other metals can be added to have unique stainless steel properties also.

    3. It probably actually was just sand (Silicon). They were recreating traditional wrought iron.

      At the time wrought iron was the result of relatively impure iron getting cast from a blast furnace into sand moulds. The resulting metal bars were called pigs, the iron was designated as pig iron. This pig iron was relatively impure and contained lots of slag inclusions. Before the early 1700s, furnaces created iron blooms with relatively large carbon content and lots of inclusions. These had to then be resmelted using pure charcoal (later also cokes) to burn off this carbon. When cokes was introduced as a fuel the iron bloom step was skipped and the output of the furnace was relatively low carbon pig iron. By heating the pig iron or resmelted bloom iron and beating the snot out of it in a finery forge, these inclusions were hammered out and the remains drawn out into long slender tendrils within the material. Due to these inclusions, wrought iron is a relatively ductile material (Talk to any blacksmith that has worked traditional wrought iron and modern steels. Traditional wrought iron is like working hot taffy in comparison).

      The modern process to recreate that is the “taffy machine” you witnessed. Low carbon steel is drawn and mangled around by the machine, while “slag” is introduced in the form of silicon/sand. The stretching and needing of the machine draws the inclusions into the long tendrils similar to the traditional forging process.

  2. I work At. All American Recycling in Austin Texas
    We sale metals back to the public. Cents to the pound. Some metals a little more like copper brass lead aluminium. But YES people can find some
    Useful junk at scrapyards. We get welders. craftsmen. I seen guys come for poles. Iron sheet
    For small touchs up projects. Just saying
    Make a Buck Save a BUCK.

  3. So a friend of mine has a forge but I have never been able to find any information on it and I’m hoping someone here has some leads. It’s called a duck forge and according to him there might be 3 of them left in the world that still work. He said it’s one of the only non-commercial forges that can do cast iron(this was almost 20 years ago so that may have changed). His brother took it apart and may have broken something on it before I got to see it working so I can’t describe it but it was super tiny, could fit in a 12 inch cube pretty easily(minus any air delivery device that I never did see). They are supposedly from colonial times. I’m sure some of what he said was incorrect but I’d really like to know what he had. Like I said, I’ve looked for ages for info but never found anything on it.

    1. It may be worth having a chat to a few of the guys over at https://www.anvilfire.com/
      Some of the guys over there including Jock Dempsey the owner have been around the industry longer than many of us have been alive :)

      I had the pleasure of having a chat to Francis Whitaker on there who among other things worked on a part of the handrail in the smithsonian. Having no idea who he was at the time I asked him in the public chat system if he was a blacksmith lol.. Total laughter erupted in the chat system as apparently everyone else knew who he was.

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