Iron smelting in the early medieval slag drop shaft furnace, making iron

Because of Covid-19 the Long Night of Museums in many museums was canceled but some of them decided to do something despite the virus. Historical and archeological Museum in Elbląg prepared a virtual show about the metallurgy in Truso - Viking age emporium.
#officinaferraria

[@paulorchard7960]

Tough work six hundred years ago no easier today to recreate the simple history! Thanks guys, really interesting!

[@joshschneider9766]

By the fourteen hundreds they had blast furnaces that totally took over for these and rendered them completely antiquated.

[@Allyourbase1990]

I’ve always wondered how they got furnaces hot enough to melt Metal back then . This is so cool

[@timberwolf1575]

Excellent work. Understanding how much work this is/was makes you appreciate modern furnaces, blowers, and power hammers more. A lot of blood, burns, and sweat goes into a smelt.

[@alexadamson9959]

This must have been one of the most shitty jobs ever. But at the same time, you look absolutely badass doing it. There’s something about dragging a ball of flaming metal around and then proceeding to beat the shit out of it with a hammer that commands respect.

[@3vanguardofthephoenix335]

I think emptying chamberpots would be more... shitty

[@maksdampf]

This is a very decent size of bloom for the size of oven! You must have nailed the mix of ore, charcoal but also temperature and drought. The smelting experiments i participated in were by archeologists, but we didn't have anyone with that much experience. We had 3 ovens and most were slightly larger than yours. Our bloom was either much smaller ore completely spread out in tiny iron particles and slag. A lot also just burned away with the oxygen when we opened it i think. Great to see in a video how it can go when it is sucessfull.

[@officinaferraria]

The ore i use is quite good quality. In this furnaces size i am able to smelt up to 15 kg bloom.

[@ricardoaquino1562]

Great job!, thank you all for showing how hard is to get metal. 👍👍🙏

[@jollysquidmedia]

So cool. Ww are working on an animated project which includes the smelting of Iron in Nigeria in 800BC and looking for references for goat skin furnaces, found this. This is so gratifying to watch. Thank you for making this video.

[@fourgedmushrooms5958]

Looks like fun! Love the hand forged bucket ❤

[@martinpanks992]

The effort to reward ratio was crazy. The amount of iron you got from all that ore and charcoal was pretty minimum and that's why metal was a great currency back in those times as it took great effort to recover such small amounts.

[@jsmythib]

iron was never a great currency. Although it was the last for at least of few civilizations. Agreed though- Huge amounts of fuel and labor go into a small output. In fact, they still do! Cheers :)

[@martinpanks992]

@@jsmythib I'm not talking about the raw iron as currency but once it was made into swords and things then it could be traded..

[@jsmythib]

@@martinpanks992 My 6am Sunday morning response, 'barter' - finished goods. Yep :)

[@Bialy_1]

@@jsmythib Huge amount of "Żelazne grzywny siekieropodobne"(Axe-like iron currency) also caled in Poland "płacidła" that you can translate as "paying object" were found not so long ago in Poland. "available photos show that they were packed into one large block. They were probably "packed" in bundles of up to 20 pieces. There were probably 510 bundles themselves. Such conclusions can be drawn not only from the way they were arranged relative to each other, but above all from the found remains of string and bast. The treasure was located in a sandy pit (dig-in), which was covered with boards or fir and oak planks securing the walls. The ditch had dimensions of 108 x 210 cm and a depth of about 100 cm. It is important here that it was made before the aforementioned defensive rampart was built. On this basis, it can be concluded that the grzywnas must have been made no later than the second half of the 9th century. This was confirmed by radiocarbon tests carried out later." A total of 4,212 were found, which translates to 3,630 kilograms. That is, over 3.5 tons of iron.

[@jsmythib]

@@Bialy_1 Consider me more enlightened to Iron currency. Its still has value today. We cant say that for many others.

[@varun009]

Besides trapping, the American fur trade, which resulted in many of America's great trails being blazed, was carried on the back of steel. Native Americans would trade many pelts for steel in the form of knives initially and later hammers and raw stock. Very interesting stuff. I was in a village in India about 17 years ago and my mother thought to bring them some mirrors. I remember us giving out these tiny 6x6 mirrors and they were stoked! Apparently, they only had one in the village and it in the bathroom of a government building. People rarely had access to it. It's so easy to take for granted the technological, industrial and logistical apatatus that makes mirrors (something once highly prized) something disposable. Amazin.

[@Hyratel]

and we're now on like... 5th or 6th iteration of "mirror" - first was highly-polished copper or brass (very high maintenance), then came proto-industrial glass and Silvering processes making a Silver-on-glass mirror an elite luxury. then the advancement to Float Glass brought it to the masses. and then more recently we've shifted from Silver backed mirrors to Aluminum backed mirrors

[@JS-jh4cy]

Good, way to work up a sweat, and getting something useful done, rather than just going to a damn spa

[@MrThijzer]

Very well done, especially the bloom forging !

[@officinaferraria]

Thank you Thijs :-)

[@dieselphiend]

I have to say, this is ideal as opposed to an automatic blower. You have so much more control over the amount of airflow at any given time. I was just watching another video in which the blower was so strong it was blowing their ore and charcoal right out the top. It's just more work.

[@officinaferraria]

Yes. U r right, bellows gives much more control to the process and are more historical one.

[@bonbonpony]

It also seems to be a good idea to have two bellows to work in parallel, as in this video. Then one of the bellow is still blowing while the other one is restoring, maintaning a constant flow of air :)

[@jonash5320]

@@officinaferraria did you end up with cast iron due to all the coal? If so how do you reduce the carbon content of the iron to more useful concentrations?

[@officinaferraria]

@@jonash5320 i can control carbon content by charcoal/ore ratio. Less charcoal gives less carbon in the bloom (in theory of course)

[@sygnusadun4832]

@@officinaferraria whats your ideal ratio? I see many people saying that 500g of ore to 2kilo of charcoal.

[@jawdatfares2831]

Thanks again that was awesome to see keep up the good work we love you guys,,,that was awesome,,,we ont Moore of this project, s

[@cvdheyden]

Good job guys!! A huge loop, very impressive!

[@richardcook555]

Do you add any flux like limestone or shells with your charcoal and ore? Do you roast the ore first? Very nice video.

[@officinaferraria]

I do not use any flux. No, In this experiment I didn't roast the ore (it is hematite ore and roasting is not necessary)

[@retheisen]

Once the bloom is excavated from the bloomery, there's not much chance of reheating it. They are working against the clock to get the metal forged into something usable.

[@GeorgiDimitrovX]

Crazy how they filmed this in the 14th century

[@officinaferraria]

X century:-)

[@Barmaley80x]

Сложнее всего было с цифровыми носителями.

[@Illien0]

Good video, thankyou for posting!

[@huntergatherer8972]

If/ when society collapses through some apocalyptic event, this is the best we are gonna be abla to do lads, so let's all learn how to do it.

[@JS-jh4cy]

Shit, almost burnt the cottage or house down

[@bondvagabond42]

How much charcoal and how many hours on the bellows to make how much iron? Thanks, great videos.

[@py2rpjrubens450]

A Big job! TNX for sharing! 73 from Brasil

[@domenigo97]

Very well done I would love to know how high the carbon content is at this point. Am I right if I assume that it is rather high? I really don't know much about metallurgy

[@officinaferraria]

The carbon content in the iron bloom depends on the temperature in the furnace and the charcoal/ore charging ratio. Usually, it is rather low carbon content. Low carbon, soft iron this is result what we want to get.

[@domenigo97]

@@officinaferraria Allright, thanks for the explanation 👍

[@newageofsail3877]

@@officinaferraria But then not so very useful for knives, axes, swords, gun barrels, that need to be high-carbon, high-tensile steel.

[@rogerthedodger5788]

We are witnessing the death throws of the bronze age. A huge technological leap for mankind. A metal that could be repaired if broken unlike bronze.

[@WildBearFoot]

Bronze can be forge welded, it's just easier to recast it. The only advantage iron has over bronze is added strength and wear resistance.

[@paulsmith-y3e]

Just what I need for my students thanx!

[@caladin002]

How do you know how high/low to punch the hole to bleed off the slag?

[@officinaferraria]

when slag starts to block the blowing hole than i make a hole about 5-10 cm below slag level.

[@joshschneider9766]

Ive always wondered if it would be nore efficient to powderize the charcoal. And maybe mix with the ore and maybe charge both at once. Melting silica mix down into glass for blowing and casting is sooo much easier.

[@officinaferraria]

For the smelting process to proceed properly, spaces are needed between the pieces of charcoal, pulverization will result in loss of circulation in the furnace.

[@newageofsail3877]

@@officinaferraria In traditional Japanese tatara smelting, the tatara is initially loaded with alternating layers of river sand and charcoal, then lit, then more charcoal is added during the smelting process. See this video of the Nittoho tatara smelter: (kzbin.info/www/bejne/pYjalnxjpLydZrM).

[@thesavoyard]

So he molten liquid coming out was silicate?

[@officinaferraria]

It is slag, mosty iron silicate

[@roeberdt-bT.1021]

... Is that just iron or is that a steel?,... ... absolutely beautiful I'm any case. Thank you for the post, appreciated absolutely.,...

[@officinaferraria]

It is very low carbon content steel, less than 0.1%. But historicaly it was called iron.

[@roeberdt-bT.1021]

@@officinaferraria Thank you for saying so, i was wondering since my brain wants to say it would be possible and it does make sense that it would come out as iron since that's a pretty extreme temp already. Once again, thank you for the post and reply/explanation.

[@jessicag630]

Great re-enactment. Do you have any videos discussing where they sourced the iron ore and how they recognized and collected it?

[@officinaferraria]

No, but I am thinking to make a video about iron ores.

[@onanysundrymule3144]

Kind Sir, what would be the proportion/ratio of iron ore to charcoal, by measure of weight please. Kind regards.

[@officinaferraria]

ratio is 1:1

[@wullebulle123]

what is that lava flowing out made of

[@officinaferraria]

It is slag. Mostly it is iron silicate.

[@thiernosow11]

Incredible, this is exactly how we do it in Africa too, funny how we came up with the same ideas while separated by thousands of kilometers

[@romelcasillas2286]

*in the old days* "Hey guys, let's heat up some dirt and when it's all cool looking let's beat it with big hammers to see what we can make". 🤣

[@SenorTucano]

How much of the iron bloom is lost in the hammering process?

[@officinaferraria]

during whole iron bloome processing (compacting by mallets, forging, and forge-welding) there is 50% to 70% losses of the original weight.

[@retheisen]

I kinda want one of those shirts.

[@evgeniykhalzov4725]

Интересно еще и литьё бронзы. Как древние металурги догадались совмещать медь и цинк, что.ы получилась бронза. Хотя железо это тоже интересно.

[@officinaferraria]

copper and zinc alloy is brass, bronze is copper and tin alloy.

[@christianvoss8614]

The beginning of this video sounds like inside of Mordor or something

[@reidoレイド]

how many kilograms of coal does it take to make an iron?

[@officinaferraria]

about 40 kg

[@reidoレイド]

@@officinaferraria thanks

[@raphlvlogs271]

why were they using wooden hammers?

[@officinaferraria]

The iron bloom is very brittle just after extraction from the furnace that why we use a "soft" wooden hammer and wooden anvil.

[@evansmartin7681]

8:55 what is this cinematography xD

[@cesiusmok]

musi pan zmieszać węgiel drzewny z grubą korą z sosny i brzozy 1:1 , 1 cz węgla , 0,5 kory z sosny , 0,5 kory z brzozy. to da wyższą temperaturę w dymarce. glina do konstrukcji dymarki musi być rozrobiona z przesianym przez sito popiłem drzewnym z drzew liściastych(wapno), co zapobiegnie pękaniu dymarki w czasie wytopu.

[@officinaferraria]

Wyższa temperatura nie jest potrzebna a bardzo często jest problemem w procesie dymarskim. Muszę Pana zmartwić ale kora drzew jest mniej kaloryczna niż węgiel drzewny i wyższej temperatury nie da. Co do pękania pieca to nie stawowi to żadnego problemu, te urządzenia były zazwyczaj jednorazowe.

[@indicator27]

to what purpose does the layer of dirt serve, separation from the wood ash from i assume logs to start that fire, and the real charcoal, to burn it slower? WHOAAAAA THAT ISNT A FLAMING INGOT THAT IS A METEORITE

[@dogodogo5891]

hi this is so amazing, if u had ore with low enough granular size say almost like talc powder, will it reduce energy consumption and increase yield of pure Fe?

[@officinaferraria]

rather no.

[@dogodogo5891]

@@officinaferraria any reason?

[@branni6538]

@@dogodogo5891 iron yield=yes. Energy consumption=no. There are ways to conserve energy and lesson the consumption of energy expenditure both in terms of carbon char used and bowls of porridge used to pump the bellows. None of which are shown here. You,'ll have to figure it out.

[@juozaskavaliauskas8844]

Labai patiko!

[@kevinstacey2231]

Artisian iron?

[@richardwilloubly8285]

Enjoy your work but fear of the metal can’t come into the forge.but he will learn

[@MrWTPunk]

Good work, good video 👍 It is so silent without electric blower... Was the bloom containing a good amount of carbon? Also, do you know of to obtain high carbon steel everytime? Maybe letting the bloom longer in the furnace?

[@officinaferraria]

the goal of this experiment is to get low carbon alloy. I carburize it in different process. To get high carbon bloom directly in the furnace, the ore/charcoal ratio must be changed, more charcoal less ore. The hard wood charcoal gives usually better bloom carburize.

[@MrWTPunk]

@@officinaferraria Thank you for your answer. If I link good in my head, you carburize it in an Aristotle furnace, after. Why? What are the advantages to get iron and then proceed to another step to get steel? Good to know for hardwood. Do you know both ratios? Sorry for the amount of questions

[@MrWTPunk]

@@officinaferraria I was thinking about it... Maybe what you get after you carburize the bloom is near Oroshigane, so the steel you get doesn't need to be welded "at nauseam"?

[@bonbonpony]

@@MrWTPunk My guess is that it's better to carburize it afterwards because the iron is more clean at that time, and it might be easier to control the proportions. Also if you add more carbon to the bloomery, it might get wasted anyway during the processing later, so it would be rather pointless.

[@nathanfielure4305]

Where's Snow White and the other 3 dwarves?

[@dieselphiend]

Why not let the entire thing just cool slowly? Let it sit a full 24 hours before breaking open. Wouldn't that produce a better end product?

[@officinaferraria]

The iron bloom must be extract as hot as possible if not there is no way to clean it up (there is lot of slag which should be remove) and compact.

[@dieselphiend]

@@officinaferraria Couldn't you just reheat it for consolidation?

[@officinaferraria]

The iron bloom inside the furnace is cover by slag and when the slag is liquid it is easy to remove it. The bloom extraction when the furnace is cool down is very difficult so that's why we do it when the furnace is still hot.

[@dieselphiend]

@@officinaferraria Thank you for the explanation.

[@RodCalidge]

They NEVER tell you what the furnace is made of. It obviously can stand the high heat. Someone clue me in, please.

[@jupa7166]

It seems to be clay, it turns into ceramics which is quite heat-resistant. Maybe silica sand can be mixed into it? Don't know specifics.

[@pokeweed10k15]

Mud

[@thurst6510]

Bad ass!

[@intactsaphir5191]

bonjour, combien de tonnes de bois pour fabriquer 1 kg de fer?

[@hmidasliman6504]

100 kg peut etre?

[@r0llinguphill483]

Man I love staring at a bucket while they work the bloom

[@Zx_Wizard]

Красавцы! Глаза берегите! Почему не все в очках работают?

[@alexa.davronov1537]

Хопа, русскоговорящий! Тоже историю металлургии изучаем? Печь называется сыродутой.

[@Zx_Wizard]

​@@alexa.davronov1537 🤝Так давно изучена и активно мной используется! И такая примитивная технология, в том числе! И всё таки! Какого чёрта, они без очков!? 🤔🧐🥸😎🤓 😮🙂

[@alexa.davronov1537]

@ Балбесы потому что.

[@bonbonpony]

Skąd wzięliście rudę i jaki to rodzaj rudy? Ciemny proch, więc wygląda na magnetyt.

[@officinaferraria]

To jest przeprażony hematyt. O ile dobrze pamiętam to kanadyjski.

[@NSP70]

No eye protection. Brilliant.

[@dwayneskinner6984]

Same thing I was thinking. Medieval or no no excuse for not protecting yourself

[@ЭнтальпияПлюс]

После такого видео на обычный молоток или гвозди смотришь немного другими глазами... Мы избалованы современной металлургией.

[@tothista4477]

Super big bog!

[@larrypoole3906]

nice vid but wear some eye protection.

[@randall.chamberlain]

Forgot the barefoot

[@jupa7166]

A młotek i pręt do rozwalania pieca mieliście z poprzednich wytopów? 🤣

[@jeancollin8224]

Der Titel ist nicht korrekt. Eisen ist das Resultat der EisenERZverhüttung!

[@WildBearFoot]

What do you think that red powder they put in the furnace was, paprika?

[@MAKC_Seva]

They ruined the whole lawn

[@alauda525]

Кузнецы-колдуны, что с огнём играют🔥

[@erossutrisno]

the grass were ruined

[@ryangreen1588]

keeping it real medieval with lack of safety glasses lol...

[@randall.chamberlain]

Also barefoot :D

[@timhaakenson916]

IM DOING THIS TYPE OF SHlT ANYWAY

[@Ziom56_Raksek]

Polak potrafi

[@ericschmid]

I see an alarming lack of safety glasses! Hammering the molten iron.

[@officinaferraria]

Iron in this process is not molten.

[@mohamadourika4031]

👍🌹🌹🌹🌹💌

[@БаторДоржиэв]

С чужого видео копирует вор.

[@mustamuri]

🔥🍼🔥 👶👏

[@stephaneduena6177]

La flamme n'est pas belle

[@abdalrohmanmousa7405]

This is the worst kind of steal you could buy

[@pedrogarzagarciadetrevino9530]

Boring!

[@pinchevulpes]

Soy boy