Smelting Experiment

Forging, smelting, bronze, silver, gold smithing....

Smelting Experiment

Postby Dan_Dalby on April 4th, 2013, 12:53 pm

Hi all!

My group, Project Germani, attempted to smelt some bog iron two weeks ago, and we posted a video on YouTube of us doing it!




We did get a bloom out of the furnace, but it was too thin and brittle to work (also, the iron had too much carbon in it, making it very difficult to work). Next time, we plan on using much less charcoal, as well as more powerful bellows to create an even distribution of heat in the furnace. Still, I feel it went fairly well for a first try: we actually got the bog ore to form into iron (we demonstrated this through magnetic testing).

Dan
Dan Dalby

Group Leader of Project Germani

http://www.projectgermani.org/

https://www.facebook.com/pages/Project- ... 72?fref=ts

Sigaz ar Dauthaz!
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Re: Smelting Experiment

Postby Pat Leppan on May 6th, 2013, 9:20 pm

In some of the smelting videos I have seen, once they got the bloom out and reheated, they struck it either with rocks, or used a wooden board to soften the blows to the bloom so as to avoid shattering it. I doubt that this was at all a factor in your process, but if you get a larger bloom next time that might be a nice precaution to take to avoid breaking the bloom into fragments.
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Re: Smelting Experiment

Postby Jose Miguel on July 26th, 2013, 3:11 pm

Hi boys!

First of all, I would like to congratulate you for the experiment. Really, it's not easy to get iron experimentally. There are a lot of elements that can affect the result of the reduction in a low shaft furnace assisted by bellows... the quality of ore and charcoal, the air volume of the bellows, the ratio ore/ charcoal, etc...

Magnetic slag doesn't mean that you get iron. In fact, many times it happens when roasting the ore that it becomes magnetic.
Can I ask you how many kg. of charcoal and ore did you use? How many time did you use the bellows? How many time did you pre- heated the furnace?

I think you may probably will know this. It's an experiment made in the year 2000 in Southern France.

http://www.canal-u.tv/video/universite_ ... ubois.4336

There is also an excellent iron- maker from Holland. You can see him here:

http://www.youtube.com/watch?v=Y_mTgHj6M1Q
http://www.youtube.com/watch?v=URxbEQs98Go
http://www.youtube.com/watch?v=gjManty8sQg
http://www.youtube.com/watch?v=J7nzmhFwGoM

Best regards
J. M. Gallego Cañamero
www.artifexcrpa.com
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Re: Smelting Experiment

Postby Dymphy G on December 2nd, 2013, 10:21 am

I saw something on a particular viking sword, it was called something like umberth. It was a documentary with an US smith trying to recreat it. He had a particular way of melting the iron. Anyone knows what I'm talking about?
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Re: Smelting Experiment

Postby jackmcauliffe on November 22nd, 2015, 2:23 pm

So less charcoal will not inherently give you less carbon in a bloom. I think it's unlikely you produced cast iron or super carbon steel. More likely it was unable to form into a bloom due to too much slag, not enough air pressure, or improper ore roasting. What was your descent time and what was your ratio charcoal to ore?

As for the ulfberth sword. That is a crucible made steel. Also known as wootz it is make in a different furnace and has a completely different chemical Makeup to bloomery iron. Nanotube dendrites etc etc. But it originated probably western India. Around the 7th-8th century it reached Northern Europe I beleive but don't quote me on this part. really great stuff but a pain in the butt to forge since you have to baby it at low temperature and it's tough as heck.
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Re: Smelting Experiment

Postby jackmcauliffe on November 22nd, 2015, 9:31 pm

Hi again, so I got a chance to watch the results and such from your video and I have a few more tips if you like.

Your stack is too short for a smelt from ore. It looks like you guys built a remelting hearth furnace for recycling iron. The purpose of the hearth is the consolidate small irony bits and can also add carbon to make food steel. Rough dimensions for a proper smelt of this period is 3-4 feet high by about 8-10 inches (sorry to use imperial measurements).

Stack hight is crucial for reduction and preheating of ore. Even though it's been roasted and broken up, I assume, it has to descend down the furnace as the charcoal burns to prepare to seperate iron from slag. A good rule of thumb is 10 inches every ten minutes.

It appears as though your results are actually just slaggy blobs, I've gotten the same result dozens of times. I've usually found it to be the result of poor charcoal and improper air Pressure or it could be the tuyeres angle. Sometimes you just have to play around these things if you are not building a stack of someone else's demensions. It's very unlikely you got High carbon steel or even cast iron directly from ore. Also like I said it is not the result of too much charcoal, it's about the burn rate.

Either way, great job I hope you do more because this is great. I love the dedication to people who want to smelt and do it right! Good luck further on.
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