Bloom iron

cangooner

New Member
I know Bruno started a thread here last year about making bloom or crucible iron, but I'm wondering if any of you have experience to share forging it? Specifically in my case bloom iron. I have a hunk of it I ordered from Lee Sauder (https://www.leesauder.com/bloom_iron.php ) and hope to start playing with it in the next little while. No idea whatsoever about what it will be made into, but if all goes well, I'm thinking it would make for interesting knife spines.

Step 1 will be a slow and HOT consolidation process. Beyond that... open to suggestions. :)
 

cangooner

New Member
I have some experience. What Lee makes is iron, not steel. As long as you know this caveat emptor.
Yup - that's why I'm thinking of using it as a spine if I can get it to weld properly to blade steel. If that fails, then I guess I'll be making some decorative stuff. :)

Thanks very much for sharing that video - I would love to take part in something like that some day. How long did that process take from lighting the fire to retrieving the bloom?
 

Mike Blue

Member
A good stack furnace like shown in the video works best when allowed to dry. We accelerated the process by slow cooking overnight as the humidity in Tennesee was higher that day. In spite of the drawbacks, we still got a 63 pound bloom. About the middle of the video, you can see Skip Williams hammering to break up the bloom. The whole time he grumbled that the carbon content was going to ruin the bloom. I usually tell people it takes 3 days. The entire burn sequence started early in the morning about 0600 and we finished after dark about 2000. Most of it was allowed to cool down overnight and it was still hot enough to give pause when we broke down the clay stack.

But, I intended to make tamahagane, about 1.5% carbon steel. Spark testing was very pretty. Not all of the bloom will be good steel. This is the reason for so much folding and welding...to homogenize the variety of carbon contents in the parts of the bloom. Folding and welding is not magical or mythological or mysterious, it's very much like mixing ingredients in the flour before making a loaf of bread. In fact, the metallurgical Japanese language uses terms like "kneading" to describe this process. The process I learned was from a Japanese High School website. Later I was fortunate to meet Akira Kihara, the master smelter from Shimane. He liked my steel. I am satisfied with that credential.

There has been a debate among bloom makers about the benefits of carbon content. This process, whether iron or steel, is merely the control of time at temperature. Williams and Sauder always complained about too much carbon in their early blooms because they did not understand this. It would be interesting to see pictures of your piece spark tested. That will tell me a lot about what the other faction has learned. Then I can offer better advice.

As a quick alternative to your desired spine...lurk around some old metal yards and see if you can find some largish anchor chain links, especially the kind with a bar welded into the middle. These are probably really clean wrought iron. As a welded spine, when etched, it will have a cool looking grain of it's own. Plus someone has already taken the trouble to make the iron properly and save you a lot of effort. LOL
 

Bruno

Administrator
Staff member
Very interesting topic.
In fact that is one of the problems with this hobby. There are too many interesting topic to dive into each on of them. :)
Please update with pics on your forging experiences with this bloomery iron.
I have some bloomery steel I want to play with at some point, and very interested to see this happening in order to learn from it!
 

32t

Member
Very interesting topic.
In fact that is one of the problems with this hobby. There are too many interesting topic to dive into each on of them. :)
Please update with pics on your forging experiences with this bloomery iron.
+1
 
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