Shear Steel; The Experiment Begins

[Joshua States]

Back to Will's project....

On ‎5‎/‎19‎/‎2018 at 1:27 PM, Will W. said:

Any thoughts, comments, or critiques on the design are welcome and encouraged. 

I was waiting for one of the seax enthusiasts to lend a suggestion, but that does not seem forthcoming. So, I will give what meager advice I can muster.

First off, review everything here and here for the geometry, both the blade and the handle (both appear not-quite-right to me). There are plenty of examples of war knives and early seaxes in both threads, originals and reproductions. Rather than putting a new design on a very old one, I would suggest you try to replicate what the ancients made.

Your handle is atypical from what history has shown us these blades' handles were like. Your handle design is more like a modern-day survival knife with those finger grooves, and to be perfectly honest, it looks like it would be dreadfully uncomfortable in the hand. 

Lastly, here is a link to a powerpoint presentation by our esteemed historian Jeroen Zuiderwijk. https://drive.google.com/open?id=1QQ4NLkfXFWwMeYxNq-dCa81iDRbpdo7T 

 

[Will Wilcox]

Awesome video, very informative. Thanks for posting it, Joshua.

I would imagine that the steel casing in Kevin's video is also now of a higher carbon content then what it began as, on the inside, obviously. To what degree, if any, i would be interested in knowing.

Curious now as to whether using lab grade chemicals in both samples would have yielded more similar pieces of steel. 

Also curious as to whether a clay casing vs a steel casing would have any noticeable effect on the blister steel. Perhaps the tubing he used robbed some of the carbon away from the wrought iron? Theres so much room for experimentation here!

Rambling aside, thank you for being honest about the design as well, i agree, its pretty awful lol. It was kind of just something that looked good in my head, but came out terribly on paper (like everything i try to draw, essentially .) The grooves were supposed to be smaller, not necessarily for finger grooves. 

I do still want to do a seax of some sort when (if) this project reaches that point. Ive never made one, and i think it would be a historically appropriate goal for this project. Not knowing a whole lot about seaxes, i appreciate the links for more info. I will be reading up on them for sure.

[Emiliano Carrillo]

Sometimes it can be hard to translate what a rusted museum piece and a 'new' seax have in common. I recommend checking out George Ezell, Jeff Helmes, Owen Bush, and Jeroens presentation which was linked above! They all make work that is very authentic, and will give you many ideas about what your end goal may look like if you want to make a seax. I'm working on a large war knife type seax similar to what you described in your post a while back as well. I base everything I make on study of the old stuff! There's a plethora of modern makers that can inlay and pattern weld like no ones business, but there seems to be a lack of people who really want to research the old blades before making what they call a seax. You're making your own steel for this experiment, and I think you'll regret it if you don't do more research to come up with something that you really like first! 

 

Then again, you can make a modern fantasy knife just as easily, it depends on what you want to make! But I would urge you to research heavily if you want to make a real seax! 

[Will Wilcox]

Emiliano,

The whole idea behind this project is to follow in the footsteps of the ancients, and do as they would have done. So a more historically authentic leaning piece is definitely the end goal. I have some needed research ahead of me, for certain. 

Not only this project, but just in general, i like to try to replicate the old ways, make my ancestors proud  lol.

I agree with you, the amount of time and energy it will take to see this through, a solid design and execution is almost necessary. 

Thank you for the advice. 

[Richard Furrer]

last batch of blister I did.

25 pounds pictured...the rest was used for projects.

Note the late blisters vary with heat....sort of a Goldilocks with too hot and too cold and just right. Hard to rotate a 45 pound billet to even things out.

 

My suggestion for making blades is to do a test knife from the billet to check heat treatment and then do the main project. Not only is wrought iron variable, but the carbon diffusion can be tricky in shear steel form. I suggest at least three fold welds to both refine the "grain", but also to allow time to even carbons levels.

Ric

Edited December 13, 2018 by Richard Furrer

[Conner Michaux]

What is shear steel? Lots of people post about it but I still have yet to understand it.

[Richard Furrer]

when you weld up a stack of blister you get shear...further welding is double or triple shear.

 

[Alan Longmire]

1 hour ago, Conner Michaux said:

What is shear steel? Lots of people post about it but I still have yet to understand it.

Refined wrought iron that has been carburized as shown in the video becomes blister steel, Ric explained the rest.  

[Joshua States]

1 hour ago, Conner Michaux said:

What is shear steel? Lots of people post about it but I still have yet to understand it.

There is a video on page 2 of the thread that pretty well explains the blister-shear process.

Alan beat me by that much.

Edited December 14, 2018 by Joshua States

[Will Wilcox]

That sure is a lot of the stuff you made, Ric! 

Thank you for your input, i appreciate it, and will keep it in mind when this project progresses.

Any idea on what carbon % your steel turned out to be? Even a rough estimation? Im simply curious. 

[Richard Furrer]

Made these videos a while back :

 

 

[Alan Longmire]

AAAAAnd we're pinning this one.  Thanks, Ric!  Those were great videos!  

[Will Wilcox]

Thanks for posting the videos Ric, i will definitely be watching them when i get home from work. 

And thanks for the pin, Alan. Now the pressure is on to actually make some steel, eh?  Lol.

[Joshua States]

22 hours ago, Richard Furrer said:

Made these videos a while back :

Yes indeed. Thanks Ric.

[Fox Creek]

On ‎4‎/‎28‎/‎2018 at 7:02 AM, Alan Longmire said:

oth processes also recommend leather and bone charcoal as better than wood.  I have heard all sorts of explanations, ranging from phosphorus and potassium in bone promoting faster carburization to the black magic of using animal parts to the (more likely) it was a good way to use the byproducts of butchering.  Commercial carburizing compounds contain barium, and I have no idea why.  Plain old wood charcoal is fine.  Carbon is carbon, but I doubt diamonds make a good carburizing compound...

Alan, I imagine that the barium acts as an "accelerant", optimizing carbon transfusion into the iron.  Lots of old shop manual recipes called for adding calcium carbonate to the mix as an accelerant, but I believe this was a red herring and a mistaken shop tradition.

[Alan Longmire]

Good to see you back, Richard!  And I think you are right.

[Jerrod Miller]

The ASM Heat Treaters' Guide (referencing ASM Metals Handbook, Heat Treating, Vol 4, 10th Ed., ASM International, 1991, p. 325) says:

"Pack Hardening

In this process, carbon monoxide derived from a solid compound decomposes at the metal surface into nascent carbon and carbon dioxide.  Carbon is absorbed into the metal; carbon dioxide immediately reacts with carbonaceous material in the solid carburizing compound to produce fresh carbon monoxide.  Carbon monoxide formation is enhanced by energizers or catalysts such as barium carbonate, calcium carbonate, potassium carbonate, and sodium carbonate present in the carburizing compound.  Energizers facilitate the reduction of carbon dioxide with carbon to form carbon monoxide."  

So, both barium carbonate and calcium carbonate are good to use when trying to add carbon to steel via diffusion.  

[Will Wilcox]

A summer's worth of trials with the river clay. And a summer worth of failures. I cant seem to make anything that will survive heat. I believe this is because of my firing setup.

 

I'm going to try using a pit furnace next, instead of an exposed fire pit. I think the inconsistency of the heat is my downfall. Just need to figure out how to get some consistent airflow going into a pit. And I need to get it done before the ground freezes .

 

Just figured I would give an update, I've not abandoned this yet .