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From Wrought Iron to Crucible Steel Knife

We converted wrought iron from old wagon tires into steel for a knife. To make steel, carbon needs to be added to the iron. We accomplish this by melting the iron in a crucible together with charcoal and special alloys. Wrought iron starts melting at around 2,800°F (1,538°C). The alloying elements came from O1 (Chromium) and H13 (Molybdenum). The total charge of the crucible was around 2000 grams. To be precise, we added 2006g wrought iron, 30g charcoal and 75g (O1/H13).

The firing time was pretty quick; around 30 minutes to get to temperature and then ramping it down for 60 minutes. The crucible cooled in the furnace for about 12 hours. We took it out at around 250F. Unfortunately, there were a lot of gas bubbles in the glass as well as in the steel. The carbon content was also lower than planned, maybe around 0.6% rather than the 1.5% we were aiming for. However, it forged very nicely and showed great carbides.

The experiment will likely show up as Forge Diaries: Episode 8 or as Wootz: Episode 6. Stay tuned.

How I got 5 Million Views on Youtube!

As of today, I have officially reached 5 million views on my Youtube channel. That seems like a large number for blacksmithing videos and something I never expected when I started documenting my exploits. So, let's take a look at the most popular videos.

In 2013, I made a knife for preparing Persian Kabab Barg. This video alone is responsible for almost 2 million views:

A year before that in 2012, I had started working on the Serpent in the Sword. A Viking-era sword with a pattern welded serpent at the core of the blade. At that point, I was also still learning how to mix audio; it was so bad I had to put up an audio remix. The Serpent in the Sword collection of videos accounts for another 2 million views:

At that point, I started spending much more time on video editing but never ended up with another really popular video. I found that pretty ironic. However, in 2013 John and I started experiments with making crucible steel which resulted in a knife with Wootz-like patterning. As of today, this video has a little bit more than one hundred thousand views:

Another video series which documents a complete sword build surprisingly only got a very few views. This is the sword I made for the ChronoBlade game. It was a lot of work and shows all sword making steps in detail but never really got popular.

Those are the mysteries of Youtube! Here is to another 5 million views.

Construction technique for a Pattern-Welded Wolf's Tooth Knife

Over the last year, I have been experimenting with different techniques for creating a Wolf's Tooth pattern similar to the famous pattern-welded spear from Helsinki. To keep track of the different experiments, I have literally kept a Forge Diary in which I document my different attempts. Here is what I believe to be the final potential construction technique for creating a Wolf's Tooth pattern.

The approach creates a sandwich of tool steel between wrought iron. To form the pattern, I forge grooves with a chisel on both sides which are roughly an 1/8in apart. I make a pass with the chisel in one direction to create the grooves and then go back the opposite way to open the cuts back up. After finishing one side, I switch over to the opposite side. Chiseling will cause the rod to bend, so it needs to be straightened occasionally. For this experiment, I used a discarded piece from a twisted bar of 1095 and 15n20. It was about 3/8in square. This is the size I use for all my pattern-welded rods. As you can see on the picture the cuts are not very deep.

After placing the tool steel between the wrought iron, I forge weld the pieces together and use a fuller to gain a little bit more width for the knife. Since I started with scrap pieces, I did not have a lot of extra material. For this experiment, I forged the cutting edge to final shape by the tang and let it grow thicker and less forged towards the tip. As a result, I needed to grind away subsequently more metal the closer I came to the tip. The reason for doing this was to visualize the progression of the pattern. Towards the tang the pattern should not be visible and by the time I reach the tip, the pattern should disappear as the outer wrought iron layer should have been completely ground away. The pattern requires that more of the inner layer is being exposed towards the cutting edge and less of it towards the back of the knife. I am thinking of it as taking a diagonal slice through the metal that reveals more tool steel towards the edge and more iron towards the back of the knife.

This worked out mostly but not quite. It was difficult to keep the tool steel exactly in the middle and I was also rushing the work as usual. While the pattern looks interesting, it is very unlikely that this technique was used for the spear. Nonetheless, it was an interesting experiment and the resulting knife is quite cute.

I am also somewhat curious about the origin of the term "Wolf's Tooth" pattern. I have not seen it properly defined anywhere and in German, I have seen it described as "gezackter Rand". If you have any insights into the term, please share them with me.

Anyway, this really is an entry from my Forge Diary :-)

Pattern-Welded Kurzsax

This knife is a multi-bar construction with W1 for the cutting edge and 1095 and 15n20 for the twisted rods. It is inspired by early Viking-age finds from Norway. The guard and pommel are made from brass and embossed with a triangle design. The handle is made from bok oak used in the defensive ring wall of the Viking-age Haithabu settlement in Northern Germany.

The knife was created as the result of an accident. While working on the rods for a Langsax, I twisted too hard and a piece of the rod sheared off. Fortunately, that piece was long enough to suffice for a Kurzsax. The blade is about 7.5in long and then handle measures 5.5in for a total of 13in. The knife features a scandi grind and is very sharp. There is no secondary bevel on the edge.