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