John C. Campbell Folk School
Sword Class 1999
The sword class this year was excellent. We followed the format of the previous years and after settling in to the work stations everyone forged a sen from leaf spring. The sen made were very similar in shape and size to the one pictured in Yoshindo Yoshihara's book Craft of the Japanese Sword The sen is a scraping tool and the most effective ones made were flat on the back with a rolled edge on the top side. After a few trails, the most effect bevel was found and they were pulling shavings off the forged blades.
The forging went well and everyone in the class was able to forge a blade. Many students brought new hammers and it was necessary to grind in the faces to get them to strike without marking and leave a smooth flat surface on the blade. The most difficult skill to learn was to forge bevels on both sides of the blade equally. The technique that I taught was to first forge a mini bevel on the edge, making sure that the bevel was equal on both sides and centered on the bar. This mini bevel gives a reference point when you begin to forge the main bevel and shows you where to hold the bar on the anvil to keep it centered. It is a bit confusing at first, but once you get use to it, it really is an efficient way to work.
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After the blades were finish forged, we cycled them in the long forge three times bringing them up above critical and allowing them to cool between each cycle to black heat. Then the shaping began. The sen is a hogging tool, but it takes some getting use to before it can be used efficiently. If you are too aggressive with it and not careful to watch how it is cutting, it tends to work harden the surface of the blade and made hard spots that will skate a file. The blades then have to be reheated to soften. After shaping with the sen, we move to files. Each tool requires the right touch and while the sen must be used with quite a bit of pressure, draw filing is a much gentler action. You should be able to carry on a conversation without losing your breath while doing it.
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