Safety in Training: The Iaito

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Safety in Training: Iaito Blades and Sword Training
by G. Hauenstein Sensei

Most people think that Iaito blades are safe. They believe that since they are not sharp that they are safer than Shinken (real swords). My premise is the exact opposite. I think Iaito blades are inherently more dangerous than swords for a number of reasons.

There are many types of Iaito blades available on the market today. Some are considered cheap "wall decorations" while other higher quality Iaito blades from Japan can cost over $1,000 dollars. Others are imitation blades made from 440C stainless steel and imported from Spain while others are sold as "collector" items through such places as the Franklin Mint. Why are these type of swords more dangerous than real swords? Lets examine Iaito blades and their usage in detail.

The first and foremost reason why Iaito blades are not safe is that they are not well made. The blades are made out of alloys or steel such as 440C stainless steel as mentioned above. The blades do not have the laminations or heat treatment that would make them structurally stronger, plus many are made out of some type of alloy. When a sword is swung repeatedly, it is subject to forces that can result in metal fatigue and stress cracks. This normally occurs underneath the habaki, the metal sleeve in front of the sword guard that locks the sword in the scabbard.

If you were to examine the metal underneath the habaki, chances are you would not see any cracks. This is because stress cracks are micro-cracks and are invisible to the naked eye. Techniques such as dye penetrant inspection or magnaflux inspections are required to see these types of fatigue cracks. Magnaflux inspection requires that a fluid be placed on the area to be inspected and then passed through a magnetic force field that causes the magnetic properties of the fluid to align themselves along the cracked area.

Dye penetrant inspection also uses a fluid to penetrate the metal and it is then passed under a blacklight which highlights the fluorescent qualities of the fluid that accumulate in the crack. The difference is that magnaflux is used to inspect steel and dye penetrant is used for any non-steel metal.

Because our sword cuts in Shinkendo are very strong, this is an area of particular concern. I have seen a high quality Iaito blade that was made in Japan snap in half during a diagonal cut. Luckily, no one was injured.

Cheness Cutlery's Deluxe Iaito made of Carbon Steel.

A tsuka (katana handle) with two mekugi ana (pin holes) and two bamboo mekugi (pins).

Source: jhbladesmith.com

Another consideration to think about is, how will the Iaito blade be used? If it is a style of Iaido that does not emphasize strong and effective cutting movements then perhaps a good quality Iaito blade well hold up well. On the other hand, if the style emphasizes strong, realistic cutting movements then consider these safety factors carefully.

In addition, the psychology of handling an Iaito blade vs. that of handling a real sword is worth mentioning. Practicing with an Iaito blade, although closer to being more real than a bokken, is still very different.

Watch a student who has been practicing with an Iaito blade pick up a real blade and start to practice. The focus, concentration and intensity of the student changes. The sword student now knows there is no margin for error in his or her movements.

Tozando's Toryumon Iaito made of Zinc/Aluminum Alloy.

Another myth concerning Iaito blades is that since they are not sharp they are therefore safe. The end of an Iaito blade is indeed sharp and could be very injurious if thrust into or through a person. The edge of an Iaito is not sharpened, but it can cut easily and effectively.

Think of it this way, an Iaito blade is a strong piece of metal that is moving through the air at a very fast rate. If it contacts someone accidently, they could be seriously injured. My Iaito blade is a top quality from Japan that has been in continuous use for over nine years. I have had it dye penetrant inspected and no structual cracks were found.

Recently, I conducted test cutting with my Iaito blade (yes, you read that correctly, see photo). I started by cutting dowel rods beginning with a 1/8 inch rod and worked my way up to a 5/8 inch dowel rod. That is over a half an inch in diameter piece of wood or about the size of an average index finger. By the way, there was no damage to the Iaito blade. So you can imagine, that if an Iaito blade can cut through a piece of wood that thick, what it would do to someone's body.

Another overlooked area of concern is the handle of Iaito blades. If they were made in Japan then more than likely the handles were made out of wood. Wood handles also need to be inspected for cracks. If a crack is found, then sometimes wood glue can be forced into the crack and the handle then clamped.

Other Iaito blades have handles of plastic. These types of swords are the wall decoration type of sword and should not be used for practice. For additional safety, the handle should have a second mekugi ana (peg hole) and mekugi (peg) added. The purpose of the peg is to hold the sword in the handle.

There have been accidents where a peg broke and the sword shot out of the handle injuring people. If you have only one peg, you start out with the peg being 100% strong and after continual use the percentage starts to derease. If you have two pegs, then you start out at 200% strength. Obviously, this is much safer. The size of the peg and what the peg is made out of is also important.

Many people use bamboo from chopsticks to fashion new pegs. Chopsticks are made from new bamboo which is not the strongest. The peg should be made out of the base of a stronger type of bamboo such as madake.

Sensei Butch (right) and son, Sensei James (left)