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X-san
3rd February 2005, 21:48
Given that I live on a farm, I have a few unusual training opportunities. I decided to try something unusual today and practiced striking hay bales with my bokken, and found a strange effect. A hay bale struck with the tip of a bokken will dent slightly and bounce a bit, but I can make a larger and deeper dent by simply striking the bale with a hammer-fist strike, or by striking slowly with the first third of the blade.

Now, simple physics or the most elementary experiments will show that a lot more force gets generated at the end of a sword than near the guard. Thus, either I'm not generating very much power at the end of the sword for whatever reason (unlikely), the energy is being wasted somewhere, or it's all going deep into the bale instead of being spent making a dent given the speed with which the strike is delivered. As the bale seemed to bounce and shake as a whole after struck with the tip, it seems that the latter conclusion would be correct.

Opinions? All of a sudden getting one's bones broken by strikes with a bokken or staff seems much more likely than it had to me.

nicojo
3rd February 2005, 22:12
Oh, I thought this was going to be about when I got to be a jedi.


or it's all going deep into the bale instead of being spent making a dent given the speed with which the strike is delivered. As the bale seemed to bounce and shake as a whole after struck with the tip, it seems that the latter conclusion would be correct.

Yes I think you are right. A different effect might happen if you have a bokken with a sharper kissaki (not sharpened, but narrow if you know what I mean). But bokkens in general have that blunter tip so the "force transmission" would be different from a sword. Smarter and more experienced minds will no doubt speak, but I think the concussive potential is still there even with a shinken tip however, meaning a bone could be bruised/broken under the cut if the sword did not cut that deeply. But this is obviously beyond my experience so I'll shut up now. :D

Now I will take my bokken to the Wyoming ranch when I visit my dad. He will probably make me cut hay first though.

edited to say--with a swather, not a shinken!

Eric Spinelli
4th February 2005, 21:42
Opinions? All of a sudden getting one's bones broken by strikes with a bokken or staff seems much more likely than it had to me.

You can break bones with a punch or a kick. Without going into the physics, placement/angle has as much to do with transmission of force, but it is possible with most anything. Yes, certain bones like the femur have the equivalent strength of concrete, but even concrete is brittle and cracks and small enough pieces can be broken with the human body.

Most Japanese weapons include edges for ease of use and to cut through armor, not because the weapon is ineffective without one. Most combat techniques delivered properly to the appropriate target would most likely incapacitate or kill the opponent - the edge is there simply because of the stress and difficulty of inherent completing the perfect technique in a battlefield situation. A jo tsuki (thrust/stab) to the solar plexus or jaw will cripple as much as spear tsuki. The fatal targets simply increase with puncturing capabilities. Imagine the same for a bokken and shinken.

I suppose that doesn't answer the question, but I don't care.

X-san
5th February 2005, 02:01
Hey, friend, just talking about something weird I found. I was apparently under the impression that striking with the tip will produce the most energy upon impact based on tip speed alone. Of course, it's not that simple and many factors come into it.

http://www.thearma.org/spotlight/GTA/motions_and_impacts.htm

This article was particularly helpful in clearing things up.