seven star duan jian with bend

Sword typology and Edge Weapons forms of the Chinese Empire and related cultures with an emphasis on their relationship to Swordsmanship.

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josh stout
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seven star duan jian with bend

Post by josh stout » Tue Mar 06, 2007 1:04 pm

This is a picture of a duan jian I got for a student recently. I could tell the guard had been replaced with iron, but it all looked nice and solid and good to practice with. When the sword arrived, the blade had a slight bend in it. It was not the usual and fixable bend from side to side, but one in the same direction as the edges. You can just see it in the picture.

Was this bend intentional and some sort of custom design for someone's personal sword? Was the bend a mistake in the quenching process? Or, as is most likely, did the sword get bent with use?

If the blade bent with use, is there any way to straiten it?
Josh

http://s77.photobucket.com/albums/j65/p ... esfiRP.jpg
hidup itu silat, silat itu hidup

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josh stout
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Post by josh stout » Thu Mar 08, 2007 11:05 am

I just wanted to make the brief comment that when thrusting with this sword the curve is situated so that a thrust with the edges oriented vertically is more powerful than if it were done with a perfectly straight sword. The Indonesian pedang larus makes use of a similar shape.
Josh

http://i77.photobucket.com/albums/j65/p ... ion052.jpg
hidup itu silat, silat itu hidup

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Peter Dekker
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Post by Peter Dekker » Wed Mar 14, 2007 11:23 am

Hi Josh, I don't quite know what to make of it. Does the place of bend, or an area near it, show signs of excessive polishing as if a nick was polished out?

If it were caused by use I'd think it must have done some damage on the edge, too. I have a 17th century jian blade with a similar "bend" in it that I also expect to have been caused by use.

I recently also saw a dao with a sudden forward bend, but the bend was right above a very prominent nick. Still the integrity of the dao was pretty sound, it still appeared serviceable in a fight.. Some of that old steel surely is some tough stuff.

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josh stout
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Post by josh stout » Tue Mar 20, 2007 9:59 am

There are no obvious signs that the bend happened in one traumatic event, but general indications of a long period of active use. It could be that the bend happened over a long period of repeated use where the owner always held it the same way. As you say, the steel on these pieces is tough and tends to bend instead of breaking; still this one seems a bit unusual. Also the bend is conveniently useful.
Josh
hidup itu silat, silat itu hidup

-Suhu

Philip Tom
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edge-to-edge bends in blades

Post by Philip Tom » Thu Jun 07, 2007 4:23 pm

If a blade bent in this way due to a traumatic stress, you would usually see some side-to-side distortion (such as twisting or kinking) to accompany this effect. Over the years as a sword polisher, I have seen a couple of saber blades that had slight "inch worm" bends, usually at/near the center of percussion. Besides the slight lateral distortion there were also nicks on the edge right at the bend. In the past, my colleagues in this trade have also shown me one or two Japanese blades (usually the longer, narrower tachis) that were bent in a similar way. Straightening these can be a difficult process.

More often, I have seen jian with a slight, saber-like curvature in the blades. These are not always accompanied by nicks or kinks that suggested that someone tried to whack a telephone pole in two in one swipe. So it suggests that they were made that way.

I've talked about this with some of my "katana kolleagues" and they say that this is seen on some Japanese "ken" swords as well. Seems that heat treating double edged straight blades so that edges are hard and center is soft is kinda tricky, if the control of heat or the timing of the quench is a little off, one side will tend to shrink and the other expand, and voila! you get a bend. In most cases, it's so very slight that the polishers can correct for this, but if it's severe enough, it will be noticeable.

A guy who trained in San Soo "kung fu" told me that the slight curve can be used to advantage by a jian swordsman (I'm taking his word for it because I am not familiar with his school's techniques). It would explain why there is that small minority of combat jian out there that have this condition. If it were considered a fatal flaw by everyone, you'd think that none would leave the sword shop door.

Josh's comparison with the Sumatran 'pedang lurus' is most apt.
Phil

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