Pdwight
has rocks in the head
Member since June 2003
Posts: 619
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Post by Pdwight on Oct 11, 2007 16:35:38 GMT -5
ne ;
I was watching a PBS Special "Secrets of the Samurai Sword" the other evening. I have studied Iaido and the Japanese Sword for many decades (which just confirms how little I know.....the more I think about it) The show described the process of making the base metal for sword forging using Magnetic Iron alluvial sand . Now I have known this since Carter was the Pres. but now with the resources of the internet and this borad I would like to have a sample of this type of sand....anyone know of a source ??
Thanks Dwight
PS also facinating were the polishing stones which run thousands of dollars each and as many as 12 are required before you use the finger stones to begin the final polish.
Dwight
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rollingstone
starting to spend too much on rocks
Member since July 2009
Posts: 236
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Post by rollingstone on Oct 11, 2007 17:26:25 GMT -5
I could be mistaken, but I think this is just magnetite. When you pan for gold you end up with the heavy stuff left in your pan, which in these parts tends to be mostly "black sand" (magnetite) with a bit of flour gold mixed in. I've only toyed around with panning (ie done it once ;D), but I recall I ended up with a few grams of magnetite in the pan, with some specks of flour gold mixed in. I could use a magnet to separate the sand from the gold, but mostly I just played with pulling the sand up the side of the jar with the magnet. ;D I don't know of any commercial source, so that's not much help. -Don
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Post by docone31 on Oct 11, 2007 17:32:25 GMT -5
Dwight, Alluvial sand, go to the beach, stick a magnet in the sand, and there you have it. Way back then, the sword makers had a sand bank they took the sand out of. The main secret to the blade work is the use of charcoal. They would gather the sand and fire it in a reducing furnace. Each one made for one sword. The calcite in the furnace would combine with the sand while it was melting. The resulting glass would act as flux to seperate the iron. The molten iron would then be poured into seawater from a reasonable height. This would hard cast the iron, and sodium would be introduced to the casting. The next step would be to melt the iron and pour it into an ingot. From this point, it would be forged over the reducing furnace. The use of charcoal introduced carbon into the iron, and at the time, reduced the O2. As the billet was hammered out, carbon deposits would be hammered into the iron, beginning to make steel. As the steel was heated, drawn out, folded, heated, folded, layers would produce a damascus steel. Differing layers of hardness would be introductd into the metal. The folding produced more of a diffusion layering rather than an alloy. A diffusion weld was where the outer band of electrons would intersect without merging. The valance of the atom would also, then contain the other atom. This makes an harder bond than alloying. Where the molecules are contained by parasite holding. The molten sand was broken up as flux, and reheated untill it became so dirty it clogged up. The stones used, were imported stones. Each artisan had his own preference. It was usually handed down in the family. The final stone was the dust of all the stones bleached of the iron from the manufacturing of the blade. After heating, and bleaching, the stone dust was almost a talc type of material, it would absorb the moisture from the blade so clove oil could be applied. Basically, it is like our Arkansas stones. Only, each artisan would use one or two, then as each stone got smaller it would serve as fingerstones. They had corundum stones back then, and those stones did the larger shaping process. You can find Alluvial sand by digging down untill you find the sandy layer under the topsoil. They did not have any known iron deposits untill after the late 1880's. They got their iron from sand and the iron deposits within.
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stonesnbones
spending too much on rocks
Member since September 2007
Posts: 255
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Post by stonesnbones on Oct 11, 2007 17:52:53 GMT -5
I watched that last night,Dwight.Interesting stuff its been a while since I had read or seen anything about them.As a collector of militaria,I have handled my share of them and other blades.There is only one other that even compares to the samurai blade.
Brad
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Pdwight
has rocks in the head
Member since June 2003
Posts: 619
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Post by Pdwight on Oct 11, 2007 22:09:49 GMT -5
OK Brad , you cant make a statement like that and leave...you got to let us in on it :-)
I love edged weapons
Dwight
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Post by invisibleuser on Oct 12, 2007 7:45:24 GMT -5
[quote author=docone31 board=general thread=1192138538 post=1192141945 As the steel was heated, drawn out, folded, heated, folded, layers would produce a Damascus steel. Differing layers of hardness would be introduced into the metal. [/quote]
"Damascus steel has a band structure quite different then that of a samurai sword, although the idea of combining hard material and tough material is similar. It just happens at a very fine scale in the Damascus steel rather then in two distinct pieces. A similar layered structure can be made by folding two different grades of steel together but this is reportedly not the original method of manufacture" (Richard P. Vinci)
Steve
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Pdwight
has rocks in the head
Member since June 2003
Posts: 619
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Post by Pdwight on Oct 12, 2007 21:39:17 GMT -5
True , a high carbon steel outer core (around 1% Carbon....quite high) was supported by low carbon inner core. This gave it the ability to hold a great edge and still be felxable. I have seen this first hand with one of my Japaneese swords that was straightened...I would have never thought it would take that much bend and not break. A device kinda like a mitre box is used to hold the sword while it is bent.
Dwight
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Pdwight
has rocks in the head
Member since June 2003
Posts: 619
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Post by Pdwight on Oct 14, 2007 16:04:04 GMT -5
A lot of research has been done on Japanese Edged Weapons. Lots of broken swords and Yari, Naginata etc have been analyzed and all are remarkably similar in metallurgical properties. Almost all outer cores are at 1% carbon or very...very close. This is pretty remarkable due to the fact that they had no method of measuring the mix, only experience and following a formula that worked for hundreds of years.
Dwight
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Post by Original Admin on Oct 14, 2007 16:18:06 GMT -5
Its good to see you back here doc.
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Post by snowdog on Oct 15, 2007 22:42:18 GMT -5
if your wanting some "blk sand" -- I've got some from gold panning -- ( just send the gold back since you don't want it ! ;D ) ------ was watching a film the other night and they showed how they painted the blade with a clay then "fired" it and when cooled it produced the "curve" to it --- was real interesting !
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Pdwight
has rocks in the head
Member since June 2003
Posts: 619
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Post by Pdwight on Oct 15, 2007 22:51:17 GMT -5
I would love some black sand...PM me if you are serious.
Dwight
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