Anyone Have Long-term Experience with Japanese-Style Take-Downs?

[gregorio]

That style of mount works fine under reasonable use. The hard part is making it hold tight but still be reasonably easy to disassemble.

 

[KYJ]

First of all, I don't do I-ai(Japanese traditional martial art with sword), so I am not a Japanese sword user.
I like Japanese sword, and having been interested in for over 25 years.
So I write my "knowledge" not as Japanese sword user but as watcher.

Usually, Japanese swords owner will have Shirasaya(=Yasume-zaya: means strage or resting fittings).
It is plain wood handle and sheath.
Usually Japanese sword blade is kept in Shirasaya, with oil covering.
And when the owner use the sword, he(or she...) will set the blade in Koshirae(=using fittings).
It is the style which you would see as normal "Japanese sword".

But in ancient days, old Samurai must always has his sword as using style.
I believe that most of Samurais had only one or two swords, and he always kept having it.
Later, probably resting sheath was made first, and then, resting handle was made for sevaral swords owners.
Because the guarding oil is not good for the fittings.

In the Warring period, there was an Iron Mekugi, and also Nihon-Mekugi(two Mekugis style).
Japanese sword handle fits very tight...like Japanese style kitchen knife.
So the Mekugi is the secondary safety to prevent falling out the blade.
But in the Warring period, Samurais must fight against many enemies at a time, for long time without resting.
They could not be always keeping right cutting way, so the tension to handle would increase.
And it made loosen the handle.
For the situation, two Mekugi style or an iron Mekugi must be used.

I wrote as far as I know...and I hope that it helps you.
It's too difficult for me to explain in English...

 

[stezann]

Thank you KYJ, i didn't know 2 iron mekugi were used.
If i were to build one i think 2 mekugi style would be more difficult, because one of the mekugi would lessen the tension of the other as it would driving 2 wedges into one crack.

 

[JParanee]

most of my Japanese Swords designed for heavy cutting have two Meguki

I have a few Shiva Ki take down blades that only have one though

 

[Lycosa]

I'd use some kind of a nut and bolt mekugi.

 

[stezann]

The 2 mekugi construction may work and i'm sure it does if well done with a great deal of precision.
But if you think about it you would understand my concerns; that's it the mekugi is not a square precision dowel pin, but it is a wedge (a cone) which pushes against the back side of the tang's hole (a slightly oversized hole) and keeps the koshirae snug against the machi.
If we double it we need to be sure that either mekugi push the same amount simultaneosly, on the contrary one makes the other loose.

 

[Rick Marchand]

Great feedback so far.

Thank-you KYJ... you explained your thoughts very well. Excellent post.


I don't see a big problem in making a Nihon Mekugi system where the second mekugi installation tightens the first in the process. We'll see, I suppose.

 

[stezann]

Great feedback so far.


I don't see a big problem in making a Nihon Mekugi system where the second mekugi installation tightens the first in the process. We'll see, I suppose.

That's clever, thank you for opening my mind!! I didn't think of this possibility! Way to go :thumbup::thumbup:

 

[J W Bensinger]

Great feedback so far.

I don't see a big problem in making a Nihon Mekugi system where the second mekugi installation tightens the first in the process. We'll see, I suppose.

I think as long as the second mekugi by the pommel pulls the tang even slightly further into the hilt two will work nicely.
I forgot-I carried a parang of single (copper) pin construction as a ruck knife in the infantry-that thing got a beating (loaned out to 11B's for two years) and it never loosened up-the wood finally cracked about four years in-but i made that knife in about three hours and it was horrendously abused.

 

[islandblacksmith]

thought one:
there will be very different results and, therefore, different requirements for different use-cases...lorien hacks his way straight through the rainforest wherever he goes, but a small edc blade would not see near the shock as one of his tools does on a regular basis...for me the biggest "unknown" issue with such projects is sending carefully fit wood to climates that are vastly different...

thought B:
in the case of the nata mentioned, the heavy iron ferrule fits tightly against the top and bottom of the tang at the very front of the handle as well as snugly around the hardwood on the sides, i think this is an important design consideration that greatly increases the area of the transfer zone for the majority of the shock, taking strain off of the mekugi and the bottom of the handle...

fourth of all:
due to the long shaft and leverage, one of the highest levels of shock in traditional nihonto would be found in naginata or yari...these were typically mounted in heavy hardwood poles with iron ferrules and the full (long!) tang area protected and reinforced by an iron strip down each side, several iron bands, and a lacquer finish...

finally, and most importantly:
i think it is most important to study and understand the historical nihonto system as a complete package of components that all work together to provide the strength, longevity, and reliability it is known for historically...the core is a slightly softer shock absorbing wood (hounoki) which is carved very carefully to contact the tang at all points (rather than a few high points more susceptible to compression over time)...the back and especially the front of the handle core are held together by copper or iron caps (fuchi and kashira) to contain the stress of the tang...the centre of the handle is wrapped with rock hard rawhide rayskin (often lacquered for additional stiffness and protection) and then bound very tightly with cord or leather...the compressed seppa transfer pressure from the habaki to the face of the fuchi rather than allowing the full stress to come from the spine of the tang upwards...and with a proper taper angle the single bamboo peg keeps tension on the tang without loosening, compressing all the parts together...at 20x the strength of steel for the same weight bamboo is also chosen because even if it cracks it tends to stay in one flexible piece rather than breaking out as wood might...

_______

yes, single mekugi (or they will counteract one another...a second can only be a backup not an addition...make it thicker, not a multiple)...
yes, observing, studying, and working to fit things to tolerance levels we may have previously thought impossible...
yes, consider every detail an important product of centuries of hard field testing before deciding it can be left out...
yes, bring it into the present day and let's see what radness ensues!!! ...it is so nice to be able to field strip a knife when necessary...

 

[Rick Marchand]

Thanks for the well thought out, educational(and generous) post, Dave. There will be radness!

 

[Mecha]

Enlightening, illuminating thread. Thanks Islandblacksmith and everyone else. The brilliance and elegance of the Japanese hilt construction techniques have become ever more obvious over time as I study and ponder the system.

 

[islandblacksmith]

a couple of recent projects in this style...process photo essay here for the first one: bladeforums.com/forums/showthread.php/1320405-Fusion-Style-Kotanto-full-process-photo-essay...last one is inspired by the style of the indigenous Ainu people of northern Japan, the knife pattern is called makiri for you researchers...

...keep the radness coming!

 

[rustyrazor]

I've been toying with the idea of a steel push-lock pin with a ballbearing lock. can't explain it but i've seen it many times on armoured vehicles to hold down wire cutters and whatnot. that way the ball bearing detents go in past the tang and expand on the other side so if it does wear a bit, who cares, the bearings hold it in place and to remove it you simply press the button, releasing the pressure on the bearings and the pin slides right out. if done right it would sit pretty low pro and give plenty of wiggle room if required while still holding the blade secure

 

[Lycosa]

Thank you, Dave.
"If it works...
OutSTANDING work!!
rolf

 

[Doug C]

Rustyrazor,

Are you referring to ball locks, sometimes called quick-release ?

Doug

 

[Lorien]

thought one:
there will be very different results and, therefore, different requirements for different use-cases...lorien hacks his way straight through the rainforest wherever he goes, but a small edc blade would not see near the shock as one of his tools does on a regular basis...for me the biggest "unknown" issue with such projects is sending carefully fit wood to climates that are vastly different...

thought B:
in the case of the nata mentioned, the heavy iron ferrule fits tightly against the top and bottom of the tang at the very front of the handle as well as snugly around the hardwood on the sides, i think this is an important design consideration that greatly increases the area of the transfer zone for the majority of the shock, taking strain off of the mekugi and the bottom of the handle...

fourth of all:
due to the long shaft and leverage, one of the highest levels of shock in traditional nihonto would be found in naginata or yari...these were typically mounted in heavy hardwood poles with iron ferrules and the full (long!) tang area protected and reinforced by an iron strip down each side, several iron bands, and a lacquer finish...

finally, and most importantly:
i think it is most important to study and understand the historical nihonto system as a complete package of components that all work together to provide the strength, longevity, and reliability it is known for historically...the core is a slightly softer shock absorbing wood (hounoki) which is carved very carefully to contact the tang at all points (rather than a few high points more susceptible to compression over time)...the back and especially the front of the handle core are held together by copper or iron caps (fuchi and kashira) to contain the stress of the tang...the centre of the handle is wrapped with rock hard rawhide rayskin (often lacquered for additional stiffness and protection) and then bound very tightly with cord or leather...the compressed seppa transfer pressure from the habaki to the face of the fuchi rather than allowing the full stress to come from the spine of the tang upwards...and with a proper taper angle the single bamboo peg keeps tension on the tang without loosening, compressing all the parts together...at 20x the strength of steel for the same weight bamboo is also chosen because even if it cracks it tends to stay in one flexible piece rather than breaking out as wood might...

_______

yes, single mekugi (or they will counteract one another...a second can only be a backup not an addition...make it thicker, not a multiple)...
yes, observing, studying, and working to fit things to tolerance levels we may have previously thought impossible...
yes, consider every detail an important product of centuries of hard field testing before deciding it can be left out...
yes, bring it into the present day and let's see what radness ensues!!! ...it is so nice to be able to field strip a knife when necessary...

that is one damn fine post.

 

[stezann]

Agree!!
The Islandblacksmith posts the same way he works... there is so much we can learn!

 

[Lycosa]

This.^
And, thank you, to the makers. You make these blades to their utmost perfection.
rolf

 

[rustyrazor]

Rustyrazor,

Are you referring to ball locks, sometimes called quick-release ?

Doug

in fact i am. just googled the name... i think i can mill something similar if i can't find one that works and do it "low profile" enough to be unnoticable.