A question about sori

[16k]

Hi folks,

 

Yesterday , I was reading one of Markus’ Kantei supplement and he was talking about the Sori of a sword and suddenly, a question popped into my mind.

 

Now, being completely self taught about swords and only following books as mentors, I’ve been taught that you measure sori from the mune machi to the kissaki and it gives you both the nagasa and the sori.

 

Of course, it works great for ubu swords, but what about suriage and Ō-suriage swords?

 

I’ve been doing it the same way for years, but wouldn’t it be more accurate to measure the sori not from the mune machi but from where the original mune machi was supposed to be if it can be determined?

 

This way, it would give you a better idea of what the original sori was and also a better way to imagine the original sugata and thus, a sense of the age of the sword.

 

I may be completely wrong here, or on the contrary stating an evidence, but I don’t think I’ve ever seen this pointed out in any books I’ve read.

 

So to sum up, should we calculate sori the same way between an ubu sword and a (greatly) shortened sword?

 

Sorry (sori?) for the stupid question

[vajo]

Hi JP

the sori didn't change by suriage and o-suriage swords. Only by machi-okuri. They cut only the nakago.

 

I don't know if I'm correct.

[16k]

Okay, Chris, i guess I should have added machi okuri!

[vajo]

If they cut a tachi from 82 cm nagasa to 60 cm by machi okuri it would be diffcult to know what shape it was before.

[16k]

True, but then, the curvature continues into the nakago, so shouldn’t that be taken into account to know wether the sori was torii, koshi or saki?

[vajo]

Tachi have a deep sori near the nakago. So it is impossible to follow the curvature i think.

[16k]

Okay, thanks for the clear answer. Cheers!

[Rivkin]

The big problem will be that sori is non-uniform. Old blades, up to Nambokucho blades can appear almost straight when severely cut down, and "extending them where they should be" is rather complex - especially since these cut-down forms were extensively copied at later times, or accidentally reproduced (cut down Oei can be a close match for cut down late Kamakura).

 

Just a personal take.

 

Kirill R.

[SAS]

I see the point of your question, but how do you measure something no longer there? Useful for visualization exercise but the sword is still what it is.

[16k]

Actually, that was why I asked the question. You read stuff like “this school usually forged a koshizori” but when you’re in front of an Ō-suriage, machi okuri Blade with almost no sori left, it’s extremely hard to imagine the original sori. An ubu blade is relatively easy to date, others can be a real challenge as sugata has been altered so much that you’re only left with the other Kantei points to come to a conclusion.

[Ganko]

Seems to me that the sori would no longer be relevant in determining the time period  of an O-suriage sword. Who knows where the original machi was? Kind of difficult to extrapolate it out. Just an educated guess and conjecture IMO.

[16k]

Well, many times, the lowest mekugi ana is the first one. Then it’s not too difficult to extrapolate (the three fingers empirical rule) where the first machi was

[Dave R]

 That presumes that the "new" nakago follows the line of the the old blade.... It may very well be heavily reshaped.

[Jussi Ekholm]

I think you are asking really important question JP and that is one important aspect of kantei that you try to use your knowledge to try to "see" the sword in original form.

 

The sword (bare blade as whole) is called tōshin that includes the blade & nakago. While sori is used for curvature between munemachi and tip of kissaki there is also nakago-sori that can be measured. I wish I would be good at drawing it would be easier to explain than with words. But at least I tried to make a few pictures. Of course the scale of those is bit off.

 

Different sori and nakago-sori will have a huge effect on the overall sugata of the sword. When you calculate blade curvature you can take two measurements. Regular sori and also from the butt of nakago to the tip of kissaki. With swords of very large nakago curvature this will of course produce large overall curvature to the sword even if the sori is small and vice versa swords with very big sori but small to none nakago curvature will not produce a pronounced difference when measured like that. The name for measurement from nakago butt to tip of kissaki is called zencho 全長 but I am not aware what the full length curvature measurement is called. But here is a picture showing how shortening will also affect sori as measurement point moves upward and it affects the overall curvature even more. I tried to fit in my drawing that when shortened enough neither of the holes remaining is the original one as it has been lost with the signature.

 

 

One thing that I feel is important when it comes to shortened swords that you search information how are the surviving swords in original or near original length made by that smith/school. Yes for some there are very few if any references left but it is very valuable information. Also you can find examples that vary a lot within the works of the same smith.

 

I have so many things about this subject running in my mind I can't really type it out as an easy post. I've drawn just for fun some full sized sword pictures up to scale, might be fun to make 1:1 picture for example 90 cm tachi that goes through few shortenings and ends up as 65 cm katana. I know you can make up stuff like this in photoshop etc. but I think it is nice to have 100% sized picture in front of you. And of course I can spend that time studying swords while I am drawing.

[Ken-Hawaii]

A good part of kantei is being able to do the visualization of the original blade. Good drawing, Jussi - it should be helpful to many.

[Vermithrax16]

Wow Jussi, nice way to show this thought process.

[Ganko]

Nice drawing Jussi. As can be seen from the picture any shortening will always reduce the value of the sori  and in some cases can change the point of maximum sori to a much different location.A large amount of shortening could turn a koshi- sori piece with fumbari into a tori-sori piece or turn a saki-sori piece into more of a tori-sori. If one is going to use the sori value to make comparisons for kantei purposes, you need to know where the machi was with a high degree of certainty. Fortunately most blades are not shortened to the extent where it would make too much of a difference and it is a useful kantei factor.

[16k]

Jussi,

 

You’ve put into drawings what I actually have in mind.

 

I have a Muromachi Soshu Blade that is torii sori. Yet, when you hold it in front of you, bare, you’d swear it is a koshi sori. Obviously, it was a tachi in another life that got greatly shortened and machi okuri subsequently. If I take into account the nakago, it becomes koshi sori. So I guess that taking the nakago into account is a great way to imagine what the blade used to be.

 

Now, there are pitfalls here! But I’m pretty sure this way of thinking is helpful in getting a further notion of the original sugata.

[Jacques]

the right term is suriage (O-suriage) and machi-okuri when a nakago is cut partially or entirely cut down. The term machi-okuri alone is used when machi are moved up on an ubu nakago.

[Jacques]

.

 

 If I take into account the nakago, it becomes koshi sori. 

 

 

Usually Soshu swords are tori-sori, koshi-sori is found on old blades (late Heian/early Kamakura) also in Bizen den.

[vajo]

I tried to fit in my drawing that when shortened enough neither of the holes remaining is the original one as it has been lost with the signature.

 

One thing that I feel is important when it comes to shortened swords that you search information how are the surviving swords in original or near original length made by that smith/school. Yes for some there are very few if any references left but it is very valuable information. Also you can find examples that vary a lot within the works of the same smith.

 

I have so many things about this subject running in my mind I can't really type it out as an easy post. I've drawn just for fun some full sized sword pictures up to scale, might be fun to make 1:1 picture for example 90 cm tachi that goes through few shortenings and ends up as 65 cm katana. I know you can make up stuff like this in photoshop etc. but I think it is nice to have 100% sized picture in front of you. And of course I can spend that time studying swords while I am drawing.

 

Hi Jussi if you allow i bring your drawing on a white paper. If someone will print it for studying. 

Thanks for your work.

 

 

Best

Chris

[Surfson]

One approach that I take is to follow the shape of the shinogi line in the nakago.  Often when a sword is shortened, they shave it on the mune side as well to make the new nakago more straight in the handle.  If you see the shinogi moving toward the mune in the nakago of a suriage or osuriage sword, it can be an indicator of some curve that appears to be lost.  Of course, in much older swords it is often the case that the shinogi isn't present in the original nakago....