ROKUJURO

Possibly or even likely.

Brian, we have to imagine that a traditionally made sword-blade is basically a bonded sandwich construction in cross-section. The outer layers (= KAWAGANE) are high-carbon steel (hard, but not elastic, the inner part (= SHINGANE) is not hard but more elastic. If such a workpiece is bent, it will be stretched on the outer side of the bend, and the inner side will be compressed. The SHINGANE as the "neutral" part of the construction will stay in place under 'normal' conditions unless the item is broken. In a technical context, the phenomenon is well-known (tension side/compression side) and used in construction not only with metals but also with other materials like carbon fibre and wood. Just think of archery bows, boat and plane construction, race-cars and even modern bridges building. However, the necessary forces to stretch the metal are lower than to compress it, so long before compression ripples can occur, we will se microscopic rupture cracks in the stretched surface steel (= SHINAE). Now if we remember how we broke a piece of steel-wire as boys without appropriate tools ( perhaps old pliers ), we experienced that bending it back and forth weakend the structural integrity so much that it broke eventually. Using more speed, we even felt the generated heat in the wire! So bending back a bent blade could remain without visible and practical damage in case the bend was rather shallow. Also, depending on the physical features of and the steels used in a blade, a bend might occur at lower or higher stress impact. Thus, correcting a bend might have quite different results, and in case we see SHINAE, there will most likely remain a weaker spot in the blade even if the SHINAE could be ground out! My explanation for ripples in a BOHI or on a SHINOGI-JI is, as explained above, probably caused by a narrow MIGAKI-BO working on a not perfectly fine ground surface. If MIGAKI-JI is carefully executed in several steps, this could be avoided, I think, as we see on many blades. I would not consider the ripples as KIZU.

Jeremy, you may believe what you like, but in this case, the KASHINA sisters are plain wrong. SHINAE in whatever form are structural damage in the KAWAGANE.

Lou, as far as I know, there is no SASANO Museum, but a SANO Museum. Are you looking for this book: https://japaneseswordbooksandtsuba.com/store/book/fittings-books/b759-chic-sukashi-akasaka-tsuba-by-sano-museum/

Jeremy, MUKADE SHINAE are only a special form of massive SHINAE. In this case above, we don't see cracks but ripples.

Jeff, traditionally, when a sword suffered damage from use as on your blade, it was never left in that state for long! So if this happened in Japan, a TOGISHI was around the corner for a fast (and cheap) repair. We can assume this worked well until WWII. On the other hand, it is realistic (but admittedly not so romantic) to see the damage happen long after WWII simply because Japanese don't play with swords in such a way. Your TSUBA photo is upside-down.

From the scratch marks on the blade, I think it is quite obvious that they were not caused by "professional" TAMESHIGIRI (which is not executed on TATAMI but on TATAMI OMOTE which is a very different thing). These marks look - at least to me - as if they were inflicted to the blade by chopping or hacking green wood, possibly even green bamboo. I have only limited experience with classic TAMESHIGIRI, but I have seen comparable marks on machetes, KOSHI-NATA, Swiss "Gertel", and similar agricultural cutting tools after their use in the above described way.

No, they are close to the tip of the blade. The "end" is the NAKAGO.

As explained above, these ripples are not stress cracks, so not SHINAE.

Yes, KUNIYUKI. What is "old" in your opinion?

A "steal" band would not help, even not a steel band. As I wrote above, it is called KUCHI GANE (not fuchi gane), and it is made of brass.

Chris, are you aware what SHOSHIN means? By the way, it is not a KATANA but a TACHI as it is signed TACHI MEI.

Hi Jeff, correct, it is there. The photos are mostly bad, but they show a NIOI-based HAMON.

Jeff, now it is clear that the phenomena are not cracks or SHINAE. I have a question to another feature: Is there a real HAMON? Even in your magnified photos I don't see traces of NIOI or NIE. What kind of blade is this? Can we see the NAKAGO please (oriented vertically tip-upwards without HABAKI). So in case this was a machine-made blade, we could suspect the SHINOGI-JI was mirror-polished with a machine which would explain the above pictured phenomena.

Anthony, the KOGATANA is difficult to read. There seems to be more than only rust on the blade - looks like grime or paint. You can try to cleant the blade with acetone or paint solvent without any danger of damaging the steel. In case you will make new photos, please use a dark background and light from the side. And a remark on the characters: It is almost never a signature but a name of a famous swordsmith as an hommage.

Just for a better understanding I am showing some of my MIGAKI BO. I think they are made from a highly hardenable carbon steel, probably something like ball-bearing or so.

SHINAE are superficial cracks in the steel after a bend on the stretched side of a blade, and of course they are not beneficial to the structural integrity of it. What we see in Jeff's blade was correctly described as ripples, and they are something quite different. They can develop when the preliminary work in a BOHI left out a stage or two of fine grinding lengthwise which is tedious work. The final polish with a MIGAKI-BO 'compresses' the surface to a very small extent, and using only a pointed MIGAKI-BO can then produce these ripples. With differently dimensioned tools, these can be avoided as you can see on many good swords. But I will add that some sword construction methods also might provoke the occurrence of these ripples. I would not consider them negative in technical hindsight at all. Looking at this feature with a microscope/high magnification will clear that up easily.

A KUCHI GANE.

Johnny, these photos are probably historically interesting and rare! Where did you get them from?

Dutch is not a language, it is a throat disease!

Can I send you a "P" for your headline?

Of course it is/was a genuine Japanese blade, but unfortunately, the "cleaned" NAKAGO makes it almost worthless.

And he posted in the wrong section plus the photos are really bad..... Let's give him a second chance next time!

Colin, thank you for your kind words! Your grandfather was in Japan as one of the earliest Europeans and just at an important threshold of Japanese history! He would have seen medieval Japan trying to become a modern nation in a very short period of time! How fascinating that must have been, and how difficult with no internet to ask question, no English speaking Japanese, and no Westerners knowing manners nor language! That would be a topic for a nice film!

That sounds very strange to me and like a translation mistake. I would imagine that making a copy or TSUNAGI was meant.