|
Post by tsmspace on Mar 17, 2020 16:10:45 GMT
I bought a new sword, I'm pretty happy so far, having sat with it in my bedroom. I have no doubt that the sword will stand the test of time if I am careful while I chop plastic bottles. However, I am interested to discuss what I might know. The sword is a differential hardened katana. It's 200$ from True Swords , and is a Sokojikara t-10 katana. Here is the Hamon I've seen people break the sword to inspect the heat-treatment, but if that's not my plan, what can I see from the outside?? The blade is immaculate. It looks good. However, it's not exactly expensive, at 200$, and because there are swords with the T-10 steel that are coming in at much higher prices (and the same story goes for other metals, there are 1060 swords at thousands of dollars), I am sure there are reasons for the elevated price besides the wood in the handle.
|
|
|
Post by treeslicer on Mar 17, 2020 17:49:28 GMT
I bought a new sword, I'm pretty happy so far, having sat with it in my bedroom. I have no doubt that the sword will stand the test of time if I am careful while I chop plastic bottles. However, I am interested to discuss what I might know. The sword is a differential hardened katana. It's 200$ from True Swords , and is a Sokojikara t-10 katana. Here is the Hamon I've seen people break the sword to inspect the heat-treatment, but if that's not my plan, what can I see from the outside?? The blade is immaculate. It looks good. However, it's not exactly expensive, at 200$, and because there are swords with the T-10 steel that are coming in at much higher prices (and the same story goes for other metals, there are 1060 swords at thousands of dollars), I am sure there are reasons for the elevated price besides the wood in the handle. I haven't handled one yet, but the reviews are good. My only objection to the Sokojikara (the name means "power in reserve" in Japanese) is the very visible branding on it. As far as evaluating the heat treat, the hamon may examined with a magnifier to observe and appreciate the crystal structure, and compared with known good examples. The ha ("edge") may be tested with a file to see if it skips off, and the back ("mune") likewise to see if the file will cut there (as it should). The ha should be slow to sharpen with water or oil stones (except diamond), and the ha should hold a nail-hanging, hair-shaving razor edge as well as allow clean cutting of pool noodles, mats, and green bamboo (if your skill allows it) without edge damages such as chipping or rolling.
If these things hold up to use and get good reviews for a while, and the price stays low, they'll probably become a standard go-to bargain.
|
|
|
Post by RufusScorpius on Mar 17, 2020 18:08:16 GMT
There are two kinds of tests for heat treating: destructive and non-destructive. Since the destructive tests have been ruled out, the only thing left is the non-destructive. Non-destructive is essentially surface hardness testing. I assume you don't have access to a laboratory with the correct equipment, so as such, what Treeslicer said is the only real way to do it at home.
However, not all files are created equal. It is important to get a good brand name file that itself is correctly hardened. A low quality file will not give the results you want. Other than that, if the file bites the metal then you know the metal is less hard than the file. If the file doesn't bite, then the metal is harder than the file. It does not give you a measurable number, but it will at least tell you a rough approximation of the treatment of the metal.
However (again), harder is not always better. Softer steel won't keep an edge for as long as hardened steel will, but it is super easy to fix because it will bend before it breaks. It's a trade off- as hardness goes up/ flexibility goes down. Finding the happy medium is the question.
Personally I prefer spring steel because it's hard enough for my purposes, yet nearly impossible to break. Softer steels are easier to sharpen and a good choice for backyard bottle cutting or practicing sharpening techniques.
After all this wordiness, just do what Treeslicer said.
|
|
|
Post by AndiTheBarvarian on Mar 17, 2020 18:56:59 GMT
There exist file sets with small files of different hardness with steps of 5 HRC hardness difference, from 40 - 65 HRC. But you'll scratch the blade surface this way, so it's not completely "non destructive".
|
|
|
Post by alexkjren on Mar 17, 2020 18:59:35 GMT
There are two kinds of tests for heat treating: destructive and non-destructive. Since the destructive tests have been ruled out, the only thing left is the non-destructive. Non-destructive is essentially surface hardness testing. I assume you don't have access to a laboratory with the correct equipment, so as such, what Treeslicer said is the only real way to do it at home. However, not all files are created equal. It is important to get a good brand name file that itself is correctly hardened. A low quality file will not give the results you want. Other than that, if the file bites the metal then you know the metal is less hard than the file. If the file doesn't bite, then the metal is harder than the file. It does not give you a measurable number, but it will at least tell you a rough approximation of the treatment of the metal. However (again), harder is not always better. Softer steel won't keep an edge for as long as hardened steel will, but it is super easy to fix because it will bend before it breaks. It's a trade off- as hardness goes up/ flexibility goes down. Finding the happy medium is the question. Personally I prefer spring steel because it's hard enough for my purposes, yet nearly impossible to break. Softer steels are easier to sharpen and a good choice for backyard bottle cutting or practicing sharpening techniques. After all this wordiness, just do what Treeslicer said. I don't know where to get them, but I've seen others with more experience than me talk about file kits they have expressly designed to test metal hardness so the files themselves are marked for their hardness. The ones I've heard people talk about usually come in 4-6 packs so you're not going to get high precision but you should be able to a measurement that falls in a range.
I remember Lancelot Chen did a test like this on another forum years ago. I think his was a 5 file set that had files hardened to 40HRC, 45HRC, 50HCR, 55HRC, and 60HRC
Good luck!
|
|
|
Post by tsmspace on Mar 18, 2020 6:56:26 GMT
I haven't handled one yet, but the reviews are good. My only objection to the Sokojikara (the name means "power in reserve" in Japanese) is the very visible branding on it. As far as evaluating the heat treat, the hamon may examined with a magnifier to observe and appreciate the crystal structure, and compared with known good examples. The ha ("edge") may be tested with a file to see if it skips off, and the back ("mune") likewise to see if the file will cut there (as it should). The ha should be slow to sharpen with water or oil stones (except diamond), and the ha should hold a nail-hanging, hair-shaving razor edge as well as allow clean cutting of pool noodles, mats, and green bamboo (if your skill allows it) without edge damages such as chipping or rolling.
If these things hold up to use and get good reviews for a while, and the price stays low, they'll probably become a standard go-to bargain.
My hope is that because it is a bit harder on the rockwell (hopefully, but comparing two cheap swords it should win just for the choice of metal), and holds a nicer edge, and it's ok for me if it would break when I really work it, because I won't probably do that, I wanted it to sharpen. I don't mind the logos, or the cheap look of the furniture, because when I hold it, it feels pretty stable, and it looks like a very nice blade. The bevel is VERY aggressive compared to my shinwa katana, the spines are the same thickness, but the sokojikara is thinner across the body of the blade, and approaches the edge with a very thin blade. (so, it looks like it will sharpen amazingly, but it looks like don't go destructive testing, it will break) They apparently make a spring steel version, which I might also purchase because how interesting, but I can only imagine the t-10 version should hold a much finer edge, and my whole thing right now is I want to practice sharpening. (my stone should be here at the moment, but I think someone upstairs has my mail, so I should have a nice King KDS 1000/6000, easily the finest stone I've ever considered owning)
|
|