mas4t0

That's amazing Matt! Thanks for sharing.

Wonderful write up Ford. Thank you for sharing your insight. I feel like an organic living thing becomes perfect (or at least works towards it) by living, by growing, adapting and changing. It's developing and becoming more complete, mature and complex as time passes. In that sense, it feels as though a lot of Japanese art really is imbued with a life of its own.

In England we use dodgy to mean something or someone unreliable or suspicious So in Aus would dodgy mean naff too? Also, here, 'a bit' is often a polite was of saying 'very'. ????

I think Ken that you'd maybe say 'tacky'. I've heard American friends refer to naff things as being tacky, wack or lame.

My understanding is that the 'modern science' is simply some mechanisation of the process in order to reduce the amount of manual labour involved. I wouldn't expect the steel to be any different metallurgically, and the aim here seems to be only to increase supply and make the material more readily available. I don't quite understand what you are hoping to achieve; if you can elaborate, it might enable some more precise responses. Just for completeness, if you're looking for a Japanese (style) sword made taking advantage of modern heat treat and metallurgy then you'd be best served looking at non-nihonto made by smiths outside of Japan.

It's purely physical. Find the point of balance of the sword (including the tsuka). This is the Centre of Mass (CoM), the CoM is the point at which a force may be applied to cause a linear acceleration without an angular acceleration. The distance from the tsuba to the CoM along with the mass (and distribution thereof) of the sword and the mass of the tsuba itself will determine how the CoM will move in response to the tsuba. A mass of 100g added at 50mm from the current CoM will have the same effect as 50g at 100mm, as the moment is the same. Due to the tsuba being relatively close to the CoM, it would have nowhere near as much of an effect as adding mass to the kashira (which is why western swords use pommels). If you want to understand this fully, search for "Centre of Mass." I think though that the effect may be missed somewhat if we only consider the CoM. As Malcolm expressed, the results are best felt and assessed during suburi where you're getting feedback on the dynamics of the sword. Dynamics are also purely physical, so can be easily calculated, but it's best done with software rather than pen and paper as it gets somewhat more involved to calculate. The effect of the tsuba will be small but noticeable. If you search from "Weapons Dynamics Computer" in Google you'll find a well put together tool. You can adjust different parts and see how it affects the overall dynamics of the sword.

I still don't know what 'iron quality' means in this context, but I'm not convinced that it's a case of "I know it when I see it." I'd understood Ford's comments as saying 'iron quality' can't be seen; that we can't assess it by judging the surface appearance and patina.

On the other hand, Uesugi Kenshin would likely have disagreed with this point of view. I wasn't meaning to imply that Tsuba didn't serve an important function, but that they don't require the finest Iron in order to serve their function admirably.

Greater Ductility goes hand-in-hand with greater Fracture Toughness. I would presume that Copper offers sufficient Hardness for the needs of a Tsuba, and pure Iron is both significantly Harder than Copper and Tougher than impure Iron. If we need additional Strength then we want higher Carbon content, but would still be best served by the purest steel. In this example, I'm looking at this from the perspective of Mechanical Properties, and I'm probably optimising for the wrong things. That's the point though, the "best" will depend on what our criteria are. I would presume that in the end it all comes down to aesthetics. An Iron tsuba is not an engineered product and does not require the material to be well optimised in order to adequately perform its function.

The 'best Iron' from a purely metallurgical/ chemical stand-point would be the purest, most homogeneous Iron with the least impurities. The closest to Electrolytic Iron. This would not be the 'best Iron for tsuba' (if we have any aesthetic sensibilities) as the plate would likely be plain, flat and featureless. There is of course no way to assess the mechanical properties of the Iron through handling. Even with suitable equipment we could most likely only measure surface roughness and specific weight without using destructive testing techniques.

I'm not sure if he's NUTS, but he certainly has a few SCREWS loose.

Who decided that EMF = spirits? You'd just be testing if there's any active telecommunications equipment nearby.

All a polish can really do is clean up a blade, you can only uncover what's there. Material obviously can't be added back in. With many other forms of art a restorer has a lot more options. A canvas which is split can be rejoined, cracked paint can be filled in and loose paint can be bonded down; you can add to the painting to repair areas of loss and damage. In that field, I have seen some restorations that I would consider to be bordering on 'miraculous'.

I didn't miss that we're in the Tosogu sub-forum... I get the impression that rather than a debate over the meaning of 'best' (which this has become) the intention of the thread was to ask what people's preferences were (with regards to different schools) and why.

For clarity, are you really asking for people's favourite iron (as opposed to the best) along with an explanation of why they have those preferences?

Thank you for elaborating, it's an interesting idea. Howard uses salt baths so I'm sure he's using a variation of the Austempering process.

Just to add some more info, you'd usually produce Bainite by Austempering, which is the process described. The key part is the quench. It's usually done in a molten salt bath and then held for a while to allow Bainite transformation.

I'd be curious when the analysis was done, just because Bainite was originally described as being similar in appearance to tempered martensite. I seem to recall some analysis done on Nihonto a little over a decade ago at my alma mater and I don't recall any mention of Bainite.

Focus stacking in a nutshell is when you take multiple photos on a tripod with the same settings, but focusing on different parts of the subject (different distances) and then digitally combine them to create an image where everything is in pin sharp focus. It creates great results, but you can get great results with manual settings. I find that square-on there's usually not a need for focus stacking and it becomes much more relevant when dealing with an isometric projection or when there is a distinct foreground and background which you're looking to keep in focus. The effect is nicely illustrated if you hold a finger up on front of you, you'll find that if you're very close to a wall you can focus on both, but you can't move far from the wall before you can focus on only one or the other.

To my eye these are somewhat reminiscent of extremely high class marquetry, the work of Jan van Mekeren comes immediately to mind.

Any chance you could post a picture of the one you have?

Thank you John. Are there any units for the table? I took a look through the site, but down see any reference to the units. It can't be HRC though as steel tops out at ~65HRC and we have numbers here >80.

That's a great answer Joe. Thank you for elaborating. I too have a fondness for modern blades, including western smiths working in the Japanese style. I have a hira-zukuri katana in folded modern steel from Walter Sorrells which is one of my favourites.

I prefer to keep things stored out of sight. I don't like to leave anything delicate out on display and I find that if something is sitting out as a part of the decor, I get bored of it within a year or so and make plans to move it on.

Wouldn't an utsushi be based on a particular work rather than more broadly inspired by the collective works of an artist or an era?