Yozakura Tanto & Koshirae

[DaveJ]

The nightime viewing of cherry blossoms by moonlight is cherished for the unique perspective and focus it brings to the experience. The dark tones of the sky and the gentle light of the moon provide subtle variations in colour, texture, and detail that cannot be fully appreciated by day.

This kotanto is made from reclaimed shear steel from a horse-drawn carriage leaf spring and is housed in a koshirae that is somewhat reserved in its combination of materials and colours, evoking the feeling of a familiar and treasured object.

The raw material for this blade spent more than the last century as a leaf spring for a horse-drawn carriage. This "secret source" pile is located on a former homestead of a blacksmith so it has a high proportion of carbon steel, saved for its value and usefulness in making tools and implements.


A comparison of the steel before and after forging, the area between the chalk lines was forged into the blade. The material to the left of the chalked area is rusted too thin to be forged, and the material to the right will become a larger tanto. There is a divot on the spring which can still be identified as a dark line in the tang just behind where the habaki sits.


The clay mixture dried on the blade in preparation for traditional yaki-ire style hardening. The thicker white layer delays cooling and the thinner charcoal-rich layer speeds up cooling, causing the blade to form two types of steel crystal, harder for the edge and tougher for the rest of the blade.


Immediately after hardening, the blade has been heated to critical temperature and then plunged into a hot water bath to cool. Once the clay is removed it will be tempered slightly to remove some of the stress along the edge.

 

 

Edited January 5, 2018 by DaveJ

[DaveJ]

Hounoki (Japanese Magnolia) forms the core of the handle, local Nootka Cypress for the scabbard, and carved horn for the mekugi (peg). The handle is lacquered with multiple layers, first a bark-textured crimson and then overlaid with thin layers of natural and black in the kurodamenuri (tamenuri) style which reveals the interior only in strong sunlight. The shape of the kashira (pommel) is in the style of keito kashira (圭頭).

A stone textured surface created with natural urushi lacquer and crushed iron oxide reclaimed from discarded kairo (hand warmer packs) gives a crimson-rust appearance to the scabbard. The habaki, fuchi, and koiguchi were forged from copper scrap and simmered in a niage bath to give them a rich rose-plum copper oxide patina.

 

Using the charcoal forge to silver solder the two parts of the forged copper habaki together. Forming an "oven" from charcoal and keeping the air blast as low as possible helps prevent oxygen from contaminating the joint and provides an even heat.

Using rasps, files, and finally a water stone to shape and polish the finished habaki.


Annealing scrap copper electrical bus bar to begin forging the fuchi. Heating aged copper creates interesting colours as the oxides and salts burn off the surface.


Forging and filing to shape the two parts for the fuchi. Scrap electrical-grade copper is relatively pure and forges well.


Cooling the fuchi after silver soldering the two parts together in the charcoal forge. The oxidized steel wire provides tension as the parts are heated but does not stick to the solder in the event of an excess.


Hounoki (Japanese Magnolia) is carved to fit the tang snugly and then glued together with rice paste to form the core of the handle.


After shaping with planes, chisels, and a knife, it is given several base coats of urushi lacquer.


A bark textured layer coloured with crimson lake pigment is polished slightly.


Contrasting layers of natural and black urushi are layered over it and polished to begin to level the surface.


Finally it is coated with very thin layers of black urushi to partially obscure the colour underneath. This layered finish style is called kurodamenuri (tamenuri), the interior is revealed only in strong sunlight.


As with the handle, the scabbard is split and carved to fit the blade, then glued back together with rice paste. When dry it is carved to shape using knives, chisels, and hand planes.


The finished wood scabbard is coated with several layers of urushi lacquer and then sprinkled with iron oxide to give it a textured look. The iron oxide comes from reacted hand warmer packs, called kairo.


After several more coats of urushi the iron oxide has become a stone texture surface known as ishimeji.


Cord fittings for the koiguchi are forged, filed, and chiseled from various sizes of scrap copper wire.


The copper fittings are cleaned and then simmered in a niage bath to give them a rich rose-plum copper oxide layer.


The fittings are coated with a layer of natural ibota wax to seal the patina before being mounted to the saya and tsuka.

 

 

Edited January 5, 2018 by DaveJ

[DaveJ]

A single stylized sakura petal graces the copper fuchi, a reminder that even a single petal falling to the ground does not go unnoticed and is not without significance.

One of the elements of traditional Japanese aesthetics includes the appreciation for the natural process of wear, decay, and patina. Historically, this was expressed in the use of materials that bear the marks of longevity and even the creation of new objects that appeared to be aged, rugged, or bearing certain types of imperfection.

Materials: Century-and-a-half-old horse carriage spring shear steel, copper electrical bus bar, copper lightning rod cable, Hounoki, Nootka Cypress, iron oxide from reacted kairo, natural urushi lacquer, crimson lake, leather, reclaimed buffalo horn

 

Specifications

長さ/刃長 Nagasa: 4 sun 4 bu 6 rin (132mm)
元幅 Motohaba: 7 bu 8 rin (23.5mm)
重ね/元重 Motokasane: 2 bu 4 rin (7mm)
反り Sori: uchizori
中心/茎 Nakago: 3 sun 1 bu (93.5mm)
柄長 Tsuka: 3 sun 1 bu 5 rin (95mm)
拵全長 Koshirae: 9 sun 2 bu 4 rin (279mm)

形 Katachi: hira-zukuri, iori-mune
刃文 Hamon: suguha
帽子/鋩子 Boshi: ko-maru/tsukiage
中心/茎 Nakago: futsu, kuri-jiri, one mekugi-ana, signed near the tip
銘 Mei: hot stamped katabami-ken kamon
拵 Koshirae: keito kashira aikuchi, issaku

 

More info: islandblacksmith.ca/2015/05/yozakura-tanto/

yoroshiku!

 

 

Edited January 6, 2018 by DaveJ
new photos...

[John Page]

Wow! It's always a pleasure to see your work and the mindset behind it. I love the use of reclaimed materials and the traditional methods of forming them. The kairo and lacquer both give an incredible finish! A long while ago I thought about using those iron oxides for something but came up with nothing worth pursuing. Your work is an inspiration!

 

John

[DaveJ]

Thanks, @John!

 

i've often thought if you had enough of them saved you could use the oxide as a raw material or at least a supplement to a smelt...

[Wesley Alberson]

Absolutely stunning work! I had no idea copper could be plum colored! Thank you for posting the processes of your work. It has helped me make a couple knives of my own. I had started forging seven months ago and your process pictures are my main go-to every time I run into a problem, as well as when I need some inspiration! I can't wait to see that spear (I think it was) from instagram finished!

[DaveJ]

Thanks, @Wesley! it is a lovely colour indeed...the finished shots look a little more terracotta because i used a polarized filter to help with reflections, the final shot in the process post looks closer to the real thing on my screen...

 

yes, the sankaku yari is a lovely form and a challenge to forge!

Edited January 5, 2018 by DaveJ

[Wesley Alberson]

Thanks, @Wesley! it is a lovely colour indeed...the finished shots look a little more terracotta because i used a polarized filter to help with reflections, the final shot in the process post looks closer to the real thing on my screen...

 

yes, the sankaku yari is a lovely form and a challenge to forge! ...that one will not likely make it out into the world, as i forged and worked with it i felt like the carbon level was too low...i finished shaping it as a personal development project but i do not think it will take a good hamon...

Well it might be a stretch/impossible, but what about exposing the spear to some carbon-rich environment to at least make the edges able to harden? I've never tried putting carbon into steel, so I don't exactly know how difficult it is to do something like that.

[Pieter-Paul Derks]

fantastic work as always, i love how you aslo take fantastic pictures to show your work and the process.

 

i am also very inspired by that plum colour, it makes me want to experiment with copper and patination.

[Collin Miller]

I always like you you show the process in detail as well as the finished piece. Everything looks great, I think i need to come up with a stash of old metal.

[Alan Longmire]

Oddly enough, I find it very peaceful and meditative to see your progress shots. As for what you can do with reclaimed materials, well, am in continual awe! Inspirational!

[John Page]

I've often thought if you had enough of them saved you could use the oxide as a raw material or at least a supplement to a smelt...

 

Not to derail everything here, but I had similar thoughts! Maybe throw a bunch of it in a crucible? I'll have to solicit my family up north this winter to save all the ones they use

[J.S.Voutilainen]

It is difficult to comment work like this. I would struggle even in my own language, let alone in english. This is so incredibly beautiful on every level. Shattering and perception altering.

 

As I write this the sun is rising. A perfect start to a day, thank you!

[Jan Ysselstein]

Dave,

 

Amazing work , again. The demo or tutorial is very appreciated, so well done.

 

I am not sure I understand the heat treating here,

 

"Immediately after hardening, the blade has been heated to critical temperature and then plunged into a hot water bath to cool. Once the clay is removed it will be tempered slightly to remove some of the stress along the edge."

 

Are you quenching twice?

 

Thank you,

Jan

[Wes Detrick]

Always a treat to see your work Dave. As everyone has already said, the process pictures(and just well you do them) is the icing on the cake. It's a gorgeous knife you have made. Thanks for sharing!

[Miles Hebbard]

Fantastic post! Thanks for sharing!

[Jesus Hernandez]

Beautiful photography. Thanks for documenting the process.

[Kevin Colwell]

for whatever reason, I can't open the process pics. still, this is a great creation. I love the attention and care that you give to each piece. It is, for probably most of us, as Alan accurately stated. The process is meditative, and seeing pics of someone else's work, at best, can evoke the same feelings.

 

Jim Kelso's work does the same.

 

great job. thanks for sharing so much with us.

kc

[Jim Kelso]

Dave, another wonderful sequence. The whole package is so integrated and well designed.

Well done!

[Jess Yeigh]

Dave

Inspirational work, your commitment to tradition and form is moving. I promise I will get that wrought iron to you

Jess

[SBranson]

Oddly enough, I find it very peaceful and meditative to see your progress shots.

 

 

This is the same feeling I get from this piece. Your story of the the sakura viewing is so well conveyed in this piece and the photography. You have a way of presenting your work that is integral to the piece itself. You are not a reporter but storyteller and I applaud your artistry in it's full expression.

[DaveJ]

@Wesley i want it to take a traditional hamon, so will see if it does as is...if not i may have to mount it on a pole and keep it at the back door for the cougars...

 

@pieter-pauld this is based on niiro recipe #4 from the hallam paper, it seems to work fairly well for copper if the "real thing" is unavailable

 

@Collin there is a lot of old steel out there, go for it...working with unknown (but old) steel is a good way to develop a sensitivity to carbon content and other factors in the way traditional smiths would have had to understand and use their own-made steel...

 

@Alan thank you, it is a big part of the process, and so is the process! sharpening and using hand tools provides lots of time to reflect ^__^

 

@John you would need to run them through a tatara-like charcoal furnace so the oxide would be reduced back into iron/steel...get collecting!

 

@J.S. kiitos paljon (?) ^__~

 

@Jan i could have written that more clearly...the photo was shot immediately after hardening (quenching) but before tempering...

 

@Wes and thank you for keeping those photos coming!

 

@Miles, @Jesus, @Jim, @Jess, @Stuart very much appreciated!

 

@Kevin, here is the link to the post, try copy and paste: islandblacksmith.ca/2015/05/yozakura-tanto/

[Tiaan]

I'm always inspired by your approach and the appreciation of the tradition you so clearly illustrate. Brilliant work and amazing photography. Amazing how so many people feel the peace that comes across so strong in your work. As blade smiths we transfer a little bit of ourselves into our work every time hammer meets steel and I believe the emotions with which the work was created remains.

[jdsmith02115]

Superb effort and results!!

[DaveJ]

thanks, @Tiaan, yes...residual emotion is an interesting concept!

 

very much appreciated, @jd!