WIP - Sunahama Kotanto, kaiken meets aikuchi...finished!

[islandblacksmith]

The two parts are tightly bound with a cord or leather strap and wedges further increase the pressure. Using a strap rather than clamps provides an even, non-marring pressure even when the block is not yet perfectly square and true.

This small tsuka will have an unusual ki-fuchi, a wooden accent in place of a fuchi. Pacific Yew is a relatively hard and dense wood with a beautiful rich orange colour and natural gloss. In this case, the accent will be attached to the tsuka and have the grain running vertically to add strength and stability, making it functionally more like a true fuchi rather than a floating tsuba.

Core parts ready for assembly, note that the glue layer is very thin.

Tightly bound with an even winding and pressure, then tension is increased with wooden wedges in certain areas.

After drying 24 hours, the front of the block is leveled and trued using a granite slab.

Pacific Yew sawn to size and cleaned up on the granite slab. Double edged saw has both rip (top of photo) and crosscut teeth (bottom of photo).

A kiri is used to open several holes to rough out the nakago-ana. There are several different styles of kiri bit, this one is a three sided type forged from an expired file. Kiri give great control and can be used much more precisely than a standard modern drill bit.

Small coarse files are used to complete the nakago-ana in the ki-fuchi and the piece is cut to size.

The piece is aligned and bound with the tang in place and then once stable, the tang is removed for drying.

Squaring up the block to the ki-fuchi. A saw file removes a lot of material quickly without deep scarring like a rasp.

Yellow Cedar shims to reduce the strain on the harder Pacific Yew and provide some shock resistance. Carved very carefully!

Shims on all four sides, escapement filed to fit the tang.

Drilling the mekugi-ana using a hand powered post drill. The location on the tang is chosen based on an estimate of best placement on the finished handle, and then the actual hole in the handle is placed based on the location of the hole in the tang. The opening in the tang will be enlarged and adjusted using a round file in the final fitting.


next up, shaping the outside of the tsuka...

 

[evanPGH]

That yew is a terrific color. It will compliment the habaki, seppa and mekugi wonderfully.

 

[islandblacksmith]

Chisels, rasps, and coarse files are used to turn the block of wood into a graceful handle shape and smooth the contours. This would be the final stage for a wooden handle or shirasaya, but this piece will be finished by wrapping over the core with samegawa. Starting from the profile of the seppa, the shape of the handle is carved at the fuchi and then carried back by stages, working from a squared taper to a rounded one. Extra wood is removed to make room for the wrapping to come.

Using a kiri to begin the mekugi-ana, it will be enlarged with a small round file. This can be done later in the shaping process, but old habits die hard and I am not used to how nicely a kiri does the job yet.

Carving the profile down nearer to the finished outline.

Carving the ki-fuchi nearer to the finished shape, based on a tracing of the seppa.

Matching the front of the tsuka to the ki-fuchi.

Tapering the sides back towards the kashira (pommel).

Tapering the corners back towards the kashira.

This would have been the look if the mount was to be a simple wooden kaiken, but we are going to make a small aikuchi mount of this piece.

Setting the depth for the wrapping with a coarse file and carving the core down to meet it.

The tsuka growing out of its block of origin, not much more can be done while it is still attached.

Separating the tsuka from the remains of the block.

Tsuka-shitaji were originally designed to make room for the end knots to sit lower on wrapped handles, however they are often included on the omote side of unwrapped handles as well. My theory is that they serve as a reference point for registering the position of the handle and direction of the blade by feel.

The Pacific Yew for the ki-kashira is cut roughly to shape and glued on to the tsuka core.

The outline has been established, next the contours of the end are carved and smoothed.

A subtle tribute to the yama-no-michi, it will become fairly subtle in the finished design.

Smoothed out showing the grain. The ki-kashira is bookmatched with the ki-fuchi so the swirls in the grain mimic each other.

The finished wood tsuka core. Steps remaining are to coat the Pacific Yew with 100% pure Tung oil and add the wrapping to the handle.

A coat of 100% pure Tung oil brings out the natural glow and colour of the Pacific Yew. Like Walnut and Linseed, Tung oil penetrates the wood cells and then cures, sealing itself in and helping keep moisture out.


more about the process of shaping the tsuka: http://islandblacksmith.ca/process/c...-tsuka-handle/
next stage is wrapping time...

 

[Joss]

Cool work.

 

[evanPGH]

Fantastic curve to the tsuka! Coming along nicely. :thumbup:

The color on the kashira is stunning. Some nice dark orange activity in there.

 

[islandblacksmith]

thanks, @evan...here's a couple early release sneak previews of the proportions...and a couple comparisons for size, this is most definitely a kotanto!

A shot of all the currently existing parts together to give an idea of the proportion and lines, the nakago and mekugi-ana have not had final adjustments yet but its close to home.

Check the yoroidoshi komaru spine on that little beast!

A straight on spine shot showing how the tsuka-shitaji affects the distribution of the handle material.

This is an antique wakizashi shirasaya tsuka (measuring a generous hand and a half) which is closer to the finished size of the whole kotanto and saya than to the tsuka itself!

This is a full sized tanto kata (based on a blade by Shintogo Kunimitsu) next to the kotanto blade.


more about the Aizu Shintogo kata: http://islandblacksmith.ca/2014/04/aizu-shintogo-kunimitsu-tanto-kata/
more about the process of making the tsuka: http://islandblacksmith.ca/process/carving-tsuka-handle/

 

[islandblacksmith]

Ordinarily black samegawa would be created by coating over the rawhide with urushi (natural laquer). In this case a tanned and dyed samegawa will be used for its beautiful appearance, texture, and glassy shine. A paper pattern is made to determine as near as possible the shape of the samegawa needed and then a piece is cut slightly oversize and trimmed down bit by bit. Because the leather is black and the wood very light, strips of dyed paper are glued in place under each of the areas where the samegawa will end. Once this is fully dry, the skin is carefully glued in place and bound with leather cord until dry.

Making and adjusting the paper pattern. Paper does not conform well to compound curves unless wet formed, so this is an approximation.

Shaving down thick areas of the skin from the back. Cutting the skin is a challenge as each node is like a bead of glass.

Dyed paper glued with sokui where the seams and edges of the samegawa will fall. Very reminiscent of sashimono nobori (samurai banners) somehow.

After the skin is glued and fine adjustments are made to placing the seams and edges, it is wrapped tightly with a leather cord to dry.

Omote side with the finished black samegawa wrap.

Ura side, the samegawa meets along the centre, running through the mekugi-ana.



in context: http://islandblacksmith.ca/process/carving-tsuka-handle/#tsukamaki
next up, final fitting and making the mekugi...

 

[evanPGH]

Love it!

 

[islandblacksmith]

In addition to being inserted from the omote side, it is important to note that mekugi also have a correct orientation in the mekugi-ana. The part of the mekugi with the most dots is the outside of the bamboo plant and the strongest. It should be rotated towards the back of the handle, where the nakago places the most strain on the peg.

Because this is a tanto, and a small one at that, the peg need not be bamboo as with a sword. Horn, hardwood, and sometimes metal mekugi are found on antique tanto koshirae. In this case the deep red wood is drawing to mind the colour of an urushi laquer finish. The wood is shaved to a rough taper with a chisel and then smoothed with coarse and fine files as it is slowly adjusted to a final fit before being cut to length. Antler tip leaves a glossy burnished surface and the ends are sealed with 100% pure tung oil.

Creating the taper with chisel and coarse files.

Rounded and smoothed, then burnished with antler.

Finished and ready to drive home for the final mounting.


next it's time for saya...

 

[secretsquirrel]

Thoroughly enjoying this wip, thanks for taking the time to do it, very educational.

 

[islandblacksmith]

The saya should fit snugly on the habaki, with most pressure to the top and bottom, and should hold the blade securely without rattling or jamming. The lines and proportions must be appropriate to the blade and handle and take into account the appearance of the whole unit. As with the tsuka, the mune should be centered in the block of wood but the small flat surface for the edge should be fully seated in the omote half of the wood, slightly to one side. The purpose of this is to align the wood with the tsuka and keep the edge from splitting the glue joint if it ever makes contact with the saya.

Beginning to carve out the omote side.

Glued and wrapped, wedges increase pressure where necessary.

When dry, the final size and shape is determined and sketched out.


more about the saya process: http://islandblacksmith.ca/process/carving-saya-scabbard/
carving the saya is next...

 

[islandblacksmith]

After rejoining the halves, the block is first squared up and then taken down to the rough dimensions. The work is carried out using chisels, planes, and occasionally coarse files. The shape of the koi-guchi (saya opening) is marked and carved and then the rest of the block is chiseled down to meet it.

The block is planed down square to slightly above the final size.

The koi-guchi is carved down with a chisel or kiridashi. Astute students of nihonto will notice the ha is resting in the ura rather than omote, this is due to a wood issue with this specific piece.

A chisel and plane are used to create the final shape and true all surfaces.


more about the saya process: http://islandblacksmith.ca/process/carving-saya-scabbard/
finishing the saya is next...

 

[islandblacksmith]

A plane is used to smooth and true up the surface and final sanding is done with tokusa (horsetail plant) glued to wooden blocks with sokui (rice paste glue). Finally the saya is burnished with antler and coated with 100% pure tung oil to bring out the colour and provide some protection for the wood.

Tokusa sanding blocks can be made in all sizes and shapes. Tokusa gives a finish that is a cross between fine sanding and burnishing, but does not leave grit as sandpaper can.

Omote with white ghost tracks in patterns like insect tunnels. Tung oil gives the wood a rich glow and fills the wood cells before curing into a solid barrier, preventing moisture and other substances from filling the cells.

Ura with pure red streaks and a nice flamed tip. Wabisabi is the order of the day.


more about the saya process: http://islandblacksmith.ca/process/carving-saya-scabbard/
getting close! final polish is next...

 

[SBranson]

More interesting stuff. I recently visited with a local guy who has been polishing swords for about 25 years, Martin White. He made some shirasaya and burnished the wood with a piece of maple. I've heard of using tokusa but hadn't known about the burnishing before. Being a woodworker it's a really odd finish I hadn't really seen before. It almost made the wood feel like it had been coated in some epoxy like substance and the sound the wood makes when you tap it with your nail was a mystery to me.

Definitely something I'm going to explore.

 

[remy b]

I'm loving every bit of that WIP.

THX!

 

[islandblacksmith]

@Stuart yes, it makes for an interesting finish, different woods respond differently but it seems to work well on both harder and softer woods...you can most clearly see the difference in the second mekugi photo: #post13405475

how local is Martin White? does he have a website?


@rémy, @secretsquirrel, @joss ...thanks, almost there!

 

[evanPGH]

Omote looks like a shoreline going from left to right. Very fitting considering you're at one ocean and I'm at another!

 

[Lorien]

I'm super impressed!

 

[islandblacksmith]

just a quick preview shot of the whole koshirae...antique calligraphy box is the urushi colour that the mekugi is honouring...blade is in queue on the togi dai right now...

At this point the koshirae is complete. Once the blade has been given the final polish it will be fully assembled.

 

[orangehero]

Beautiful. Do you have a shot of the handle from the obverse side?