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- Dec 24, 2012
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- 2,659
Thanks Rolf but I really don't deserve any credit here.
This is all Dave, I just knew what I wanted and he took it from there. =)
-
The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details: https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is$300$250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
WIP - Sunahama Kotanto, kaiken meets aikuchi...finished!
- Thread starter islandblacksmith
- Start date
Thanks Rolf but I really don't deserve any credit here.
This is all Dave, I just knew what I wanted and he took it from there. =)
- Joined
- Jan 2, 2014
- Messages
- 297
the clay mixture is approximately thirds of regular clay, charcoal powder, and ground stone/sand...the clay provides the stickiness, the charcoal helps prevent flaking off in the fire, and the stone/sand prevents shrinking when drying...
first a thin layer of slip that is higher in charcoal content (some of it in the form of lampblack), the charcoal burns out in the fire and the resulting porous surface has been found to cool steel faster than if it was bare...the slip also helps prevent oxidation and decarb while in the fire...it really only needs to be at the edge as the rest will be covered by the thicker layer of clay
for this batch i ground up some iron oxide (rusted filings) to add to the outer layer, ground between two stones to make sure there are no large chunks
i have a batch of the clay mixture (~1:1:1) already blended, dry clay does not mix evenly until it soaks awhile so i keep it in a jar premixed...the process of making it is similar to the shot above but longer and for each ingredient in small amounts at a time, water is from snow that never touched the ground ^__^
i am going for an austere but slightly modulated suguha or ko-midare pattern and keeping it very narrow as the piece is small and will want to through harden easily...even the runout at the hamachi and the turnback at the tip are mostly created by exposing the flat surface of the front of the nakago and the mune behind the tip...
the clay is fairly dry after sitting overnight, i will still heat it slowly at first to minimize any steam explosions blasting off a piece of clay in the fire...next up, the moment of truth...will a blade be born?
first a thin layer of slip that is higher in charcoal content (some of it in the form of lampblack), the charcoal burns out in the fire and the resulting porous surface has been found to cool steel faster than if it was bare...the slip also helps prevent oxidation and decarb while in the fire...it really only needs to be at the edge as the rest will be covered by the thicker layer of clay
for this batch i ground up some iron oxide (rusted filings) to add to the outer layer, ground between two stones to make sure there are no large chunks
i have a batch of the clay mixture (~1:1:1) already blended, dry clay does not mix evenly until it soaks awhile so i keep it in a jar premixed...the process of making it is similar to the shot above but longer and for each ingredient in small amounts at a time, water is from snow that never touched the ground ^__^
i am going for an austere but slightly modulated suguha or ko-midare pattern and keeping it very narrow as the piece is small and will want to through harden easily...even the runout at the hamachi and the turnback at the tip are mostly created by exposing the flat surface of the front of the nakago and the mune behind the tip...
the clay is fairly dry after sitting overnight, i will still heat it slowly at first to minimize any steam explosions blasting off a piece of clay in the fire...next up, the moment of truth...will a blade be born?
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- Jan 10, 2010
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- 1,818
Very cool Dave. Always interesting to see how other people handle their clay application.
- Joined
- Jan 2, 2014
- Messages
- 297
because this is a "modern" steel (ie. made sometime in the past 100 years or so) i know it's likely to have traces of molybdenum and manganese and will harden much more deeply than the simpler steel made from tamahagane so i want to preempt the deeper hardenability by under shooting, especially on such a small blade...i think even just the flat face of the edge would be enough near the tip at this scale...
- Joined
- Jan 10, 2010
- Messages
- 1,818
hmmm.. mill saw blade. That is indeed deep hardening steel... whatever it is. Folks use to always say 'L6'.. but I don't think it true all the time. What is your experience with hamons on that material?
Scott Richardson (Cariboo Blades) is up your part of the world and he uses those big saw blades too. I love the pictures on his website showing one hanging with a bunch a knife cut-outs in it.
Scott Richardson (Cariboo Blades) is up your part of the world and he uses those big saw blades too. I love the pictures on his website showing one hanging with a bunch a knife cut-outs in it.
- Joined
- Jan 2, 2014
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- 297
i don't often use millsaw blades in general (mainly because cutting them up is a pain!), but i encountered this one when i did some tempering for a friend...i was quite impressed with it, that's why i tried to trade and deal with him for the rest of it...
this is the unpolished piece i forged from a discarded blank of his as a test before heat treating his finished blade (which was also made from this steel), scroll down to see the two shots of the hamon at different angles:
http://islandblacksmith.ca/product/integral-camp-knife/
this is the unpolished piece i forged from a discarded blank of his as a test before heat treating his finished blade (which was also made from this steel), scroll down to see the two shots of the hamon at different angles:
http://islandblacksmith.ca/product/integral-camp-knife/
- Joined
- Dec 24, 2012
- Messages
- 2,659
That steel produces a very nice result IMO.
I love to think of that saw blade's story...where it was used to do it's job and how it ended up in your forge.
Great stuff!
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- Jan 2, 2014
- Messages
- 297
when i quench (harden) knives, i close the shop doors and turn out the lights in order to give me a consistent level of light each time...the clay coated blade is heated carefully and evenly (in a charcoal forge) up to slightly above critical temperature and then cooled in a bath of hot water...the clay mask of the body of the blade delays cooling by a few fractions of a second, but enough to cause two different types of steel crystals to form, giving the blade a very hard edge with a tough body...
caught this lovely moment of the dance while working on other forging to warm up the quench water...playing with shutter and aperture and fire...i quite like the lens flare
quench tank is warm and set on the anvil for quick access...it is rain water filtered through the moss on the roof and has charcoal dust from the forge floating on the surface
set up above the glowing coals for a few minutes with no air blast just to make sure the clay is fully dry
right after turning the air back on, heating the spine first, keeping it moving constantly...a flake popped off one side, but it was thin and the coat was thicker than normal anyways
i let it cycle once sitting on a block of charcoal to air cool to black, this allowed me to watch the recalescence with the bonus of an extra chance for things to normalize...you can see the darker pre-recalescence "ring" starting to enter the blade near the tip and tang
a bit of a blank in the timeline while i concentrate on the fast paced action...using the magnet again to double check the colour and then evenly heating the whole blade until the edge is as close to the final heat as possible, a microscopic boost to the heel (the tang will suck some heat out during the transfer) and thinner area at the tip last and then into the water edge (and slightly point) first and hold until it cools...this photo is right after i pulled it from the bath, still steaming
this is the post quench clay, this mixture really held well, it is normal for a lot of it to pop off at the time of the quench...as soon as its out of the bath i test the edge with a file to see if it has fully hardened, the file won't cut into this steel at all so we have quench! if it was soft anywhere (tip and heel can be problem areas) i would normalize, reclay, and repeat the process...
cleaning off the clay with a mild steel scraper, the edge steel is very hard, to the point of brittleness at this point so i treat the blade as if it were glass, especially the thin tip with turnback area
looks good, no cracks, a blade is born! the hamon will not likely lay right along this line, though it is a good indicator of things that went on at the right temperature and time
omote, will see when things are all said and done, but perhaps there is a different hamon line on each side, some variation is possible with such a thick cross section blade...i gave this a very light oven tempering to keep the edge quite hard, charcoal tempering such a tiny blade makes me a bit wary of overshooting my target
still may not be the final location but the 120 grit sun tiger waterstone does give a promising preview of things to come (now you see why i rode the edge so close with the clay mask!)...spoiler alert: lots more of this polishing activity is next!
caught this lovely moment of the dance while working on other forging to warm up the quench water...playing with shutter and aperture and fire...i quite like the lens flare
quench tank is warm and set on the anvil for quick access...it is rain water filtered through the moss on the roof and has charcoal dust from the forge floating on the surface
set up above the glowing coals for a few minutes with no air blast just to make sure the clay is fully dry
right after turning the air back on, heating the spine first, keeping it moving constantly...a flake popped off one side, but it was thin and the coat was thicker than normal anyways
i let it cycle once sitting on a block of charcoal to air cool to black, this allowed me to watch the recalescence with the bonus of an extra chance for things to normalize...you can see the darker pre-recalescence "ring" starting to enter the blade near the tip and tang
a bit of a blank in the timeline while i concentrate on the fast paced action...using the magnet again to double check the colour and then evenly heating the whole blade until the edge is as close to the final heat as possible, a microscopic boost to the heel (the tang will suck some heat out during the transfer) and thinner area at the tip last and then into the water edge (and slightly point) first and hold until it cools...this photo is right after i pulled it from the bath, still steaming
this is the post quench clay, this mixture really held well, it is normal for a lot of it to pop off at the time of the quench...as soon as its out of the bath i test the edge with a file to see if it has fully hardened, the file won't cut into this steel at all so we have quench! if it was soft anywhere (tip and heel can be problem areas) i would normalize, reclay, and repeat the process...
cleaning off the clay with a mild steel scraper, the edge steel is very hard, to the point of brittleness at this point so i treat the blade as if it were glass, especially the thin tip with turnback area
looks good, no cracks, a blade is born! the hamon will not likely lay right along this line, though it is a good indicator of things that went on at the right temperature and time
omote, will see when things are all said and done, but perhaps there is a different hamon line on each side, some variation is possible with such a thick cross section blade...i gave this a very light oven tempering to keep the edge quite hard, charcoal tempering such a tiny blade makes me a bit wary of overshooting my target
still may not be the final location but the 120 grit sun tiger waterstone does give a promising preview of things to come (now you see why i rode the edge so close with the clay mask!)...spoiler alert: lots more of this polishing activity is next!
Last edited:
- Joined
- Jan 2, 2014
- Messages
- 297
whoa...this is a custom knife for a client from the Custom & Handmade Knives area of the forum, somehow it has been relocated without a forwarding address (^.^)
...just found this: http://www.bladeforums.com/forums/showthread.php/1154819-No-WIPs-in-the-Custom-forum
thanks, mods, the glitch has been fixed, back to the grindstone...actually waterstone (^_~)
...just found this: http://www.bladeforums.com/forums/showthread.php/1154819-No-WIPs-in-the-Custom-forum
thanks, mods, the glitch has been fixed, back to the grindstone...actually waterstone (^_~)
Last edited:
- Joined
- Jan 2, 2014
- Messages
- 297
the goal of this phase is to remove the steel surrounding the edge and define the geometry of the blade, and then to begin the work of polishing and refining the shape...once it is at its final shape and the heavy scratches are removed, the polishing process is interrupted until the habaki, tsuka, saya, and any other mountings are made...this protects the final polish from any wear and tear while the koshirae are fitted to it...one of the beautiful things about a knife that can disassemble!
Sun Tiger used to make these as well...hand cranked grinding wheel (circa? Anyone know?) until i find a good 50 or 80 grit stone, this is the best human-powered way of knocking off the bulk of the super-hard steel left at the edge after yaki-ire...on this little blade it takes less than an hour to do a decent job with this, more than six with only a 120 grit flat stone!
the finish created by a 120 Sun Tiger waterstone after levelling out the scratches and dips from the hand grinder...at this stage the tang geometry can still be adjusted with a file.
the finish created by a 120mesh/120micron (extra-extra-coarse) DMT diamond stone, the edge is almost at zero now, about a fourth of a mm.
once the basic geometry is established, this is the official "coarse" stage of the polish, working perpendicular to the blade with a 220mesh/60micron (extra-coarse) DMT diamond stone until all the diagonal lines of the rough shaping are erased...this is also the first stone to touch the mune (spine) after the drawfiling before yaki-ire.
moving to a 325mesh/45micron (coarse) DMT diamond stone and working diagonally until the perpendicular scratches are erased ...the polished area should extend along the tang to include the area where the habaki will cover.
...i usually stop at this stone or the 600mesh/25micron (fine) DMT stone and move to creating the rest of the knife...the next step will be to build the habaki...
Sun Tiger used to make these as well...hand cranked grinding wheel (circa? Anyone know?) until i find a good 50 or 80 grit stone, this is the best human-powered way of knocking off the bulk of the super-hard steel left at the edge after yaki-ire...on this little blade it takes less than an hour to do a decent job with this, more than six with only a 120 grit flat stone!
the finish created by a 120 Sun Tiger waterstone after levelling out the scratches and dips from the hand grinder...at this stage the tang geometry can still be adjusted with a file.
the finish created by a 120mesh/120micron (extra-extra-coarse) DMT diamond stone, the edge is almost at zero now, about a fourth of a mm.
once the basic geometry is established, this is the official "coarse" stage of the polish, working perpendicular to the blade with a 220mesh/60micron (extra-coarse) DMT diamond stone until all the diagonal lines of the rough shaping are erased...this is also the first stone to touch the mune (spine) after the drawfiling before yaki-ire.
moving to a 325mesh/45micron (coarse) DMT diamond stone and working diagonally until the perpendicular scratches are erased ...the polished area should extend along the tang to include the area where the habaki will cover.
...i usually stop at this stone or the 600mesh/25micron (fine) DMT stone and move to creating the rest of the knife...the next step will be to build the habaki...
- Joined
- Mar 25, 2012
- Messages
- 9,286
This is my all time favorite WIP thread !!!
- Joined
- Dec 24, 2012
- Messages
- 2,659
That last picture is stunning. Thanks for the update!
I never knew about the process and order of fitting everything so the polish doesn't get messed up. It makes perfect sense but I guess the thought never crossed my mind. Great info!
I never knew about the process and order of fitting everything so the polish doesn't get messed up. It makes perfect sense but I guess the thought never crossed my mind. Great info!
Last edited:
- Joined
- Jan 2, 2014
- Messages
- 297
this important piece of nihonto hardware is made specifically for each blade and is as complex as making a custom fit piece of jewelery...the function of habaki are three-fold; the primary purpose is to secure the blade in the wooden scabbard without any pressure on the blade itself, the secondary is to provide a solid shoulder against which to mount the handle and guard, and the tertiary is to provide a stiffened flex zone across the transition from tang to blade and decrease the chance of failure at that critical intersection.
a standard habaki is fabricated from two parts; the jacket, which appears to be the entire habaki, and the machigane, a small compound triangular prism shaped wedge that closes the gap where the hamachi bridges the edge and the nakago no hagata of the tang...most of the habaki is formed by forging, the final adjustments by filing, and the joining of the two parts by soldering or brazing in a charcoal forge...i decided to try a traditional Japanese fired copper patination technique which i have only seen on one antique habaki to date, hi-do (緋銅, fire copper), which is accomplished by heating copper in a reduction atmosphere and immediately transferring it to very hot water until cool...the process adds some complexity to the finishing of the habaki but was well worth it for the intense colours it will bring to the finished piece...
view the habaki making process in much more detail here: islandblacksmith.ca/process/making-habaki/
Forging the Blank
A strip chisel cut from a reclaimed high voltage electrical bus bar, a source of very pure of copper.
Hot forged into a bar of proper dimensions this will likely yield enough to make two small habaki.
Cold forging out the taper in both directions from the spine (top to bottom, tang to blade) and leaving the thicker area above the mune intact.
Filing & Shaping
Starting the notch for the munemachi is the most important step as filing it later is much more troublesome.
Using a chisel to remove it from the rest of the bar and cold forging the second side to match the first.
This habaki will have a slight curve at the front, but there is plenty of excess metal here just in case. This "butterfly" is still pretty rough, but there is more forging to do after bending yet.
Using a tapered round punch on its side gives some radius to the inside of the mune. Concaving it slightly in along its length as well helps prevent it rocking on a high centre when the sides are bent up. Because it has been forged quite a bit already, this is as far as it will be bent before a second annealing cycle.
Bending & Fitting
This is the second round of annealing during the bending process, the habaki has already taken on much of its final shape and mainly needs to be thinned and adjusted at this point.
Most of the (cold!) forging is done well back from the machi to avoid hammer contact with any part of the blade.
Cold forging the munemachi from a scrap that was cut off the bottom of the habaki.
A dry fit after filing it to shape, showing how the munemachi will sit against the tang and the hamachi. The habaki will not be bridged by the munemachi all the way to the front which will allow the edge to flow out of it.
Soldering & Finishing
The machigane in place before flux and solder are placed inside. A rusty steel wire provides pressure to the assembly, does not tend to stick to solder itself, and in this case makes a useful stand.
When soldering in a charcoal forge, the air must be kept low and the piece placed away from the blast enclosed in a charcoal "oven" to create a reducing atmosphere.
After cooling slowly to ambient temperature avoids thermal shock that could cause the solder and base metal to pull away from one another, the copper has a layer of black copper oxide, as beautiful as it is, it is very brittle and would not stay intact during the final forging.
In this case, a file was used to clean off the black copper oxide and create a subtle yoko-yasuri pattern. Then the habaki was reheated and very quickly transferred into hot water with a trace of borax in it. This type of fired copper is called hi-do (緋銅, fire copper), the technique causes stable red copper oxide to form instead of the brittle black oxide. The copper in the photo is fully cool, though it looks as though it is still glowing a beautiful red orange colour.
The red oxide does not break off when forged and the habaki can be work hardened as usual, stretching it out to fit tightly in place. The fit at the mune machi showing how the slightly rounded hira/kaku mune style I am calling komaru mune continues into the habaki, rather than having the usual peaked iori mune shape. The habaki should follow the shape of the spine smoothly as it will rest there for drawing from and inserting into the saya.
The final area to work with files is the shoulder that sits against the seppa, it should be square and flat, and should be at 90 degrees to the mune at the munemachi.
Waterstones are used to flatten and polish the shoulder, and usually the rest of the piece, but in this case the red oxide hi-do is the desired finish.
Polishing with fine stones and charcoal is usually saved until after the tsuka and saya are made, but in this case the patina is already in place and must be carefully preserved during the other stages. Ibota wax is hand buffed onto the surface with cotton cloth to deepen the colour and provide a glossy layer of protection.
...view the habaki making process in much more detail here: http://islandblacksmith.ca/process/making-habaki/ ...the next steps will be to make the seppa and then tsuka...
a standard habaki is fabricated from two parts; the jacket, which appears to be the entire habaki, and the machigane, a small compound triangular prism shaped wedge that closes the gap where the hamachi bridges the edge and the nakago no hagata of the tang...most of the habaki is formed by forging, the final adjustments by filing, and the joining of the two parts by soldering or brazing in a charcoal forge...i decided to try a traditional Japanese fired copper patination technique which i have only seen on one antique habaki to date, hi-do (緋銅, fire copper), which is accomplished by heating copper in a reduction atmosphere and immediately transferring it to very hot water until cool...the process adds some complexity to the finishing of the habaki but was well worth it for the intense colours it will bring to the finished piece...
view the habaki making process in much more detail here: islandblacksmith.ca/process/making-habaki/
Forging the Blank
A strip chisel cut from a reclaimed high voltage electrical bus bar, a source of very pure of copper.
Hot forged into a bar of proper dimensions this will likely yield enough to make two small habaki.
Cold forging out the taper in both directions from the spine (top to bottom, tang to blade) and leaving the thicker area above the mune intact.
Filing & Shaping
Starting the notch for the munemachi is the most important step as filing it later is much more troublesome.
Using a chisel to remove it from the rest of the bar and cold forging the second side to match the first.
This habaki will have a slight curve at the front, but there is plenty of excess metal here just in case. This "butterfly" is still pretty rough, but there is more forging to do after bending yet.
Using a tapered round punch on its side gives some radius to the inside of the mune. Concaving it slightly in along its length as well helps prevent it rocking on a high centre when the sides are bent up. Because it has been forged quite a bit already, this is as far as it will be bent before a second annealing cycle.
Bending & Fitting
This is the second round of annealing during the bending process, the habaki has already taken on much of its final shape and mainly needs to be thinned and adjusted at this point.
Most of the (cold!) forging is done well back from the machi to avoid hammer contact with any part of the blade.
Cold forging the munemachi from a scrap that was cut off the bottom of the habaki.
A dry fit after filing it to shape, showing how the munemachi will sit against the tang and the hamachi. The habaki will not be bridged by the munemachi all the way to the front which will allow the edge to flow out of it.
Soldering & Finishing
The machigane in place before flux and solder are placed inside. A rusty steel wire provides pressure to the assembly, does not tend to stick to solder itself, and in this case makes a useful stand.
When soldering in a charcoal forge, the air must be kept low and the piece placed away from the blast enclosed in a charcoal "oven" to create a reducing atmosphere.
After cooling slowly to ambient temperature avoids thermal shock that could cause the solder and base metal to pull away from one another, the copper has a layer of black copper oxide, as beautiful as it is, it is very brittle and would not stay intact during the final forging.
In this case, a file was used to clean off the black copper oxide and create a subtle yoko-yasuri pattern. Then the habaki was reheated and very quickly transferred into hot water with a trace of borax in it. This type of fired copper is called hi-do (緋銅, fire copper), the technique causes stable red copper oxide to form instead of the brittle black oxide. The copper in the photo is fully cool, though it looks as though it is still glowing a beautiful red orange colour.
The red oxide does not break off when forged and the habaki can be work hardened as usual, stretching it out to fit tightly in place. The fit at the mune machi showing how the slightly rounded hira/kaku mune style I am calling komaru mune continues into the habaki, rather than having the usual peaked iori mune shape. The habaki should follow the shape of the spine smoothly as it will rest there for drawing from and inserting into the saya.
The final area to work with files is the shoulder that sits against the seppa, it should be square and flat, and should be at 90 degrees to the mune at the munemachi.
Waterstones are used to flatten and polish the shoulder, and usually the rest of the piece, but in this case the red oxide hi-do is the desired finish.
Polishing with fine stones and charcoal is usually saved until after the tsuka and saya are made, but in this case the patina is already in place and must be carefully preserved during the other stages. Ibota wax is hand buffed onto the surface with cotton cloth to deepen the colour and provide a glossy layer of protection.
...view the habaki making process in much more detail here: http://islandblacksmith.ca/process/making-habaki/ ...the next steps will be to make the seppa and then tsuka...
Last edited:
Kohai999
Second Degree Cutter
- Joined
- Jul 15, 2003
- Messages
- 12,554
The waxy excretion of a Japanese Cicada used to build its nest. It smells bad.:barf:
Picked up ibota and a Japanese burnishing needle years ago....but I like buffers better.
Best Regards,
STeven Garsson
- Joined
- Jan 2, 2014
- Messages
- 297
@STeven the stuff i have isn't particularly smelly, perhaps the processing varies...buffers are certainly quicker!
i have heard that elsewhere, but i think they are not cicada...commonly called ibotaromushi (イボタロウムシ, "ibota larvae insect") and found only on the ibota tree, aka Ligustrum obtusifolium, a type of privet...in my experience cicada are found on many types of tree in Japan...
a little more digging...
seems the latin name may be Ericerus pela: http://www.hfri.pref.hokkaido.jp/zukan/konchu/00data/kamemusi/kaigara/ibotaro/note.html
photos of the wax on the tree: http://www.geocities.jp/kounit/saizikidousyokubutu/kontyuu/sonota/ibotaruumusi/ibotaroumusi2.html
are you still putting that migaki and ibota to good use somehow from time to time?
i have heard that elsewhere, but i think they are not cicada...commonly called ibotaromushi (イボタロウムシ, "ibota larvae insect") and found only on the ibota tree, aka Ligustrum obtusifolium, a type of privet...in my experience cicada are found on many types of tree in Japan...
a little more digging...
seems the latin name may be Ericerus pela: http://www.hfri.pref.hokkaido.jp/zukan/konchu/00data/kamemusi/kaigara/ibotaro/note.html
photos of the wax on the tree: http://www.geocities.jp/kounit/saizikidousyokubutu/kontyuu/sonota/ibotaruumusi/ibotaroumusi2.html
are you still putting that migaki and ibota to good use somehow from time to time?