• If you have bought, sold or gained information from our Classifieds, please donate to Kitchen Knife Forums and give back.

    You can become a Supporting Member which comes with a decal or just click here to donate.

WTS Yasha Yukawa Tamahagane Warikomi Gyuto 240mm

Kitchen Knife Forums

Help Support Kitchen Knife Forums:

Bensonhai

Well-Known Member
Joined
Nov 4, 2021
Messages
138
Reaction score
402
Location
Orange, Ca
This knife is #2 in his new series of knives called Kanayago. This is the 1st 240mm Gyuto of that series.

Model: Gyuto
Blade length: Approximately 240 mm
Blade material: Nittoho Tatara Tamahagane
Construction method: Warikomi
Blade Thickness: 3.7 mm at the heel
Finishing method: “Chiirui Kuro-uchi” Hand polished on natural whetstones

I had my friend, Franki Alo make a YouTube video.


You can also see the exact knife on Yasha's website. Kitchen Knife Gyuto240mm - Yasha Yukawa

Looking to get $2000, down to $1900
Screenshot_20220327-122826_Gallery.jpg
Screenshot_20220327-122823_Gallery.jpg
Screenshot_20220327-122819_Gallery.jpg
Screenshot_20220327-122815_Gallery.jpg
 
Last edited:

Forty Ounce

Senior Member
Joined
Mar 30, 2019
Messages
326
Reaction score
476
I'm not sure, but I think I'm seeing delam on the front and cladding at the edge on the back.. would you mind checking this to confirm?
 

Bensonhai

Well-Known Member
Joined
Nov 4, 2021
Messages
138
Reaction score
402
Location
Orange, Ca
I'm not sure, but I think I'm seeing delam on the front and cladding at the edge on the back.. would you mind checking this to confirm?

Straight from Yasha

"It's not really a delamination, Technically a delamination would leave a hollow pocket, which surely is not good.
Making steel and laminating by hand, do leave some character that may not be valued by somebody used to mass produced factory made steel. The same goes for any craft.
To produce great steel we need to take some risks, and not "over cook" it. So sometimes like in this case, it may leave a mark.
I would rather call this a mark of hand crafted steel, with no functional disadvantage.
It is a matter of taste and appreciation of unavoidable quirks of something truly crafted by hand."
 

ptanks15

Well-Known Member
Joined
Feb 4, 2022
Messages
71
Reaction score
33
Location
United States
Straight from Yasha

"It's not really a delamination, Technically a delamination would leave a hollow pocket, which surely is not good.
Making steel and laminating by hand, do leave some character that may not be valued by somebody used to mass produced factory made steel. The same goes for any craft.
To produce great steel we need to take some risks, and not "over cook" it. So sometimes like in this case, it may leave a mark.
I would rather call this a mark of hand crafted steel, with no functional disadvantage.
It is a matter of taste and appreciation of unavoidable quirks of something truly crafted by hand."
So it's a delam that he'd rather call something different? Or is he saying it's definitely not a delam?
 

Corradobrit1

Senior Member
Joined
May 2, 2015
Messages
4,997
Reaction score
4,048
Question is can it be felt with the fingernail? If yes, I consider that a problem. If not, then it could be carbon migration at the core cladding steel interface. Another certified swordmaker's blades, well known on KKF, often have this black line along portions of the lamination line.
 

MSicardCutlery

KKF Sponsor
Joined
Feb 28, 2022
Messages
315
Reaction score
715
This is just my opinion, but it looks like a delamination to me. To my knowledge carbon migration doesn't look that even or have such a clearly defined boundary. If you look at pictures of stainless clad carbon steel blades sometimes you see the dark waves that are produced by carbon migration, they're wispy and hamon-like.

The Japanese have a list of blade imperfection types, and a three tiered ranking system for them, usually applied to swords. I forget the name of this particular form of imperfection, but on a full sized blade it's regarded as minor, and still permits for regular use.

If it's closed tight I don't see it being an issue, and it may be, because of the nature of tamahagne, a void that shut and welded, (though usually those a appear white), and completely insignificant. A 10x loupe would tell you one way or the other though
 
Joined
Aug 29, 2018
Messages
1,310
Reaction score
1,654
When I was polishing a yasha Yukawa, the lamination lines would rust preferentially, or patina. When I would polish over long periods of time without using a rust inhibitor, black latina would form that looked exactly like what is shown on the knife. I don't think it's delamination to the full extent that is being discussed, and I know yasha really trys to make things solidly welded. Because of the nature of the insane amounts of forge welds, there's going to be some more rusticness especially if he does what is best for the steel edge taking, which is minimizing the temperature used so as to not leak carbon away, or promote too much grain growth. It's a limitation of the medium, of choosing tamahagane.

I can show some pictures of I can find them of a similar line, and how it looks completely polished
 
Last edited:
Joined
Aug 29, 2018
Messages
1,310
Reaction score
1,654
Here are some of the polish pictures. When I didn't let the knife intentionally rust a little bit, the lamination lines were really subtle and hard to see. This is all with uchigumori fingerstones. So I let it patina or rust black at the lines, then used the uchigumori to remove some rust, then we see the removed metal highlight the lines. Before the steel was really quite solid, anyhow, and felt that way too.

If the knife is allowed to sit during polishing
PXL_20210401_203149579.jpg


Then polished again
PXL_20210401_224041375.jpg
PXL_20210331_014733861.jpg
knife2.JPG
PXL_20210401_224017176.jpg
PXL_20210401_224041375(1).jpg


Now yeah, it could be something more from the manufacturing process, and yes I would be more ideal to have more strong welds, but I would like Yasha to err in the side of better edge taking and steel toughness over a higher guarantee of total structural toughness but worse steel and steel activity and color. The knives aren't actually swords anyway, and wrought iron blades too have this sort of stuff, and Kanna as well, especially if you look in their backs, I've seen the steel and iron boundaries have separation. And if you've seen raw billets of iron and steel forge welded, it's a pretty messy looking thing and those outer boundaries are roughest. Because yasha can't just grind away the outer parts so readily as with regular laminated stuff (because tamahagane is expensive, conserve it), he had to toe another fine line. Extra effort too, with keeping a higher carbon content on this knife and fewer chances to squeeze everything as tight as with swords. In carbon content and hardness, it very much felt like a white 1. Not as high as tf, but certainly harder than Hinoura and the white 2 I've tried from Sakai. Comparable to heiji carbon, for instance, which should make sense.

However. The geometry can be super workhorse. . . swordlike, so know that.
 
Last edited:
Joined
Dec 22, 2020
Messages
16
Reaction score
52
Location
Edmonton, Alberta
Good day folks. Given this particular knife is still in my possession, I woke up this morning and prioritized trying to get to the bottom of this. So much so, I prioritized this knife over even making my espresso 😆

Alright, so for my investigative journaling I used a nice high powered light and a hand loupe to see if I could get closer to the main area we have questions about. You will find three pictures attached (1-3) showing the area some believe to be delamination. I'll let those who know more about delamination speak to this, and I'll simply report on my findings. Each picture shows you the area of interest inching ever so slightly closer. In the last picture, I applied some contrast to help show the pits that exist along our troublesome area. I even included a video to try and demonstrate the scale and severity.

To supplement the visual test, I also did a tactile test by running my nail from the shinogi all the way down to the cutting edge across the entirety of the knife's length. Once the nail reaches the affected area, it does immediately feel rougher and the nail does seem to ever so slightly catch. It is very minor, I cannot emphasize enough, but it is there.

Lastly, as a full disclaimer from @Bensonhai, I thought I would also include a picture showing the tip of the knife being slightly bent with some micro-chips.
1.jpeg
2.jpeg
3.jpeg
IMG_6288.jpeg
 

Attachments

  • IMG_6289.MOV
    39.8 MB
Last edited:

Forty Ounce

Senior Member
Joined
Mar 30, 2019
Messages
326
Reaction score
476
Good day folks. Given this particular knife is still in my possession, I woke up this morning and prioritized trying to get to the bottom of this. So much so, I prioritized this knife over even making my espresso 😆

Alright, so for my investigative journaling I used a nice high powered light and a hand loupe to see if I could get closer to the main area we have questions about. You will find three pictures attached (1-3) showing the area some believe to be delamination. I'll let those who know more about delamination speak to this, and I'll simply report on my findings. Each picture shows you the area of interest inching ever so slightly closer. In the last picture, I applied some contrast to help show the pits that exist along our troublesome area. I even included a video to try and demonstrate the scale and severity.

To supplement the visual test, I also did a tactile test by running my nail from the shinogi all the way down to the cutting edge across the entirety of the knife's length. Once the nail reaches the affected area, it does immediately feel rougher and the nail does seem to ever so slightly catch. It is very minor, I cannot emphasize enough, but it is there.

Lastly, as a full disclaimer from @Bensonhai, I thought I would also include a picture showing the tip of the knife being slightly bent with some micro-chips.View attachment 172382 View attachment 172383 View attachment 172384 View attachment 172385
I think we can just call this a dirty weld and not necessarily delamination. Not ideal, especially for a 2k knife, but not the worst thing ever.
 
Joined
Jan 19, 2022
Messages
57
Reaction score
225
Location
Switzerland
I just wonder: how well does it cut? Can it be used in a kitchen like any other Gyuto? It seems to be quite thick and therefore more suitable for "deba-work" or cutting meat. Beautiful knife without any question and yukawa even makes his own steel, but overall more a collerctor's item than a kitchen knife for gyuto use or am I wrong here?
 

Bensonhai

Well-Known Member
Joined
Nov 4, 2021
Messages
138
Reaction score
402
Location
Orange, Ca
I just wonder: how well does it cut? Can it be used in a kitchen like any other Gyuto? It seems to be quite thick and therefore more suitable for "deba-work" or cutting meat. Beautiful knife without any question and yukawa even makes his own steel, but overall more a collerctor's item than a kitchen knife for gyuto use or am I wrong here?
Being the low serial number #2 and the 1st gyuto 240mm of the series...I would think collecting it would make sense.
 
Top