Visiting Sukenari Hamono, Apr 2016

Visiting Sukenari Hamono, Apr 2016

Posted by James Zhang on 2nd May 2016


We all know Sukenari offers exceptional knives, but there isn't much information on the Internet about them. During the last trip I went to visit Sukenari Hamono at Toyama Prefecture in the Hokuriku region. I am thoroughly impressed by Master Hanaki’s way of perfecting his knives and his philosophy of knife making, so I think it is good to write something about Sukenari.

The Drive

The Hokuriku Express Way runs along Japanese Alps range. It was a very pleasant 2 hours drive from Sanjo to Toyama, as the cherry blossom was in full bloom. The mountain view was quite spectacular when we reach the Toyama exit, and it didn’t take long before we reach Sukeanri.

Fig 1: The Hokuriku Express Way, Toyama exit. The Alps at the back is quite stunning.

Fig 2: The front sign of Sukenari Hamono.

The Workshop

After a short meeting with the president of Sukenari, Master Nobuo Hanaki, we walked through their workshop. Sukenari’s workshop is clean and tidy; they have the usual set up like the power hammer / charcoal oven station; the big water grinder, belt grinder and hand sharpening area. They also have some very special machines, for example a stamping machine that marks their knives. I often see either laser engraving or hand engraving but this is the first time that I see this stamping machine.

Fig 3: A logo stamping machine at Sukenari, they use the metal seal engraved with Kanji to stamp the pre-heat treated blade. 

Fig 4: The metal seals used at Sukenari, from right to left: ZDP 189, Ginsan, High Speed Steel, Super Steel, Fire Forged.

While I can’t show you the pic but I can say that I have seen some very famous brand names among these seals :) Another very promising approval for Sukenari knives. I also saw a new stamp (steel) from them, I will keep my mouth shut for now.

Fig 5: A new product of Sukenari, left Kanji reads: Powdered Steel; right kanji reads: Registered Sukenari.

Sukenari is the only professional knife manufacturer in the region so basically everything is done in-house. They have 4 people working full time doing forging and sharpening. I asked Master Hanaki if recurring is difficult and he joked “you’d be lucky to get one person that is talented and passionate about knife making out of five apprentices.”

Fig 6: One of the four knife makers at Sukenari demonstrating how to rough shape a Gyuto from a blank.

The Sukenari Honyaki

Many of you probably have some questions about the honyaki that Sukenari has on offer:

“Why they only offer honyaki in white 1 steel?” “Why their honyaki looks very nice yet offered quite cheap?” “Is their honyaki water quenched or oil quenched?”

Well I had these questions in my mind for a long time and I got the answers. According to Master Hanaki, in order to make a true honyaki knife, it has to be done in the most traditional way using the steels that is closest to Tamahagane (the steel used for Japanese Samurai swords 玉鋼). So for Sukenari honyaki, that means it has to be hitachi White 1 steel, water quenched. I was privileged to watch him forging a honyaki. He told me the clamps that he use were made by himself, using white 1 steel as well, joked that they are “honyaki clamps”.

Fig 7: Master Hanaki demonstrating and explaining how to forge a honyaki blade.

Fig 8: Master Hanaki demonstrating how to forge a honyaki blade (power hammering).

Fig 8: Master Hanaki demonstrating how to forge a honyaki blade (hammering on anvil).

One very important step that he did was burying the forged blade into the straw-ash, he said this was a vital step in preventing the hot blade from oxidation and carburization.

Fig 9: Master Hanaki buries a hot honyaki blade into the straw-ash, preventing oxidation at the surface of the blade.

Once the knife is set, it is then cladded with mud

Fig 10: The mud used to clad a honyaki blade, in order to have differential heat treatment. 

The next photos shows a heat treated honyaki blade. According to Master Hanaki, the water in the tank below used for the water quenching is more than 10 yrs old. It is another secret for his mizu-honyaki knives, and new water is not as good as this old, more stable water. I don’t know the true reason behind this but I suppose it is just similar to adding water to fish tank: fresh water has some sort of unwanted chemical that is not good to the water quenching process. 

Fig 11: A deferentially heat treated honyaki knife, the water in the tank below is over 10 years old, apparently the age of water reduce the chance of failure during water quenching process the honyaki knife.

Mizu-honyaki is heat treated one-by-one at Sukenari, each time only one blade goes into a tiny little chamber to heat up before gets di pped into water. So unlike modern aircooled steels that could be heat treated in a big batch, the mizu-honyaki knives is done in the most traditional, and time consuming way. I have full confidence in their honyaki blades are as good if not better than any honyaki knives produced elsewhere (more proof next).

So why they are priced lower (compared to other brands)? I suppose this could be explained by the fact that everything is made in house instead of contracting someone, and been quite isolated from other knife making region, they are less affected by “what others are doing / pricing” and more focused on what they do: making great knives.

About Master Hanaki and his knife making philosophy

I see Master Hanaki as more of a knife maker than a businessman. You probably have realized that Sukenari offers A LOT of different steel type. From traditional steel such as the Hitach Aogami (Blue), Shirogami (White) and Aogami Super (Blue Super, AS), to modern steel like Ginsan, VG10, ZDP189, ZDP 4, Super X and more recently, YXR7. Master Hanaki was really into the core of different types of steel. I said so because he actually gets all his knives tested by a 3rd party hardness testing lab, and their claims of hardness is damn correct. 

The following example shows why I was so impressed with Sukenari. Master Hanaki gave me two HRC test charts, the first chart shows the HRC reading between 60.4 to 61.1 for a stamped, sanmai Ginsan Gyuto. 

Fig 12: Hardness (HRC) testing and steel structure photo for a stamped Sukenari Ginsan Gyuto, showing the hardness ranges from 60.4 to 61.1.

The second chart is a forged Ginsan Gyuto with Damascus sanmai construction, with the HRC reading ranges 61.6 to 62.9.

Fig 13: Hardness (HRC) testing and steel structure photo for a forged Sukenari Ginsan Gyuto, showing the hardness ranges from 61.6 to 62.9.

These charts show that

  • 1.Sukenari actually cares about how well their heat treatment is, and if they are not satisfied with the reading, they will find ways to improve.
  • 2.The hardness chart, the 100x magnification of the internal steel formation and the 400x (not shown here) demonstrated the forging process makes the steel more even with less impurity (unwanted particles and trapped air bubble), which will lead to a stronger edge due to less internal stress and less chance of failure caused by impurity.
    The forging process actually improves the hardness of the core steel by an average of 1 unit (presumably with the same HT), which is quite significant.
  • 3.This also helped in explaining a questioned asked by Tanner (tJangula) in this thread,  post #5 Q: “I'm curious about how there may be a stock removal and forged version of the same knife….?” A: harder and more uniform :) 

Another super impressive thing is how they deal with Aogami Super: they actually water-quench the AS steel to its maximum potential: HRC 66 – 67. Doing so is very risky, Master Hanaki told me the failure rate of the AS Damascus blade is close to 70%, and they struggle to make a profit out of this line; but then this is what the customer wants so they will do it, without any compromise. This is the reason I say Master Hanaki is more like a knifemaker than a businessman, and I am humbled to be able to carry Sukenari knives.

Fig 14: Hardness (HRC) testing and steel structure photo for a forged Sukenari Aogami Super (Blue Super) Gyuto, showing the hardness ranges from 65.4 to 67.0; and the core steel under 400x magnification is extremely even. 

(more charts at the end of the blog).


The only thing I wish was the day could go a bit longer as the last part of the visit was having some much needed (and FREE! lol) one-on-one tutorial with a true master :D Oh actually, I scored that blade I was sharpening! 

Fig 15: Me enjoying some sharpening tutorial from Master Hanaki.

And…. Of course there is the lovely happy ending of the day hosted by Master Hanaki.

Fig 16: Sashimi dish of the dinner hosted by Master Hanaki, I can only say there is some tuna, some other fish sashimi, some prawn and the famous Toyama white prawn / baby squid ;p

That is it, thanks for reading!


Appendix: more HRC Charts