Review: Hiromoto 240 mm AS gyuto

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mark76

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When I first got into Japanese kitchen knives, the Hiromoto AS (Aogami Supersteel) gyuto was hard to ignore. A lot was written about it on forums and it was generally described as a great introduction to Japanese kitchen knives. The knife was not described as flawless: I read reports about a handle that did not fit well and the knife was reportedly a bit thick behind the edge. Nevertheless it was one of the cheapest knives sporting Aogami Supersteel.



Only about a year ago I decided to get one. One of the reasons is that this knife would cease to be made. The owner of Hiromoto company would retire soon and he did not have a successor. And the knife appeared to be even more of a classic than I had realized. It had actually made it into the http://www.wsj.com/articles/SB10001424053111904716604576546621007499618]Wall Street Journal[/url], where it was described as a “timeless treasure”.


First impression

When I received the knife, I was pleasantly surprised. The fit and finish of the knife was more than ok. The handle fit the knife well and the bolster made a nice transition from the handle to the blade. There were no gaps or even rough spots at all. The spine of the blade had not been rounded, but chamfered a bit. The choil had not been chamfered, but there were no sharp edges.



The blade grind was another surprise. The knife was thinner behind the edge than I had expected based on the reports I had read. The knife also had an interesting geometry. It was pretty asymmetrical: nearly straight and flat on one side and steep, like in a full flat grind, on the other.



In practice this worked out well. When I tried the knife on some veggies, it hardly wedged. Only on vegetables like winter carrots and white winter radish I could notice some minimal wedging.

The knife was also thinner than I had expected. Its spine is 2.6 mm wide above the heel. The spine tapers only a little bit until a couple of centimeters before the tip, but then it tapers down to 0.9 mm one centimeter from the tip. This isn’t the thinnest tip I’ve seen, but it works ok for the finer work.



The knife looked a bit bland with its black pakkawood Western handle and its hardly noticeable transition from the jigane (the soft stainless cladding) to the hagane (the core AS). But I got this knife for its steel and its performance, didn’t I? Well...

Dave Martell has popularized the “spa treatment” for Hiromoto knives. Dave’s spa treatment involves thinning the blade and then etching it, so the distinction between the jigane and the hagane becomes more prominent. And it involves a rehandling of the knife. The spa treatment to my Hiromoto was given by Tim Johnson of Blackstone Knife and Tool.


Second impression

My second impression was one of horror. The knife had been shipped. This is the result of the USPS treatment.



Thanks to a nice US knife dealer the knife was completely straightened again and this is the knife when I received it back.



The new handle is made of maple burl and black painted Hawaiian silky oak. A nice thing is that even after the rehandling the balance point is about 2 centimeters in front of the bolster.

After thinning the knife cut even better than before. Sometimes people say their knife “falls through” food. I now know what they mean. The weight of this knife (227 grams) certainly helps.



An important reason for getting this knife was that it has a core of Aogami Supersteel. Over the past years I’ve used knives made of many different types of steel: various types of stainless, semi-stainless and carbon steel. But if there is one steel that is the best in terms of both taking and holding an extremely polished edge, it’s Aogami Supersteel. And Hiromoto got their heat treatment of this steel right.

I sharpened the knife with my Shapton Pro stones up to 30K. Normally these 30K stones are for straight razors only. On many kitchen knives I do not notice any improvement anymore after 8K and I seldom notice any improvement after 15K. But I did on my Hiromoto knife and I continued stropping with 0.25 micron and 0.1 micron diamond sprays. The Hiromoto was now definitely the sharpest knife I’d ever felt. It just needed to touch a tomato to split the skin. Who wants a toothy edge when you can get it this sharp? :D

Needless to say that the Hiromoto easily dealt with everything I threw at it: hard veggies, soft veggies, proteins. Only with stuff that required delicate tip work it was not optimal due to its tip that is slightly thicker than on some other knives.



I also like the profile of the Hiromoto, which I’d describe as all-round. It has a nice flat spot at the heel, but also sufficient belly for rock chopping.



Food release is not great on this knife, as is the case with most other thin knives.


Conclusion

The Hiromoto AS gyuto is not just a cheaper knife sporting Aogami Supersteel. It is a well-made knife with a good fit and finish that cuts fine. And if you decide to give it the spa treatment, you’ve got a knife that is a great looker and cuts very well. They are not made anymore and due to their popularity they are even hard to get second-hand. But if you can lay your hands on it, I highly recommend it.


Factsheet

 
I have also posted this review at my blog, where you can read this review and others nicely formatted.

All comments are welcome! Did I miss something important, do you have another opinion or do you agree? Please let me know. I also write these reviews to learn.
 
Fantastic review as usual! Shame I ended up missing being able to get a hiromoto, and I'm not really desperate enough to go a certain other route...
 
My Hiromoto was great in every way except I did not experience the flat spot that the OP mentions. My knife had an almost full belly profile where there wasn't more than one inch that would touch the board at any given time. I loved the knife but could not get used to the profile. My cuts would accordion on almost everything I did. It did not suit my cutting style very well. I really had to rock my push cuts to fully cut the food. It is not the knife's fault and I had a great specimen, but it was just not the knife for me. Glad the OP loves it as much as I wanted to love mine.
 
KC, I've read that the Hiromoto has changed quite a bit since some time ago. Not only the profile, but also the geometry. As I wrote, mine was pretty asymmetrical (which it apparently wasn't before) and quite thin behind the edge. It hardly needed any thinning.

I see something has gone wrong with the link to the Wall Street Journal article. The correct link is: http://www.wsj.com/articles/SB10001424053111904716604576546621007499618
 
It has been my understanding that these knives are no longer available. However, CKTG has the 150mm petty and 240mm gyuto. Are these the same knives?
 
It has been my understanding that these knives are no longer available. However, CKTG has the 150mm petty and 240mm gyuto. Are these the same knives?

The smith is still making knives although the range and supply are inconsistent. Seems the 190mm Santuko are readily available and a western handled Honsuki.
 
And two gyutos in monosteel Aus-10, 240 and 270mm, at $117 and 137 including worldwide shipping. I've got the 270mm and it is fantastic knife. Crazy thin, lighter, wider and flatter than the AS. Has a remarkable edge retention.
 
I am somewhat at a loss here. Your drawing of the profile does not in anyway seem to match the actual profile of the depicted knife. Whereas it is pretty obvious from your pictures that the choil of the knife goes straight down and the heel is nice and sharp, the drawing indicates something entirely different – the heel seems to be rounded and the choil comes down at an angle. Further, the profile pictures and the profile drawing seem to be of two different knives. Whereas the pictures show a long flat section, that is not the case in the drawing. Just wondering which represents the actual profile – the drawing or the pictures?

Shouldn’t this BTW be in the Review section?
 
The smith is still making knives although the range and supply are inconsistent. Seems the 190mm Santuko are readily available and a western handled Honsuki.
it is my belief the stock at CKTG is from an older order and that master nagao does not produce most of the tenmi jyuraku knives anymore. some of them can be found still through hidatool as well if you like smaller knives or really big ones.

I own a 240mm hiromoto aus-10 and I'd cosign benuser's comments about that knife, steel and master nagao's treatment of it any day. almost as much of a pleasure to use as my ginsanko tenmi jyuraku. I am planning to get one of these AS gyutos from CKTG so I'll be sure to do a review of it because people seems to be quite worried about the reputation of the vendor and the quality of the stock he carries, as Hiromoto is not known for f&f.
 
I had a Hiro 240 AS that Dave M rehandled (but did not have a full spa treatment) and it was a good knife. But not a great knife. The handle was the best part. With apologies to Bernard, any description of the HIro has to include "for the price...."

And soup, I don't think that people are "quite worried" about the reputation of the vendor cited. It's quite established.
 
idemhj, you have a sharp idea. Instead of a picture of the Hiromoto profile, I accidentally posted one of a knife I'd reviewed before (a custom Haburn gyuto). Here is the correct Hiromoto profile, which shows a bit of rounding towards the heel:



Here is the photograph I used to produce the line drawing of the profile:

 
idemhj, you have a sharp idea. Instead of a picture of the Hiromoto profile, I accidentally posted one of a knife I'd reviewed before (a custom Haburn gyuto). Here is the correct Hiromoto profile, which shows a bit of rounding towards the heel:



Here is the photograph I used to produce the line drawing of the profile:


Okay, now I get it. That looks good
 
Hiromoto was my first Japanese knife and I just loved it from the beginning. Yes, F&F doesn't have the best reputation, but mine was finished very well. Personally I liked the handle a lot myself, I have smaller hands, and its handle shape fitted very well in my hand. My only complaint was that choil was strait and had no curve to it. After prolonged usage my index finger was sore. Knife had a beautiful patina, wasn't very heavy and very light, somewhere in the middle, and I found the hight of the blade just right for me. The cladding is very soft very prone to scratches.

After a year I sold the knife, and now I regret it. There was something special about that blade.
 
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I just recently sold my heavily tuned Hiromoto AS 240 Gyuto.

At first I just bought it because I heared that they'll no longer being produced to I quickly bought one from Koki (wasn't that expensive though..)

Was pretty disappointed at first. Ok but not good F&F (sort of in the range as my other Yo-Gyutos at the time...Masamoto HC, Carbonext, Tojiro DP3 HQ) and quite medium performance as well (like the Masamoto HC too). So I had both thinned by a local specialist (does really good work IMHO)... the Masamoto with a real laser grind and the Hiromoto with a sort of laserish but user friendly grind, a little convex, too.

Used it a couple of time and found it was an amazing knife. Then had Greg rework the handle and etch the blade and it came out pretty good I think:

http://wabocho.blogspot.de/2015/06/hiromoto-as-240mm-gyuto-modification.html

But... Yo-Gyutos are quite simply not my preference and so it wasn't used at all... so I sold it.

But after tuning, I think the Hiromoto is a very capable knife. Before thinning, it's not so great...
 
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