Summary: An economy knife that performs well on its primary task of getting and staying very sharp, but with some shortcomings.

I purchased one of these Japanese knives from Carbatec to see how it performed. The following are my thoughts on the knife.

Without knowing how they would go on quality and performance, the price (just A$64 for the one I purchased) made them sufficiently attractive to take a punt and give these knives a test run. Yes, that is more than the cost of a utility knife from Ikea, but in my experience those are already blunt by the time you get them to the checkout counter : ~}

The knife I purchased was the small 105mm long, double bevelled, utility knife (Ko Bōchō : small knife), which is not that dissimilar to small western knives other than the depth of the blade, particularly towards the heel, which helps keep the cutting hand away from the food that is being sliced. But, the construction and properties of these Japanese knives are very different from western knives. There is enough readily available information out there on the general nature of Japanese knives for me to not have to go into that here.

Here is the knife as it arrived:


The Carbatec listing indicates that the knife had been made with hand forging techniques using high carbon white steel laminated between rust resistant cladding. The cladding (probably stainless steel) will be stain resistant, but they rightly warn that susceptibility to surface rust is an unavoidable attribute of high carbon steel knives. IMI, this is not an issue if you wash or wet wipe and dry as you go.

A close inspection found various shortcomings with the knife, but on the key task of taking a very sharp edge it performed very well
straight out of the box. The following video shows how well it passed my cigarette paper cutting test.



As you can see the knife cut through the thin cigarette paper with ease. This is a very demanding test, just try it out on any knife you have that you think is sharp.

The second thing a good knife does is keep its sharp edge after repeated use. I used the knife daily for a month cutting fruit and vegetables. I then repeated the cigarette paper cutting test after a month of use. The result is shown in the above video, as that was in fact taken after a month of daily use; there was so little difference in its performance between before use and after a month of use that I have just posted the after use video.

So, a good performer on the basics. The other positive I should mention is that the blade was true to the handle; they arent always in the economy knives.

There were quite a few shortcomings that are typical of economy knives. Probably the most obvious is the poor finish on some areas of the knife. These included the grind marks on the choil (heel) and along the spine.


Of these, the heel grind (or lack of it) is the most problematic as the fingers on the cutting hand are often against this area of the knife. It is not much effort to grind and polish the choil smooth yourself, but it will remove the natural scale from the surface. If you do so, I also suggest you also ease off the corner between the cutting edge at the heel with a small radius as that will save a few nicks to your hands when washing and drying the knife, which you should do promptly after every use.

Another quibbles is the partially exposed drill hole in the handle where the tang goes into the handle. This is a trap for food and is unhygienic. That needs to be sealed to prevent that. Some epoxy will do it.



My final quibble is the finish on the area where the cladding has been ground on the bevels. A minor matter in terms of the functioning of the knife, but it offends me in terms of authenticity. In the photos above or below you can see quite a distinct change in the surface appearance of the hard edge steel and the soft metal cladding. The cladding looks matt, while the hard edge steel is bright in comparison. This is typical of the appearance of knives made in the traditional manner that have a cladding of soft iron. However, from experience I know that knives which are clad in soft stainless steel do not look this way. The surface appearance of the cladding on this knife is an affectation. Closer inspection revealed coarse grind marks that are masked with sandblasting, or acid etching or a matt coating of some sort.

When I ground this away with waterstones I found, as expected, that the matt appearance disappeared to be almost indistinguishable from the cutting steel. So what? Well, the exposed surface became quite reactive to the natural acids in fruit; not so much by way of tarnish but it produced a distinct tangy metal smell and taste. I have experienced this before in Japanese knives that have been etched to accentuate a Damascus pattern. An application of a metal lacquer will masks this. I have done this but dont know what the risks might be of having this in contact with food.

I should also comment on the grind on the knife, as received. The grind on the primary bevel was ordinary to say the least, but the knife came with a very fine micro-bevel which gave it its very good cutting performance. Unless you looked for it you may not see this micro-bevel that is only microns wide. This shows up when the knife is held at the critical angle to a strong source of light, which will make it look much wider than it is.



Maintaining this micro-bevel is a good way to keep this knife sharp. I sharpen/hone my J-knife edges on Waterstones up to at least #4,000 grit, and usually much higher. I find the higher I go the longer they stay sharp.

I also stain and seal any knife handle that comes in blond wood, (probably Ho wood) in the case of this knife. If left unsealed it will get stained during use, but not in a pleasant way, IMO. Here it is now with the treated handle, the second from the right.



I did try to get the name of the maker of this knife from Carbatec, but they havent come good on that. I think it is a Yamashin (see here), but Im not confident about deciphering the kanji characters myself, but here they are in case someone else can help.



So, if you havent yet experienced Japanese hand forged kitchen knives you might like to consider this economical option. Despite its shortcomings, which can be overcome with a little attention from yourself, it performs well at cutting and staying sharp.


Warning: These knives come very sharp and will cut you if not used with care.

Also, the transition from stainless steel blades (that invariably end up blunt most of the time and then get used with force to get the job done) and Japanese high carbon steel knives that cut with minimal effort can take some getting used to for those that have had years of experience with stainless steel knives. And, the very hard and brittle steel in the cutting edge of these high carbon J-knives is less tolerant to impact against hard materials. I have found that this has not always been understood by my friends and family members who have been given these knives as gifts, despite my best efforts to educate them in their proper use. Then they get the full re-education program when they return them to have the nicks removed : ~}