This post continues the series of shopping suggestions tied to Japanese kitchen craftsmanship: after the knives from Kappabashi and Tsukiji, the yanagiba bought from Jikko in Osaka, and the hinoki cutting board, one piece is still missing, probably the most divisive of them all.
In the post on the yanagiba bought from Jikko, I described how, the first time I used it, I cut a finger wiping the blade on a tea towel: intimidated by how sharp it was, I found out the hard way anyway. That anecdote hides a bigger question, one I settled in a single line in the original Kappabashi post: whetstones bought in Japan are “just unnecessary weight in your luggage”, I wrote at the time, suggesting you buy them once you are back home instead. It is an honest conclusion, but also a rushed one. It deserves a post of its own, exceptions included.
First Question: Sharpen It Yourself, or Take It to a Professional?
It is the question no shop will ever ask you, because the honest answer does not always match what suits them to sell.
The case for doing it yourself. Sharpening a knife on a stone is a skill, not a trick: once learned, it stays with you for good, applies to every future knife, and costs nothing for every sharpening after the first, modest investment. For many enthusiasts, learning to handle the stone is part of the pleasure of owning a Japanese knife, not a chore bolted on afterwards: it is the same kind of manual satisfaction as someone who makes coffee with a moka pot rather than a capsule machine. If you bought a knife meaning to keep it for decades, you will have to learn eventually anyway, because no professional sharpening service stays convenient or cheap forever.
The case for a professional. Here a distinction is worth making honestly, all the way through: sharpening a double-bevel knife (a Santoku, a Gyuto) is fairly forgiving of a beginner’s mistakes; sharpening a single-bevel knife like the yanagiba I wrote about is another matter entirely. The asymmetric geometry of a single-bevel blade requires a specific technique, different from the Western one, and getting the angle wrong on a blade the maker has already ground to an extreme thinness means risking ten minutes of ruin for an object that cost the equivalent of an elegant dinner out. This is not a theoretical risk: it is exactly the kind of mistake a beginner makes with enthusiasm.
One thing is worth clarifying, since this post is aimed mainly at people who buy the knife as tourists and take it home with them: professional sharpening in Japan exists and is surprisingly accessible, but it is of limited practical use to you. In Kappabashi, shops such as Kamata offer sharpening by a third-generation “master sharpener” (about 45 minutes per knife, according to several travellers’ accounts), and Jikko’s own showroom in Sakai, the one with the open forge I described in the Osaka post, regularly runs sharpening courses and sessions: these are valuable details if you live in Japan, or return often enough to make use of them, and I imagine some readers of this blog fall into that category, however small. For the vast majority of you, buying the knife on the third day of a two-week trip and using it for the first time only once you are home, the sensible approach stays a hybrid one, but played out entirely outside Japan: practise on a cheap or double-bevel knife, and for the good one find a trusted professional in your own city, keeping only light maintenance for yourself between proper sharpenings.
That is, in fact, exactly what I intend to do. On my first trip to Japan I bought two stones, which currently sit unused in the kitchen: I still have not had the nerve to sharpen my most precious knife myself, and for now it holds its edge admirably well. I will probably try the stones out once the Santoku, being less delicate, starts to lose its bite; for the yanagiba, though, I think that when the time comes I will look for a professional in my own city rather than risk a first attempt on a blade that cost me dearly.
The Stones: A Short Taxonomy
The Japanese sharpening system rests on three grit categories, each with a specific name and a precise purpose.
Arato (coarse grit, under 1000): the emergency-surgery stone. Used to repair chips, straighten a crooked edge, or rebuild the sharpening angle from scratch on a badly neglected knife. It removes a lot of material fast, which also means careless use can do real damage.
Nakato (medium grit, roughly 1000 to 3000): the everyday-work stone. This is where you will spend most of your time, and it is enough on its own to keep a fully functional edge for normal use.
Shiageto (fine grit, above 3000, typically 4000 to 8000 for home use): the finishing stone. It is not for “sharpening” in the strict sense; it is for smoothing and polishing the edge already created by the nakato, getting that near-surgical cutting ability Japanese knives promise.
Beyond shiageto there are even finer stones, up to 10,000, 20,000 and beyond, whose purpose is closer to professional single-bevel blade polishing than any real practical benefit for home use: a fine indulgence for collectors, marginal usefulness for anyone cooking dinner at home.
Two accessory categories are worth knowing alongside this taxonomy: nagura, small soft stones rubbed against the main stone to raise a slurry that speeds up the abrasive action of finer stones, and combination stones, which pair two different grits on either side of the same block (typically a nakato and a shiageto), practical for anyone short on space who does not want to buy separate stones.
Synthetic or natural? Synthetic stones (brands such as King, Naniwa, Suehiro, Shapton) are consistent, predictable, and more than enough for 99 per cent of home use. Natural stones, historically quarried in the Kyoto area (Nakayama, Suita and Umegahata are the names that come up most often), are a different matter entirely: many of the historic quarries are now exhausted or closed, which makes good natural stones increasingly rare, increasingly expensive, and the object of an almost fetishistic collecting culture among Japanese knife enthusiasts. If your goal is an excellent edge, a good quality synthetic stone gets you there without drama. If your goal also includes the appeal of a handmade object with 250 million years of geological history behind it, natural stone is a world of its own, with prices that start in the low hundreds and climb quickly from there.
Stones for Flattening Stones (Yes, Those Exist Too)
Here is a detail no shop mentions unless you ask directly: sharpening stones wear unevenly with use. The centre, the part the blade passes over most often, dishes slightly, and a concave stone no longer sharpens correctly: it creates an inconsistent angle along the length of the blade instead of correcting one.
The solution is a flattening stone (also called a lapping stone), passed periodically over the surface of the sharpening stone to bring it back flat. There are two routes: a coarse stone dedicated to this job, or a diamond plate, of which the Atoma brand (made by the Japanese company Tsuboman) is considered the benchmark among enthusiasts. The advantage of a diamond plate is that, being mounted on a perfectly flat metal base, it never warps in turn, which means buying it once for the whole life of your stones. If you were to buy only one flattening tool, a medium-grit diamond plate (roughly 140 to 400) covers the vast majority of needs.
Stone or HORL3? The Question That Divides Enthusiasts
Do a bit of research on knife sharpening online and adverts for the HORL3 start flooding practically every page you visit for weeks afterwards: it is one of those products whose marketing budget seems to comfortably outstrip whatever went into development. Mentioning it in a series of posts about knives of this calibre borders on sacrilege, but I cover it anyway, for the sake of completeness, and dismiss it straight away for what it is: an entry-level tool for anyone who does not fancy taking on stones themselves.
The HORL3 (and its many imitators) is a German rolling knife sharpener that promises to solve the two most frustrating problems of freehand sharpening, holding a constant angle, and doing it in a reasonable time. It works via a magnetic support that locks the blade at a preset angle (15 degrees for Japanese knives, 20 for Western ones), while a roller fitted with interchangeable stone discs is drawn by hand along the edge. (Anyone unwilling to spend money on a commercial product can replicate the basic principle with a small DIY project: simply cut a wooden batten at a 15 degree angle and fix a magnet strong enough to hold the blade in place onto it. The result will not have the finish or the practicality of the HORL3’s interchangeable discs, but the underlying principle, a fixed angle guide plus an abrasive surface, is the same, and it is within reach of anyone with a saw, a magnet and half an hour to spare).
The limitation, though, lies precisely in its strength: the angle is preset, not matched to the specific geometry of your knife. For a mass-produced double-bevel Santoku or Gyuto, which typically already follows fairly standard angles, this is not a practical problem. For a handcrafted single-bevel yanagiba, whose asymmetric geometry was hand-calibrated by a Sakai craftsman specifically for that knife, forcing a generic angle is a compromise that risks betraying the very reason you bought a single-bevel knife in the first place.
My conclusion: a tool like the HORL3 makes sense, maybe, for the knife you use every day to chop onions, the double-bevel one, where consistency and speed matter more than technical purity. For a valuable single-bevel knife, the one you paid a significant sum for precisely because of its specific blade geometry, the traditional stone (or a professional, as discussed above) remains the more coherent choice, even if slower and more demanding to learn.
Buy Them in Japan, or Wait Until You Are Home?
Back to the question this post opened with, though a caveat is worth making straight away: the same reasoning does not apply in the same way to knives. Going in person to the districts covered in the earlier posts, Kappabashi, Tsukiji, Sakai, means having access to a depth of choice among blades, steels and craftsmen that is hard to replicate buying online from home: there, the experience itself, on top of the sheer range on offer, more than justifies the trip. For stones this holds much less true: the online selection, especially for synthetic stones, is nearly as wide as what you would find in a specialist Japanese shop. The reasons to buy them in Japan anyway come down, in my view, to two: wanting one as a souvenir with sentimental value, or deliberately speculating on the combination of a weak yen, tax-free shopping and no shipping costs, the reasoning I set out below.
In the Kappabashi piece I wrote that stones bought in Japan were “just unnecessary weight in your luggage”, and the logic behind that line still holds for a simple reason: synthetic stones from brands such as Naniwa, Suehiro or Shapton are global products, sold by specialist retailers across Europe and the United States to the exact same quality standard as their Japanese counterparts. Quality being equal, buying the identical Naniwa stone in Kappabashi or from a specialist website once you are home makes no difference to the product itself.
But there is a caveat here that I oversimplified in the original post: quality being equal, buying it in Japan right now can genuinely pay off financially, thanks to the combination of two factors already discussed elsewhere in this series, the yen’s exchange rate, which stayed weak for much of 2026, and the option to buy tax free by showing your passport (with the same warning about the system changing on 1 November 2026 already given for the knife and the cutting board). A Western specialist retailer, however reliable, adds an import margin, shipping costs and sometimes customs duties on top of what a Japanese customer would pay directly in store; buying locally, tax free, with a euro that buys more yen than usual, the final bill can come out lower even once you factor in that you have to carry it home yourself.
So the real question is not “is it worth buying in Japan”, but “is it worth it to me, with the suitcase I have, to carry it home to save a few dozen euros”. A medium-sized combination stone weighs roughly between 800 grams and 1.3 kilograms; a diamond flattening plate adds another 300 to 600 grams. If your suitcase already holds a knife and a hinoki cutting board, as described in the earlier posts, the weight really does start to add up, unless, as some people do, you set off for Japan with an empty suitcase specifically earmarked for shopping.
The picture changes completely for natural stones. Here the wider selection, the expertise to guide you towards the right stone for your specific knife, and the certainty of authenticity remain concentrated in specialist shops in Kyoto, even though many of these dealers now ship worldwide. If the goal is a genuine quality natural stone rather than simply a synthetic one with some geographic romance attached, buying it in person in Japan, ideally with the shopkeeper’s advice based on the knife you own, remains the more sensible option, regardless of the weight in your case.
In Short
If you own any double-bevel knife, for everyday use a mid-range synthetic stone (or a tool like the HORL3, if you prefer convenience to technical purity) bought wherever suits you, in Japan or at home, solves the problem without drama. If you own a valuable single-bevel knife like the yanagiba I wrote about, the sensible combination is: practice on something less precious, light maintenance done yourself, and a professional for the serious tune-ups, almost certainly in your own city once you are home, unless you are among the few readers who live in Japan or return often enough to rely on a shop like Kamata or the Sakai showroom mentioned above. And if you decide to buy a stone in Japan anyway, do it knowing that the financial saving, today, is real, but so is the weight in your suitcase.
