Hello and a few questions about knives and sharpening

Wow -- wonderful questions, and the knowhow to back it up. Welcome!

1. Yes, Japanese stones dish WAY faster than so-called oilstones. Synthetics generally dish faster than naturals, too. The aoto you were using may well have been synthetic, incidentally, although many natural aotos also dish fast. There are stones that dish very slowly indeed, but on the whole they're very expensive and not ideally suited to kitchen knives anyway (they're better for things like woodworking tools). The thing is, that dishing is due to mud, and the mud is what makes sharpening on waterstones so beautifully effective. If you've been rinsing that away, stop it right now -- sharpen in the mud. Let us know if you need advice on how to flatten a waterstone, by the way.

2. Sharpening past 2k -- depends on the knife, really. First of all, it's got to be pretty hard. Second, it's got to be pretty even-grained. Third, it's got to be something that actually wants to be hideously smooth. It's not a question of whether it hits bone or not: you can sharpen a butcher's cleaver to 10k without that really changing its effectiveness. But if you're going to shave sashimi slices so that the surface is like glass, the knife has to sort of slide between the molecules without any sawing, if you see what I mean. No knife you own, if I read your list correctly, will gain much of anything from it: not hard enough, not even-grained enough (which is one advantage of less hardness -- you don't need the finer and more expensive steels), and not designed for that kind of use anyway. The Global would take a bit more than 2k, I think, but I doubt you'd gain enough to make it worthwhile. And 5k+ stones can be remarkably expensive (and yes, they dish).

3. Buying a harder knife... that's, um, harder. It really depends more on the knife than just hardness alone. I mean, an idiot knife-maker could harden something to h*ll, but it'd just shatter when you used it much. That's not the point. Granted very fine-grained steel and excellent design, high hardness is an advantage, but that advantage does come at something of a price jump. And if you are considering such a jump, I would not go with the kind of knives you're contemplating here.

From where I stand, high hardness gains the cook a few things, and the very first is weight. You simply do not need to have so much metal holding up the edge when it's very hard. So for example, I still have a Wusthof 6" chef's knife, and I also have a 270mm (but actually measures 282mm) Masamoto chef's knife. The latter is thus closing in on double the length of the former. However, the Wusthof actually weighs more. Why? Fat blade. By Masamoto standards, a Global is kind of porky, and a Wusthof is frankly obese. And there are knives that are well into starvation-diet territory by comparison to the Masamoto.

Second, high hardness combined with good steel allows weird and creepy levels of sharpness. But if you're already regularly sharpening your knives to near-razor sharpness, it's just an improvement -- a big one, to be sure -- on very good, not some kind of quantum leap (by contrast to most folks who clunk along with dull knives and never know what remotely sharp is). The big thing is that you can sharpen the things much more acutely: if you've been doing, let's say, 20 degrees on a side, these things can easily take 13 or 14 degrees per side, which is a dramatic leap (40 total to 27 total).

Third, high hardness allows certain kinds of knife designs that are totally unsustainable without it, such as single-beveled knives, or grinding patterns like gross asymmetries. These things basically allow you to decrease your total angle even further: an usuba, to take the most extreme example I know, is normally built to have a total angle around 12 degrees, i.e. 12 degrees one side, 0 on the other. If you tried that with a Wusthof, it'd crumple like tinfoil.

Now do you want this kind of thing, honestly? It really depends how you cut, how much you want to spend, and so on. For most folks, this is a jump into the world of sharpness in the first place, but it isn't for you. So it's a different question.

Yes, these knives are more prone to chipping, but they're not delicate flowers or anything. If you're getting lots of chipping, either you're using the knife seriously wrong or you've got a mediocre knife. (I know: I have a very mediocre J-knife, and it's a nightmare.) I've never succeeded in chipping my Masamoto, and I sharpen it steep and very asymmetrical. Now that I use a very good usuba instead of the cheap POS I used to use, what chipping I get -- and it's not much -- is attributable 100% to my mediocre knife skills, and has been getting less and less common as I get better and better with the knife. So what does this mean for you?

Nobody can really answer that for you, of course. But I'd say that if you like to use knives with a fair bit of force, something that comes naturally with the sort of knives you've been using, you'd have to plan on a significant period of self-retraining. For example, if you use that fan-mince move that French chefs love, where you rock the knife rapidly back and forth around its tip while the heel moves side to side like a fan, mincing herbs or whatever, you're going to have to be very careful: you're going to need to use very little force downward on the tip end, or the blade will lodge slightly in the board and you'll get chipping from the sideways force of the rotation. If you're good with the knives you've got, and you like the style of cutting you do, and you're not looking forward to a bunch of retraining, then these knives may not be for you. You might want to think about going for a truly great example of the kind of knife you've already got, like for example some of the Sabatier au carbone lines, which would basically be like that indestructible thing you used to have only ludicrously wonderful.

If on the other hand you're not happy with your knives and cutting, you're ready to try something new, and you've got a little money to invest, you will probably love modern Japanese knives. Don't go halfsies: get the real thing. We can give all kinds of recommendations if you want to do this -- I won't jump the gun on that.

But it's really about where you stand now and where you want to go.

I would like to hear BDL s comments on your question. He is very Knowlegable re this topic/

Quote:

Originally Posted by Capsaicin 

Okay...  I would have to think about that, because at this point I have three chef's knives, and getting another one would pretty much take me into the collector category.

 

Man, I won't even mention how many I have then!

Hi,

Roughly speaking, it makes the stone active rather than passive, so it does more of the work for you. But there is some discussion lately, which I confess I do not at this point fully understand, about how hard stones are better for things like woodworking tools and soft stones for kitchen knives. I don't really see why this should be, but the people who are trying in their way to explain it lately do know what they're talking about. Maybe BDL or Phaedrus knows?

Well, that works, but it's not super-effective. You need to start with your stones already basically flat. It does generate both mud and flattening, but on the whole it is an inefficient method: you will wear your stones away faster than need be by this method. However, it is quick -- assuming the stones are already close to flat -- and very convenient. On the whole, I would prefer you think of this method as "dressing" the stone rather than flattening it: if you've got a 1k stone and a 6k stone soaking, you use the 1k to dress the 6k after you've finished 1k grinding; this does a little flattening and gets the mud going on the 6k. But if either stone is significantly dished you won't get very far this way.

This worries me, actually. The angles on that Global are thick indeed -- that knife could take thinner -- and when you move to both thinner angles and harder steels I worry that you will start to get chipping. You can certainly fix it with elbow grease, but it's irritating. I suppose what I'm saying is that you need to plan on getting some "microchipping," which is teeny-tiny little chips taken out right down at the edge, sometimes not even visible unless you're looking for them. That's easy enough to fix, but it does mean that for a few months, until you get used to the new knife or knives, you're going to be doing quite a lot of sharpening.

I always used to recommend that combo stone, but I don't any more because someone pointed out to me just how expensive it is. And since you've already got a 1k, what's the point? A King 1k is a wonderful stone for you at this stage of the game, if you ask me, because if you do run out and buy some J-knives, you're going to be doing a bunch of sharpening, and that's a reasonably quick stone, easy to use and flatten, and it's cheap and reliable. For 6k, I much prefer a muddier stone, like an Arashiyama or Takenoko, but I believe they're somewhat on the expensive side these days (I bought all my stuff in Japan, so I don't always have a clear sense what things cost elsewhere). As noted above, the 1k isn't really going to flatten the 6k, but it will do a decent job of dressing it to raise mud -- and that's important with soft, fine stones.

I hadn't really focused on the fact that you've been using a King 1k. I'm surprised that you find it dishes so rapidly. How often are you sharpening? And how much force are you putting into it? Having started on American-style "oil stones," you may have gotten into the habit of really bearing down. You don't need to do that with a halfway decent water stone. Admittedly things like Henckels and even Global are a b*tch to sharpen sometimes, but certainly if you buy a reasonably sharpen-able new knife you need to stop doing that -- and then your stones will wear slower, as well.

Good idea as far as the sharpening goes, but "the way these things cut" isn't all that generalizable. The main thing is that you can take such a knife to scary levels of sharpness, and they'll stay that way remarkably long. Still, a petty knife is a great place to start. Someone with more experience of a range of knives than I will have to give comments about the Tojiro and such.

Urgh, that's a long story. Some people hate it, some people love it. Here's the short version, as far as I know it -- and let's please not start a big debate about this unless someone wants to start a new thread.

The short version is that there isn't much difference, if any, between 15/0 and 7.5/7.5. The thing is, you can't actually grind a knife 7.5/7.5 -- it will crumble. If the steel is very fine and hard, an asymmetrical grind allows you to reduce your total angle; if the steel is coarse and/or soft, this really won't work. Basically what you're doing is trading crosswise stability for up-and-down stability, if that makes sense to you. To take an extreme example, a serious professional usuba is usually going to be ground at about 10-12 degrees on one side... and 0 on the other (though it is hollow-backed, which has other implications). If you had to make a knife that would hold up to cutting a carrot on a cutting board and was going to be ground 6/6, you would need some kind of ultra-super-duper NASA steel or something, and it'd cost a fortune; instead, you grind in this tricky way so that you get a lot of metal in line behind the edge and you never, ever apply crosswise force when cutting --- and a decent usuba isn't cheap, either.

So as I currently think about it, the question you're asking is in a sense precisely the wrong one. The question isn't the difference between 15/0 and 7.5/7.5, but the difference between 15/5 and 15/15, and the answer is fairly obvious. But watch out: serious asymmetry does make for a fragile edge and you have to behave yourself with it.

I love reading this board. You guys are awesome. Welcome to the forum, Cap!

If it's any consolation, my friends who actually study things Japanese for a living are pretty certain that the exchange will eventually re-balance --- but it will probably take a couple-three years.

I use a bastard file for flattening my oilstones. It works well and I don't use the file for anything else. You can also reprofile your stone with your fingers, like I did today - LOL . . .

Ow. Reminds me of when I was first starting sharpening, and I was trying to hold this perfect angle, and without realizing it I had a finger actually holding the angle by resting on the stone with the flat of the knife on top, sort of like one of those little gimmick things people sometimes clip to the spine of a knife, you know. Grind, back and forth, hello cleanly-polished finger! (It didn't help that the water I was using was seriously cold, and when my finger warmed up OWWWWW!)

The old bastard file in the garage works great for my stones - at least until you can get the actual correct tool.

HI Cap

Being still sort of a newbie myself I wanted to chime in as some of the things your going through I just did as well, and maybe I can help save you some frustration or confusion etc.

I have never used a Global so I can not compare or comment etc, but I did have similar Henckels and my recently purchased J knives include a Tojiro petty so I will stick with comparing on these.

First thing I learned real fast was that J knives sharpen very differently than Henckels, and also are obviously sharper OOTB. So much so that I can not even comment on how Henckels sharpen on whetstones because soon as I was able to handle and do a quick test on the first Tojiro I received I sold all my Henckels before the whetstones arrived. Sort wished I waited so I would have had the experience, but did get more than expected for my old ones due to the Christmas rush.

I can save you some time as I did not have too much luck going asymmetric with my 8" Henckels chef. It did improve it by making it a bit sharper (but that could have been due to more acute angle etc) and it would hold the edge slightly longer, but after spending some time with the Tojiro's and Fujiwara I have now all that was well sort of a joke in relation. Sure it would shave forearm hair, but not really any better than the Tojiro did OOTB and it would not hold the edge nearly as long.

I should note that before selling the Henckels I sharpened them one last time, but also reduced them to a more blunt angle so that the next owner would not be going crazy or cursing me because they would have to be constantly steeling them or worse.

I had used the Tojiro petty as somewhat of a test knife for sharpening (mostly so that I was not chancing messing up one of the larger more expensive ones, and it is shorter and a little easier to do) so I can say that it did not like my oil stone (I used only the softer washita side, but it was slow) but was a lot better on the 2K glass stone and 6k Arashiyama, and since being thinned a bit and sharpened a few times it is at a level of sharpness that my previous knives could only dream of. I know that is a pretty bold statement, but I believe it 100% and it is true.

A couple things to remember on the Tojiro petty is that the handle is not as large and bulky as what you have read as those comments are on the gyuto and the petty uses a smaller handle. I actually like it as it is still a bit boxy which gives a good grip (remember you only need a light grip due to the sharpness anyhow) and it is very comfortable for me, but also we have very different hands as mine are more boxy than long etc.

Since the price point on them is so low right now (under 30 if I remember right) and below what I paid for my previous ones on clearance I think you got a great idea to just pick one up and experiment. Just don't be surprised if you end up thinking if this is the low end of the J knife world WTF is the high end like, and that is exactly what I did myself. Either way you will be able to get a feel for what your getting into without a large outlay of cash and the fact that you have that 1k stone already is a big plus as well.

Oh and get those stones flat (I am guilty of not doing this on my oil stones for years, but it seems even more important on wetstones) as it seems when you get to sharpening at more acute angles the dish can mess with you as it does change the angle your sharpening at during the beginning mid and end of the stone and that makes it really hard to be holding a constant angle. This did not seem as obvious on the softer german steel at less acute angles but was real obvious when bringing them to be more acute.

Also I have found that even though this is an entry level knife I really am very happy with it, and have become a fan of VG10 real quick.

Good luck in whatever you decide!

Cap, look at the toolbar above where you type the message ^^^^^^ There us a "film strip" and just to the left is a little "insert image" icon. That is your photo loader - click on it and you'll know what to do.

Errr... I don't think that's a great idea, Cap. Soft steel. Asymmetrical works because of hard steel.

Do you know much about architecture and stuff like that? If you build a triangle, it turns out that you have to figure out which part of the triangle is most subject to stress. If it's on the narrow point (supposing something other than an equilateral), the best thing is to have the longest side in-line with the stress. With knives, this is remarkably difficult to achieve, so what you do is to make the second-longest side sustain maximal stress. But that depends on being able to ignore the cross-wise stress. That requires hard steel. A soft steel, e.g. a Wusthof, is basically made to collapse with cross-stress, and you bring it back into line with a honing rod. Asymmetrical grinding means that almost everything is just a hair crosswise at a peculiar angle (think of it like a chisel going down 5 degrees off straight and you'll see what I mean). Hard steels can ignore this; soft steels can't.

So in short, I suspect that if you grind your Wusthof that way, you'll just get the worst of all possible worlds -- a soft, collapsing edge that won't do the work.

Quote:

Originally Posted by ChrisLehrer 

Errr... I don't think that's a great idea, Cap. Soft steel. Asymmetrical works because of hard steel.

 

Do you know much about architecture and stuff like that? If you build a triangle, it turns out that you have to figure out which part of the triangle is most subject to stress. If it's on the narrow point (supposing something other than an equilateral), the best thing is to have the longest side in-line with the stress. With knives, this is remarkably difficult to achieve, so what you do is to make the second-longest side sustain maximal stress. But that depends on being able to ignore the cross-wise stress. That requires hard steel. A soft steel, e.g. a Wusthof, is basically made to collapse with cross-stress, and you bring it back into line with a honing rod. Asymmetrical grinding means that almost everything is just a hair crosswise at a peculiar angle (think of it like a chisel going down 5 degrees off straight and you'll see what I mean). Hard steels can ignore this; soft steels can't.

 

So in short, I suspect that if you grind your Wusthof that way, you'll just get the worst of all possible worlds -- a soft, collapsing edge that won't do the work.

Have to admit I did read that more than once as it is a bit involved, but I know it is true because I did have problems with the Henckels I did grind to asymmetrical etc.

I did use my least expensive knife at the time so that I would not worry much if I totally messed it up etc, but even though it did get sharper and oddly in opposition of what you describe above the edge oddly did not collapse as quickly as when it was 50/50 at the same angles. Keep in mind I did grind to angles that it would not support with either edge shape, and did add a second or micro bevel before selling it to calm things down a bit for the next owner too.

Maybe the best idea and what will be of most value to cap is about using a less expensive least liked knife to experiment with, and that the Wustof he has may be better to keep more inline with the oem profile or close to it as this knife sounds like it may very well end up being his heavy duty bone breaker etc.

I think you guys have figured out by my questions in other threads I am far from the authority on this stuff, but I am pretty confident in the idea of messing with your knives you have the least interest in before changing the ones you like.

Also I am glad I did mess around with different angles and asymmetry as it was a good learning experience and believe it would be the same for cap as well (or anyone else looking to improve their skills and knowledge).

Quote:

Originally Posted by Capsaicin 

 

Just to summarize what I've learned though -- the asymmetrical thing only works on very hard steels because it relies on the steel not bending from side to side?  So this wouldn't work for my Globals either?

Looks good - you kept the grind pretty even along the edge - Yah, not really going to gain much by doing it on a german knife, but nobody will take your birthday away for doing it. Fun is Fun :D

The asym profile really only works on thin - and - hard blades. the Wusthof is thick and soft and also curved. Your Wusthof is really designed to put heavy-duty amount of steel behind a bi-lateral edge, for even cutting under pressure. With an asym angle, you may find the knife wants to twist toward the acute-edge side when bearing down on some carrots or something, because of the width of the blade behind the edge. This isn't as much of an issue with a very thin 70/30 edge because there is no large back-bevel/wedge of steel forcing its way into the product after the initial cut is made.

If yoi were really motivated, and this has become a test/play knife anyway - you could try thinning the whole of the blade - take a half-millimeter off of each side of that beast, at least along the spine-side. Then you will have more of a flat blade instead of a huge wedge-shaped blade.

The cool thing about old knives, especially German chef's knifes, is that you can always continue to widdle it down to a utility knife, a cheese knife, an oyster knife, lol...  have fun with it.

I've used this 8" Wusthof for years with a 15/15 bevel and it works fine. German steel is "soft" but the J-knife crowd makes it sound like the steel is made from butter and bacon fat. The edge on an 8" Wusthof will hold up just fine with this angle, because there is so much steel backing the edge.... I wouldn't try anything less than 15 degrees but it will do just fine at that angle - in a commercial environment or at home...

Cap, it has more to do with how damn wide the knife is . . . If it goes to such a tiny point from a huge wedge - It will "split" things in half, not really cut them in half.

I would say a Wusthof knife could take a 10-degree angle IF it was only used on and never left the comfort of your butcher block. The edge would ravel on the first peppercorn or bone you hit however.

It will be fun to play with, sure, I just used 15/15 because that is what I have on ALL of my double-bevel knives. (I have a Global paring knife that's a 10/10 however)

And the 15/15 angle, for the width of the blade, all works together and makes sense, and is durable.

It is the fact I also keep a 15/15 on my J-knives that would be more of a reason to banish me from the knife forums... for a German knife - hell, do-it-up, man...  : )
 

Quote:

Originally Posted by Capsaicin 

The question is of course, if 15/15 (30 total) works just fine, would it take 12/12 (24 total)?  And if that works, would it take 10/10 (20 total)?

 

I think I will play around by using the knife normally, and pushing it a tiny little bit each time it actually gets dull and I actually do a full resharpening, until I start running into problems.  If I notice a significant change in the time period between required resharpening or an actual collapse in the blade, I'll just grind he whole thing back to the previous angle.

Most German knives won't go much more acute than a 20* angle without the edge collapsing.  That is, it bends out of true and requires steeling to straighten it.  In my experience, 15* is far more trouble than it's worth.  This is a function of the interaction of the materials properties, "strength" and "toughness."  We sort of shortcut the discussion by using Rockwell "C" hardness as a metaphor -- but remember that although hardness is helpful it's only a metaphor and is inexact; and that furthermore "C" hardness (indentation hardness) is the least relevant type.  The collapse will occur cutting onions and parsley on the board -- you don't need any special abuse.  In fact, that's almost definitional in the idea of "too acute," as any edge will roll or chip when it's abused. 

Anyway, the Germans tend to be relatively soft and you're better off sharpening relatively obtuse, durable and abuse resistant angle.  And if durability and abuse resistance aren't  that isn't the greatest part of their charm, I don't know what is.

If you want to max the performance on a Wustie, Henckels, or Lamson, you can thin the blade to 15* and sharpen a 20* double bevel on top of that.  It's not easy to do freehand -- but that doesn't mean it isn't doable.  It's somewhat easier if you just "micro-bevel" the primary.  Since you're going to be using a steel relatively frequently, it doesn't pay to put too much polish on the knife.  Even the finest steel will create some scuff.

No matter how sharp or acute you get a German, you'll never get it to perform at the same "fall though" level you can with a Japanese made knife or a French carbon.  As Trooper said, the German style, stainless blades are just too thick.   But... Let's get one thing straight.  There's nothing wrong with a 20* edge.  It's plenty sharp to cut brunoise and portion fish.  Billions of great meals have been prepared with them so hold on to your sense of perspective and remember where the real bottom line lies. 

Finally:  You can NOT sharpen more acutely bit by bit.  It's all or nothing.  On the other hand, you can go the other way incrementally.  If you need me to explain the geometry for you, I'll be happy to do so; but I'm betting you can think it through relatively easily yourself and that doing so will help the way you think about sharpening geometries in general far better than others' explanations.

BDL