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Speaking of weird knife phenomena...

I work part-time for a kitchen store...I had someone bring back FOUR Shun knives yesterday: 3 from the Classic line and one from the Elite line...

ALL four of them had the same problem....pieces of blade missing all along the edge. I guess like big chips from tip to heel?

In my first life I was a housewares buyer for two major retailers, in my second life I cooked professionally, now in my third life I'm doing this. I've seen a lot of knives and a lot of knife issues in these different jobs...but never anything like this.

I was actually speechless when they were shown to me. I asked if they'd been doing a lot of sharpening thinking maybe the edges had gotten really brittle and unstable and were crumbling from that"no, we never do anythign to them" Asked if they were using them on bone. Asked what kind of surface they were using(bamboo was the answer). Asked if they were going through the dishwasher...how they were storing them.

I was given all the "right" answers of course...but clearly there was something going on with how these knives were being used to cause this...there's no way we sold four separate defective knives into one house(from two different lines no less)...and if there were production issues we'd be seeing it in our store and other locations...

What in the world causes this? I know it was something being done to them and would like to know for future reference....

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  1. odd....I've been a Wusthoff man for years and my aunt bought a Shun recently...I gave it a test run and am not convinced it is gods gift to cutlery...my Wusthoff feels SO MUCH MORE well built....could just be not so great quality control...

    1. LOL ... I have done this (it gets worse, it was at a friend's house, it was her brand new cleaver-style Shun knife). We were doing a "deconstructed" turkey for Thanksgiving per the instructions in the Julia Child / Jacques Pepin Cooking at Home (a wonderful book and recipe), Julia says to use a cleaver and a hammer to take the ends off the leg bones. Noted in book: next time use axe and hammer.

      1 Reply
      1. re: firecooked

        You do realize that the Shun cleaver is not a meat or bone cleaver, right? It's a vegetable cleaver.

      2. I might have had the same issue with my Shun knives. They have both turned almost serrated over the past couple of years with an even 'chipping' effect running along the blade. I sharpen them frequently using a spyderco sharpener and stored them in a wooden rack. I also happened to be living on a boat in the tropics for 2 years and so I had just chalked it up to another victim of extreme corrosion.

        However, a friend of mine who is fanatical about old knives and swords said that he thought it was due to the damascus-type steel and the way it wore naturally. He said that the layers of steel tended to wear or corrode at different rates and that you are left with an even (or mostly even) 'serrated' effect.

        I have not been able to find much information on this though and when I mentioned it to a local high-end knife shop where I thought about bringing the knives to be re-edged professionally, he said I had probably been chopping rocks with the knives or something, that he had never heard of such a thing happening. I haven't had them 'professionally' sharpened yet needless to say.

        I got over it basically and continue to use them daily, sharpening as usual on my own and they work great as always I think. Here's a link to what the edges look like: http://sv-timemachine.net/?p=308 (the close-ups of the knife edges are at the bottom of the post).

        6 Replies
        1. re: TimeMachine

          Interesting TImeMachine....the knives that were returned to us had much bigger chips than yours! Like little holes had been punched all along the edge of the knife...maybe a few millimeters big. We live in the desert so not humidity. Bummer though that you're experience that kind of knicking and chipping. Have you contacted Shun at all about the problem?(of course might be hard if you're still out traveling!) One of the way too many knives we have in our house is a Shun and we've been pleased with it.

          I'm sure the ones I took back were abused somehow...even if Shun has quality issues we'd see more of these coming back with this problem and like I said in nearly 20 years of some sort of professional experience with knives and knife manufacturers this is the first time I've seen anythign that looked like this. Customers wouldn't own up to doing anything odd with them so I'm really at a loss...and curious. I should take some pictures of them before we send them back to Shun...I'll do that this week.

          Customers mentioned they had had Henckels for a long tiem so I guided them abck to those, I was afraid to let them walk out with more Shuns without identifying the problem...figured we'd just end up with another expensive return...

          1. re: ziggylu

            Hmm. I hadn't thought of contacting Shun (I'm back in the US now). My plan was only to 'fix' the edges by just having them professionally ground/resharpened but the local knife stop guy turned me off. This seems silly perhaps but I would not want to trade my 'old' knives in for new ones even if they were identical, if that makes sense. Sentimental I guess. Plus, they still hold a great edge and sharpen nicely--essentially they are as good as new, minus the cosmetic issue.. I suppose I could email Shun to see if they had ever seen or gotten any returns with similar issues to my knives and had any suggestions. I also fear that I'll be 'accused' (well, that's putting it strongly) of mistreating them when I'm more neurotic about taking care of them than most people I know. Well, discounting the whole tropical boat experience :)

            1. re: TimeMachine

              TimeMachine -- unfortunately I believe your friend in wrong, as much as he knows about knives! The Shun are constructed from layers, not folded steel, the middle layer being the core steel that does all of the cutting, thus there is not damascus pattern and no folds or differential spots within the metal to be softer or harder, etc., leading to chips.

              This happened to my Shun 8" chefs, I returned it and bought a gyuto and haven't looked back! I've heard rumors that because of the scale the Shun operates at, they are not tempering their steel correctly, thus the metal crystals are very large and more prone to chipping. I'm no metal expert, but it makes sense, given my limited knowledge and that I heard from a knife maker!

              1. re: mateo21

                I think you are right. Upon inspection, the damascus-looking part of the blade is only in the outer layer of the metal; the inner core (which is tapered into the cutting edge) does not have the striations.

                I still haven't sent them back though I've been told that Shun will resharpen for free (minus postage).

            2. re: ziggylu

              Ziggylu, we are in the same business.I have not seen any Shuns come back with those issues. This is the first I have ever heard of something like that. From what you say it sounds like those knives were abused. We do sharpen knives and I have seen some beat up knives be given new lives. Henckels are not the knives they used to be, I have seen one of them come back broken with most of the blade missing. We just sell Wustof, Shun, Kyocera, and Forshner any more. I have Henckels from years ago and those are great knives.

            3. re: TimeMachine

              If you can ever make it to this:
              http://www.metalmuseum.org/repairdays...
              you should be able to get definitive answer. Some of the most experienced metal smiths in the country travel to help with this fund raiser. It is a great opportunity for them (they get to see amazing once in a lifetime pieces come through) and for the owner (a chance to learn the history & how the piece was made). Ranges from goldsmiths, blade makers & blacksmiths.

            4. they probably cut stuff up that they shouldnt have and didnt mention it to you.

              all the knives probably went through whatever they tried to cut too, if it happened to all of em.

              These japanese blades are harder and thus chip easier.

              My japanese santoku will only be cutting veggies and some meats. I'll use my wusthof for the stuff with bones etc.

              1. Frank's right - it's not the damascus (which is a folded steel finish) but that these knives are bifurcated - they're made from 2 different steels, and the inner steel (with the edge) is very hard and very thin, and susceptible to chipping. The damascus is the way the cladding metal is finished - it is typically a softer metal. The idea is that a blade that is made strictly from the hard metal would break too easily - so you fold, forge and weld the outer, softer metal onto the inner harder metal to give it some ability to bend without breaking.

                Chipping can be from poor manufacture - but unless a bad batch slipped through the Shun factory, I doubt that this is the case. Bad tempering and over-heating can cause the metal to form a large grain structure which is very brittle. It may be worth contacting your Shun distributor to see if there has been a report of a bad batch.

                It's far more likely that this is from aggressive misuse. Cutting bones, cutting on hard surfaces (glass cutting boards or ceramic dishes) and dropping knives onto hard surfaces can all chip these knives. Washing in dish washers can harm good knives as well.

                I've always said that people who want to invest in good knives need to learn how to maintain them. You don't treat your Porsche like a Chevy, or your Rolex like a $15.95 Timex. If you're not willing to put in the time and effort, stay with the Solingen steel, (Wustoff, Henckels, Forschner/Victorinox) or the 440A steel on your Cutco.

                PS - bamboo is extremely hard stuff - that could be the problem.

                1 Reply
                1. re: applehome

                  It's common to see people use a twisting motion when cutting hard vegetables. This torquing of the blade can casue chips

                2. We had a slow day today and had a chance to take these out and look at them again.

                  Definitely had to be abuse of some sort...again they were sold separately and from two different lines...so even a bad batch from Shun woudln't make sense.

                  we tried banging them around a little to see if we could create the same thing...on cutting boards, stacks of paper, etc we couldn't. The steel didn't damage them. But we did find if we banged them together we could make them chip more. So....somehow they were getting used on something pretty hard and/or metal. Our banging on bamboo didn't seem to cause damage but who knows how they were being used and maybe that was part of the problem(personally i'm not a fan of bamboo boards because of the hardness anyhow...)

                  Strange...there's no telling what they might have been doing with them actually but we had fun coming up with some crazy ideas! LOL

                  37 Replies
                    1. re: scubadoo97

                      if they were old enough to have careless kids... maybe that's exactly what happened. the kids decided to play with them? But, that's probably not it -- because they would have come to the store complaining that the store sold them knives that could have hurt their children...

                    2. re: ziggylu

                      Sounds like somebody tossed those knives into a drawer that was opened/closed very frequently where they bashed around with all of the other knives (or worse, stainless steel cutlery).

                      1. re: ziggylu

                        I've had my Ken Onion Santoku replaced with the Kaji Santoku a couple months ago after 10 months usage, and the problem of blade chipping remains. I didn't abuse them, and I've read after the first incident that this happens to other Shun users. I think today I'll be returning it to get it replaced with a Global knife since TimeMachine's picture shows that it's hold for him. I love the Shun's sharpness and handle but can't live with the fact that metal pieces are chipping. Have we ingested without knowing it?

                        1. re: cookinginco

                          "the problem of blade chipping remains"

                          Which one? Ken Onion or Kaji? Or both? I am surprised if both chip badly.

                          "I didn't abuse them"

                          There is abuse and there is abuse. I am sure you didn't toss the knives into the sink that kind of abuse. Usually, the microchipping goes around after the first round of knife sharpening. On the other hand, many abuse their knives without knowing it. If a person is used to German knives, he/she may have picked up a lot of bad habits over the years.

                          "replaced with a Global knife "

                          The Global knives are made of softer steel, so they should be more resistance to chipping.

                          1. re: Chemicalkinetics

                            I mainly use my Kaji knife for chopping vegetables and boneless meat. I use my Henckle cleaver for chopping up any meat with bones in them. So, the chipping problem remains for me in this line of knife- Shun, both the Shun Ken Onion and Shun Kaji. BTW, Williams Sonoma is great with exchanges. It's interesting that ziggylu mentioned that the unbought knifes in her store were chipping and that they had to send them back to Shun.

                            1. re: cookinginco

                              The VG10 of the Shun Ken Onion is known for being a little bit chippy (though many users never experience a problem). The SG2 steel of a Shun Kaji - less so, though of course all harder steel knives will chip in some situations. So if both of your knives have shown the same types of edge issues when you've used em, I suspect you have another problem. Also, I can assure you these knives aren't necessarily too thin for an everyday kitchen knife, as you assert below - I use some knives that are much thinner and about equally chip-prone as Shun's VG10 offerings without any chipping problems.

                              I'm not trying to accuse you of anything BTW. I'm sure you didn't cut through bones or cut frozen-solid foods or leave the knives banging around in a drawer or dishwasher. That leaves less obvious problems. So, a few questions:

                              1) What do the chips look like? Are we talking about many tiny chips that you could maybe fit a grain of sand into? Or bigger chips you could see from maybe 5-10 feet away? Are they all along the knife edge or concentrated in one section (tip, heel, middle)?

                              2) How and how often do you sharpen? Do you use a steel in between sharpenings? How long after sharpenings do chips typically appear?

                              3) What type of cutting board do you use?

                              4) How do you cut most things - do you use a rocking motion? Chopping? Do you cut fast or slow?

                              We might still be able to salvage your relationship with your Shun. Just as important - you also could run into some problems with a Global, depending on what your issue is.

                              1. re: cowboyardee

                                "So, a few questions:"

                                I'd also add:

                                2b) what type of steel (if any) or ceramic do you use?

                                and:

                                5) After which operations (type of use) do you notice the chips appearing?

                                1. re: Eiron

                                  "I'd also add:

                                  2b) what type of steel (if any) or ceramic do you use?"
                                  ____
                                  Good catch. I didn't realize I had left that question out.

                                  1. re: cowboyardee

                                    I'd also add
                                    "do you cut bread with it/them"

                                2. re: cowboyardee

                                  1) Kaji- chips more like nicks
                                  Ken Onion- Chips were bigger
                                  Both chips located in middle of blade.
                                  2) I don't sharpen.
                                  3) I use mostly soft plastic, sometimes wooden board.
                                  4) I use both rocking and chopping. With the Rachel Ray santoku, I chop/rock much faster. With these knives, it's much slower because it's sharper and more delicate.

                                  Question, should I get my knife sharpened with a rolling stone done by a local professional ($2/knife) or should I send it back to Shun for sharpening?

                                  Many thanks!

                                  1. re: cookinginco

                                    Glad you're still around, Cookinginco. If you haven't gotten rid of your Kaji yet, there may still be some hope for you and that knife. If you have, just apply what I'm about to say to any future experiences you have with Japanese knives - Globals, for instance, will behave in a similar way to the Shun Kaji with respect to chipping, though to a slightly lesser degree.

                                    I'm starting to get an idea of what's going on. For starters, chips centralized in the middle of the blade (usually just a bit more toward the tip than the heel) are very typical of damage done during rock chopping, since that's the pivot point of the knife. A plastic cutting board can accentuate this problem, as can rock chopping really fast (you don't) or with any significant downward pressure while you cut.

                                    Additionally, some harder steel knives are known for having extra chippy factory edges - the problem sometimes goes away after the first sharpening or two.

                                    Beyond that, if the chips are small enough - just a little jagged roughness in the edge, only visible if looking closely - it might be best not to even think of it as chipping. It might be best to think of it as just how hard steel knives go dull. You probably know that over time the edges of softer Western knives fold over and mash down until they're not sharp. Harder Japanese knives do this to a lesser extent - they also go dull is by losing tiny little chunks of the edge. I understand health concerns ("what if these bits got into my food?") but remember a few things - a) these metal shards are very, very small b) Japanese people have been using Japanese knives for a long time with no ill effects. You said you got this knife a couple months ago. That's a bit quick for these knives to go very dull, but rock chopping could definitely account for that - the chipping could just be nothing more than your knife showing its wear. (If you're still not sure, if you post a closeup photo of the edge, I could tell you more accurately).

                                    So, what to do? Definitely get it sharpened. I'm not sure what to tell you with respect to Shun's free service - I've heard they are no longer offering it, but I don't know if that's just for newly sold knives, or if it has gone into effect already. Normally, I'm pretty particular about who and how to sharpen a nice Japanese knife, but in this case, I think your local guy using a rolling stone wheel should be fine. Just ask him and make sure this isn't the first thin, hard Japanese knife he's sharpened. The important thing is to remove that factory edge and leave you with an unchipped cutting edge. If you have more questions about sharpening later, we can definitely help you here.

                                    For the future, work on cutting technique. For one, push cutting accomplishes the same thing as rock chopping, but is far easier on the edge of a Japanese knife. Here's a video with some (slightly awkward) push cutting. Skip to 0:45
                                    http://www.youtube.com/watch?v=Ni_mSc...
                                    If rock chopping is too ingrained for you to give it up, you can work on keeping lateral movement to a minimum and using no more pressure than you need while doing it. Clean, smooth strokes. You can go fast eventually, but you should have good technique before you do so.
                                    Also as for cutting boards, with respect to knife edges, end grain wood > regular wood > plastic (~ = bamboo and rubber >>>>>>>>>>> glass and ceramics). Using the wood board for the Kaji will help. An end grain board will help even more.

                                    Sorry for the length of this reply.

                                    1. re: cowboyardee

                                      Here are the pictures! I have a feeling they will grow larger as time goes by.

                                       
                                       
                                      1. re: cookinginco

                                        Thanks for the pics. Those probably will not get bigger with time. Rather, with time you'll see more of em. That type of chipping is easily removed with a simple sharpening.

                                        You can minimize the occurrence of such chips with some of the pointers I mentioned above, and as I said, you might not see em again after the first sharpening if you're careful. But unless they are happening very regularly - say your edge is really torn up with them after just a couple months of home use - I wouldn't take that type of chip as a sign of a defective knife or a major problem. It's nowhere near as severe a problem as seeing bigger chips like the one below.

                                         
                                        1. re: cowboyardee

                                          Thanks for all your suggestions. I think I will get an end grain chopping board. Just one more thing, when I watched the Youtube clip on how to chop that onion, did you notice he used the rock motion to finish chopping the onion? As I was making dinner last night, I noticed that in order to mince garlic, the only way to do that is to use the rock motion. Besides, isn't the santoku knife designed for that type of cutting?

                                          1. re: cookinginco

                                            " I noticed that in order to mince garlic, the only way to do that is to use the rock motion."

                                            I won't say the only way to mince garlic is to rock chop. Otherwise, more than half of the world will have problem mincing garlic.

                                            "Besides, isn't the santoku knife designed for that type of cutting?"

                                            Santoku knives are definitely not designed for rock chopping. The European Chef knives are. This does not mean a Santoku cannot be used for rock chopping, but it is not "designed" for it. It is a "push-cutting knife" when compared to an European Chef knife.

                                            Like cowboy said, these are minor chips. A knife sharpening will remove them. Harder steel knives require a certain refinement to handle them. Knife abuses are not only about knife storage and cleaning. More importantly, it is about how to use a knife -- knife skill. I won't say rock chopping is always abusing a Japanese hard steel knife. What I will say (and many have agreed) is that most people who use the rock-chopping motion do so in a way which is abusive to the knives. The truth is that certain motions are abusive to all knives, but German knives like Henckels and Wusthof knives are more forgiving. This is why many people who have used European Chef knives for extensive period of time may have picked up bad habits without knowing.

                                            1. re: Chemicalkinetics

                                              "Santoku knives are definitely not designed for rock chopping. The European Chef knives are. This does not mean a Santoku cannot be used for rock chopping, but it is not 'designed' for it. It is a 'push-cutting knife' when compared to an European Chef knife."

                                              Normally, absolutely yes. (Chem, you're slipping!)
                                              However, cookinginco has the Shun santoku, which means a Euro edge curvature rather than the typical flatter Japanese cutting edge.

                                              Not that having a curved edge automatically means you're safe rocking it. But in this case, I think cinco can be excused for thinking the knife was designed for this motion.

                                              1. re: Eiron

                                                "Normally, absolutely yes. (Chem, you're slipping!)"

                                                Age -- this is what happens to a person when he gets older. Take a closer look because this will (is) happen to you.

                                                1. re: Chemicalkinetics

                                                  "Age -- this is what happens to a person when he gets older. Take a closer look because this will (is) happen to you."

                                                  LOL, hey, I just "officially" got grouped with The Old Farts at a dinner Monday night. I don't know if that's better than having to sit at The Kids' Table, or not!

                                            2. re: cookinginco

                                              I mince garlic the way I dice an onion. Horizontal cuts then lots of thin vertical cuts then cut against the verticals to mince. I'd rather not use a gyuto but a paring or petty will work very well. No rock chop and no smashing.

                                              1. re: cookinginco

                                                Just to be clear, I'm not saying rock chopping is always bad. Just that doing it with Japanese knives requires cleaner technique than you're likely to have if you've never made a concerted effort to work on it.

                                                Push cutting can be substituted with no loss of efficiency in 95% of cases. For mincing garlic very fine, I prefer to neither push nor rock - that type of quick, drastic pivoting while rock chopping is especially hard on a Japanese knife edge. Rather I chop straight up and down very quickly, using my off hand hovering over the spine of the knife as a backboard for it to bounce off of to increase speed. Though the impact from quick up-and-down chopping looks violent, its actually easier on the edge.

                                                If that feels too awkward or unnatural to you, you can also mince garlic pretty fine using pretty much the same trick you'd use on onions: make a lot of fine slices lengthwise leaving the end intact, then a few through the width also leaving the end intact, then cut crosswise and you've got a fine mince. Not quite as quick, but it works.

                                                Finally, don't put too much stock in any one video. That was just the first one I could find that had a push cut I could show you. Ever since Salty took his videos off youtube, it's been really hard to find demonstrations of good gyuto or santoku cutting technique.

                                              2. re: cowboyardee

                                                Nice chip! Judging from the picture, maybe you shouldn't be cutting on the sidewalk?

                                                1. re: Eiron

                                                  "Nice chip! Judging from the picture, maybe you shouldn't be cutting on the sidewalk?"
                                                  ____
                                                  When I'm using my fine kitchen cutlery to dice rocks, where else would you suggest that I cut them?

                                                  1. re: cowboyardee

                                                    "When I'm using my fine kitchen cutlery to dice rocks, where else would you suggest that I cut them?"

                                                    Yikes! What's the HRC on that thing?!

                                                    1. re: Eiron

                                                      It's a Sabatier which means: who knows?

                                                      Actually, I just pulled that picture off the web. So if anyone ever compiles my posts into a book, they might not want to use that image.

                                                    2. re: cowboyardee

                                                      >>"When I'm using my fine kitchen cutlery to dice rocks..."<<

                                                      Lends a whole new meaning to "rock chopping," don't it?

                                        2. re: cookinginco

                                          Thanks for filling me in. It is unfortunately that both lines of Shun knives have not worked out for you thus far. You may have a bit better luck with Global knives because they are softer. On the other hand, Global are thinner even than Shun, so...

                                          Have you used a Japanese/Japanese-influenced knife before the Shun knives? Japanese knives are, in general, higher performance, but they do require more care, not just how to store and wash them, but more importantly how to use them.

                                          Cowboyardee has made some good comments. For example, you should not need to "steel" or "hone" your Shun knives with a honing steel. It is a bad idea in my opinion. Rock chopping can be more damaging for these knives than push-cutting or slicing. Many people who are used to German knives also picked up bad knife habits without knowing them. For example, moving the knife across a cutting board can be damaging for the knives. Many people don't realize it, but they drag the knife blade sideway on the cutting board from one cut to another cut. Hope you have better experience with the Global knives.

                                          1. re: Chemicalkinetics

                                            "Many people don't realize it, but they drag the knife blade sideway on the cutting board from one cut to another cut."

                                            Also, twisting the knife during rock-chopping is a common movement. This motion can easily pop chips out of a hard steel blade.

                                            1. re: Eiron

                                              "Also, twisting the knife during rock-chopping is a common movement. This motion can easily pop chips out of a hard steel blade."

                                              Yeah, I think that is probably a bigger factor.

                                              Twisting a knife during rock chopping or dragging a knife sideway motion during rock chipping are all bad habits for any knives, but they are particularly bad for hard steel knives like many Japanese knives.

                                              1. re: Eiron

                                                "Also, twisting the knife during rock-chopping is a common movement. This motion can easily pop chips out of a hard steel blade."
                                                ________
                                                Exactly. There was some confusion about this point earlier (time-wise) in the thread. Rock chopping - especially if done hastily, sloppily, and with a firm pressure - can get the edge of a knife imperceptibly embedded in a cutting board, and then that twisting motion applies lateral pressure to the steel. This type of pressure will chip out a hard steel very easily.

                                                For anyone interested, take a look at this video. Skip to 5:15.
                                                http://www.youtube.com/watch?v=dU3ALY...
                                                You can see how easily a knife chips when lateral pressure is applied. No impact or hard materials necessary. And those are pretty big chips.

                                                Cutting technique has a lot more to do with knife performance and edge retention than most people give it credit for.

                                                1. re: cowboyardee

                                                  "Cutting technique has a lot more to do with knife performance and edge retention than most people give it credit for."

                                                  Agree. A lot of people think of "knife abuse" as in throwing knives in the sink or using the knives to open postal packages. While those are knife abuses, they are obvious ones. How a person use a knife to cut foods has significant impact on the knife ede.

                                                  1. re: cowboyardee

                                                    Wow, that's surprising to me that he could do that with a plastic lighter! (Nice 10-sec close-up on those fingers (starting at 5:42) by the way!) I don't have sound; does he say what the steel & hardness are?

                                                    1. re: Eiron

                                                      "I don't have sound; does he say what the steel & hardness are?"
                                                      _______
                                                      Not that I caught.

                                                      I could take an educated guess though - that;s probably a knife that he made. And he only works with a few steels usually (hitachi white #1, white #2, blue super/AS, and - rarely - 52100/SUJ2). From the patina near the edge visible at 6:20, I'd guess that was blue super, which he tempers on other knives to ~ HRC 62.5 - fairly typical for AS steel.

                                                    2. re: cowboyardee

                                                      "Cutting technique has a lot more to do with knife performance and edge retention than most people give it credit for."

                                                      Agreed.

                                                      I just sharpened my Kanetsune 210mm gyuto (3rd time in 15 mos) & Shun 150mm petty/utility (2nd time in 15 mos) yesterday. Neither one had chips.

                                                      But, I only cut on wood boards, only hand sharpen on water stones (& recently started stropping on wood-backed leather), never hone these VG-10 knives, & pay attention to my cutting motions.

                                                      Now, when I sharpened the 2nd Kanetsune a few months ago (after I sold it to a co-worker & he brought it back to me for sharpening), I noticed two or three micro-chips & a "micro-pit" in the blade edge under magnification. They only became visible after polishing & stropping (showing up against the bright mirror edge). I'm still waiting for him to bring it back so that I can see if there are more chips/pits BEFORE sharpening this time.

                                                      1. re: Eiron

                                                        "Now, when I sharpened the 2nd Kanetsune a few months ago (after I sold it to a co-worker & he brought it back to me for sharpening), "

                                                        So you sold your knife with "free knife sharpening service" offer?

                                                      2. re: cowboyardee

                                                        Just got a chance to watch that youtube video. Nice. So Murray Carter is teaching us how to distinguish a stupid knife maker from an idiotic knife user? Does the knife chip because the knife is badly made? Or does the knife chip because the user does not know how to properly use a knife. :P

                                                      3. re: Eiron

                                                        Both you and Chemicalkinetics make good points. With harder Japanese steel you should adopt different techniques. I try to avoid rock chopping, sliding my edges sideways on the board, twisting the blade and cutting into hard items like bone or frozen foods. I will pull out my German Chef's knife or cleaver for cutting those hard items. I don't mind folding the edge but don't want to get big chips in my edges. I will ultimately get a few small micro chips under normal use but they sharpen out quickly.

                                            2. Interesting to see this thread because jackp's nephew is a chef. One of the newbies in his kitchen was going to throw away a Shun with exactly this problem. The nephew took it and put a new edge on it and is quite happy with it.

                                              The knife-loving jackp agrees that it sounds as if the knives were used to cut bone and the issue is the two different steels used. Maybe the customer needs a good cleaver. Many people think that just because a knife is a good knife, it can be used for anything.

                                              1. I myself am not a big fan of Damascus steel, I think it is highly overrated. I collect j.a. Henckels and globals and never had a problem with breakage on the edge or otherwise. When it is time for professional sharpening I have had great experiences with sending them out to be sharpened by Ambrosi Cutlery. These guys really have a magical touch, finally a professional grinding service that actually kept the proper shape of the kinfe along with a strong edge. I hope this provides an inexpensive yet efficient way to restore your edges. (Ambrosicutlery.com)

                                                8 Replies
                                                1. re: joeychef

                                                  FYI everyone - the Shun is not a true Damascus steel....they use a Damascus 'look'
                                                  Damascus steel blades are $$$

                                                  1. re: jbyoga

                                                    Damascus is a technique for finishing the forging that typically uses two different types of steel and leaves end-grain patterns on the side of the knife. While it represents some extra work for the forger it has little to do with the real quality and it most certainly isn't a specific "type" of knife - a damascus finish can be put on any thickness and virtually any type of steel.

                                                    The type of steel (or types in a bifurcated knife) is the most important factor, along with the tempering and finishing used. Whether it is forged or stamped has a bearing. Japanese developed their techniques quite differently from western steel, so the basic shapes, forms and to some extent, materials are different. But even within Japanese knives of today, many are some level of compromise between a true Japanese style and western styles - these include the Globals and the Shuns. Some Japanese blades are single-sided, but many are double-sided. For real Japanese style blades, see the sites below.

                                                    Japanese blades need to be hand-sharpened - don't spend $200+ on a good Japanese blade and then take it to your local skate sharpener with his magna-grinder and his $2.00 super-fast service.

                                                    Here are some on-line sources for more info, knives, and sharpening services:

                                                    good sharpening dvd - great knife selection
                                                    http://www.korin.com/knife.php?PHPSES...

                                                    http://japanesechefsknife.com/KDSerie...

                                                    hand-sharpening service (site also sells):
                                                    http://www.epicedge.com/shopcontent.a...

                                                    ag russell's steel guide - (site also sells their own kitchen knives):
                                                    http://www.agrussell.com/knife_inform...

                                                    great knives, wonderful sharpening dvd'd - master bladesmith:
                                                    http://www.cartercutlery.com/

                                                    1. re: applehome

                                                      When I was looking into this stuff, I found that the 'damascus look' knives are often sold as damascan steel, and it's not true. Damascan steel was developed in Damascus (or thereabouts) many years ago, and it's secrets are all but lost. Todays damascan effect blades are more about looks than function (although obviously the outer layers are there to clad and protect the carbon steel core)

                                                      1. re: Soop

                                                        Damascus barrelled shotguns were common;ly made in the US well into the early 1900s. Basically coils of wire formed around a mandril and forged. There were a lot around, so that through the 60s one had to be careful not to use high pressure modern loads in Damascus barrelled shotguns.

                                                        1. re: Soop

                                                          There are numerous blacksmiths who make high quality Damascus blades the traditional way, not clad. Search blacksmith + Damascus to start and several show up!

                                                          1. re: meatn3

                                                            Damascus steel is two different things. The pseudo-mythical steel made in Damascus that happened to look pattern-welded, and the name 'nickname' for all pattern-welded steel.

                                                            The rippled effect of the steel is often called Damascus, but it's supposedly not 'true' Damascus steel (if such a thing ever truly existed).

                                                            Too much trivia floating around in my head. :)

                                                            1. re: Ninevah

                                                              Correct. The mythical steel you mention is called wootz steel or wootz damascus. Pattern welded damascus is a different (and also old) technique that happens to look similar to the original wootz damascus and was never lost to the ages.

                                                              There are a few highly regarded custom knife makers working magic with skillfully forged pattern welded damascus - Bob Kramer, et al. Though as far as performance qualities go for knife-making, it's not any better than various other high quality modern steels.

                                                              1. re: cowboyardee

                                                                Nice. Wootz. Thanks. :) I've let my swordforuminternational.com membership lapse for awhile.

                                                  2. My Shun knives also chipped along the blade - we don't use them in the dishwasher, don't chop anything more complex than veggies, haven't been banged against rocks or chunks of metal, and store them on a magnet rack. I'm assuming it's something about the thinness of the blade - mine were much thinner than my friend's Henkels set.

                                                    For anyone else wanting to resharpen their Shun knives, you can send them back to Shun for sharpening. They'll re-edge them and mail them back you - you just pay shipping to get them to Oregon. That's where mine are, after Sur la Table said they were "one-sided" and they couldn't sharpen them.

                                                    1. One other possibility: Most Japanese knife fans will tell you never to steel your knives (at least with a ridged steel. Smooth steel, maybe). The metal, as others have noted tends to be more brittle, and the ridges really can rip the edges up. Maybe they were roughly steeled in the same way??

                                                      1 Reply
                                                      1. re: The Loaf

                                                        I have one Shun knife, it's my wife's favorite. They sent a dvd with it and it has a Utube link that shows Alton Brown using a steel, perhaps ceramic, on the knife. I use ceramic to touch it up about once a week and it works very well. Bifurcated is the word to remember, these are not damascus steel. They are rather brittle and damascus actually provides a pretty flexible blade. I mostly use knives that I bought for not much money in China Town (sorry if that's not PC) and they tend to be less brittle so they will handle a blow to the cutting board. The trick is to learn how to keep them sharp.

                                                      2. the knives were abused and the customer should have their "use of super-nice knives" license revoked. ******the customer left them soaking in water (sink, pan, etc) for over a week to produce the damage you describe****!!!!! ooh just thinking about it makes me SO MAD!!!!!

                                                        1. The reason the shun knives are chipping is not because people are misusing them. It has to do with storing the knives on a magnetic knife strip. In laymen’s terms… When the high quality steel in the shun knives are magnetized, it is causing the crystal structure of the iron and other metals that are magnetic (manganese, vanadium) to be attracted by the magnetic knife strip but the carbon and molybdenum are not attracted to the magnet. There for causing the magnetic crystals (on a microscopic level) to line up away from the non magnetic metals making the knife edge very brittle. So there you have it…Mystery solved. Shun needs to be aware of this and warn it’s consumers of this problem. Don’t store your shun knives on magnetic strips or even the wooden blocks with magnets inside.

                                                          15 Replies
                                                          1. re: jdunn342

                                                            Ooh, that's an interesting answer. My first set of three Shuns all had the chipping issues, and were stored on a magnetic knife strip. They were not abused/left it water for a week/steeled, etc. My replacement set have been stored in their wooden case for the past year, and haven't had any problems. I attributed that to a manufacturing change, but interesting to think that it could be the storage.

                                                            1. re: jdunn342

                                                              Ive studied metallurgy and this explanation does not seem very likely, but I wouldn't rule it out as impossible.

                                                              1. re: jdunn342

                                                                Interesting theory. Is it your own, or is there something published to support it?

                                                                Given that the regular Shun line uses VG-10 stainless and the Elite line uses powdered steel, it seems odd that both steels would respond in the same way, unless all hard stainless and powdered steels are vulnerable to magnets. Please elaborate...

                                                                1. re: alanbarnes

                                                                  What he says should apply to both steels. This is very interesting. Off to knifeforums!

                                                                2. re: jdunn342

                                                                  As with alanbarnes, I too would like to see some kind of report on this. As scientific as it may sound, you can't believe everything you see on the internet. ;-)

                                                                  1. re: HaagenDazs

                                                                    I think this may be the time period where people are starting to report the damage... there are now other threads with people with chipped japanese knives that stored them on magnetic strips.

                                                                    Perhaps it's some interesting combination of strong magnetic strip and very hard cutting surface.. we should do a survey...

                                                                  2. re: jdunn342

                                                                    I have had this blade chipping happened twice now. I store my Shun Santoku knive in the knife wood block that was included with the knife. And I did not soak it in the sink at all. Never use it to chop bones; my Henckle cleaver does that. I use a plastic scrub to clean it. In my opinion, I think the blade is just too thin. Besides, it's hard to think one would want to abuse a knife after spending $200.

                                                                    1. re: cookinginco

                                                                      Cookinginco-

                                                                      Have you read the rest of the new posts?There is a long list of questions, mine being do you ever cut bread with it?

                                                                      1. re: Dave5440

                                                                        I think this is the only thread cookinginco has ever posted in, so it may have just been to generate "discussion" among us geeks.

                                                                        Or maybe they're at work & can't get back here right away....

                                                                        1. re: Eiron

                                                                          True , but they experienced chipping as well without the obvious abuse reasons

                                                                          1. re: Dave5440

                                                                            Yeah, that kind of claim (along with the posting history) always raises a red flag for me.

                                                                            Perhaps I'm just too cynical?

                                                                            1. re: Eiron

                                                                              Perhaps I'm just too cynical?

                                                                              Aren't we all, symptom of life I think

                                                                                  1. re: Chemicalkinetics

                                                                                    Oh doctur, you err once , 99% of replys are kept in my grey matter but it's not due to being cynical

                                                                    2. So far, the guys on Knifeforums are unconvinced:

                                                                      http://www.knifeforums.com/forums/sho...

                                                                      No actual experience of damaged blades though.

                                                                      3 Replies
                                                                      1. re: Soop

                                                                        Ktulu64 said is better than I did,

                                                                        Quote, Knife blades are basically crystalline matrices / lattice. The carbides are held in an iron crystal structure (either interstitial or in substitution). Until you break (or sufficiently elongate) these crystal bonds, the carbides are unable to migrate. You can physically remove material (grinding / sharpening) which removes some of the metal and allows the carbides to migrate or fall out completely, or you can heat up the blade enough to elongate the bonds and let the interstitial carbon escape its crystalline prison. How a magnet (short of an inductive coil) could affect the crystal structure of the blade is beyond me.

                                                                        So no putting your knives above your induction ranges (they probably have so many safety features they wouldn't do anything...but then, you never know, those safety features just might not work)
                                                                        Unquote.

                                                                        1. re: Soop

                                                                          This is purely anectodal and I know nothing about the science involved. However in our store we did replace our old display magnets with much stronger ones last fall. (The weight of the handles of the Ikons were dragging them down the magnetic bars so we had to get newer stronger ones).

                                                                          Anyway, I've noticed in the last 6-8 weeks very small chips along many of our display Shuns - both the Classics and the Elites. This is a new problem we've had that we never saw with the old magnets. We've passed the information along to our corporate folks with pics but who knows what if anything might be done about it. Now in our case we're pulling hte knives off the wall several times a day and no matter how careful you are in many cases they tend to "slap" against the magnet because of the strength of the magnet. We've asked all our associates to be very careful.

                                                                          As for the knife in the original post...the customers claimed they were stored in blocks. Who knows what the case is. We still rarely get customer returns on Shuns with chipping and the severity of htat particular case was definitely an anomoly.

                                                                          1. re: ziggylu

                                                                            some blocks have magnets in them... meanwhile I wouldn't be all that surprised if the anecdotal evidence eventually leads to something (it often does). Perhaps it has to do with the strength of the magnet?

                                                                            It is, by the way, accepted that strong magnetism will affect metals in various ways. See:

                                                                            http://physics-animations.com/Physics...

                                                                            http://www.springerlink.com/content/x...

                                                                            http://sciencelinks.jp/j-east/article...

                                                                            http://ieeexplore.ieee.org/Xplore/log...

                                                                            http://www.mrs.org/s_mrs/sec_subscrib...

                                                                            http://adsabs.harvard.edu/abs/1921PhR...

                                                                        2. It appears that my original post got lost when the computer froze and went batty.

                                                                          My paternal grandfather had a sharpening wheel--foot pedals included--as well as a multi-sided stone he used to sharpen knives. The older ones looked like carving knives (formerly chef knives). My mother used a sharpening stone. If they're good knives, they can be sharpened until they're ice picks.

                                                                          But these were ancient knives from before I was born. Newer knives seem to be flimsier, and I don't have the space or the expertise to use a stone. If you know of a hardware store or notions shop which has sharpening days (call first), try them, as it's a fairly large nick you're referring to if the blade is salvageable.

                                                                          2 Replies
                                                                          1. re: Caralien

                                                                            No, I've seen that before... there was another, similiar post. Maybe you put it in there?

                                                                            1. re: Soop

                                                                              I realised that after the fact--confusing 2 separate posts on dull knives made the same day.

                                                                              Oops.

                                                                          2. ziggylu

                                                                            Curious about your remark, "I asked if they'd been doing a lot of sharpening thinking maybe the edges had gotten really brittle and unstable and were crumbling from that." I have an (extremely low-end) Hiromoto ($25 or so), about 15 years old, and it's been sharpened a lot with a V sharpener. Lately I've been getting chips along the blade and I can't seem to sharpen them out.

                                                                            Is it possible that sharpening too much can actually destroy a blade? If so, why does that happen? I thought, as Caralien said, that good knives could be sharpened until they're "ice picks." I mean, I know sharpening on a wheel can un-temper the blade because of the heat generated, but I can't believe that I could have produced anywhere near the necessary heat by hand on a V sharpener.

                                                                            Or is it just that I'm using the V sharpener? Those are supposed to be idiot-proof but I've been known to circumvent supposedly idiot-proof systems every now and again.

                                                                            There are other issues involving past use of grooved steels, cutting technique, etc. but that doesn't explain why the nicks, if anything, get WORSE after sharpening.

                                                                            2 Replies
                                                                            1. re: happy_c

                                                                              The problem with idiot-proof things is that the idiots are getting smarter :-)
                                                                              Just a guess, but I think I may be right, that the V sharpener leaves little teeth in your blade. Think of a mini-saw. These teeth are actually fault lines that could migrate up into the blade. Like I said, just a guess.

                                                                              1. re: billieboy

                                                                                It's probably your sharpener rather than the blade. Think how hard the metal on the sharpening wheels would have to be not to be affected by rubbing against the knife constantly.

                                                                                Plus, the sharpening wheel has less surface area than a large blade which could mean it's basically rotating twice or thrice the length of the blade.

                                                                            2. I've seen oodles of knives with the same damage you describe - in countries where people have maids. Take a perfectly good knife and you can have it chipped and deformed in days. I've never had a maid and don't have the problem.

                                                                              Of course other explanations are possible: the knife got near a microwave; the knife cut through something that had HFCS in it; pesticide residues affected the metal; a nefarious plot by agribusiness; chemicals escaping from plastic wrap ....

                                                                              1 Reply
                                                                              1. re: Sam Fujisaka

                                                                                Or that it cut through a product that cost exactly the same as it used to but now you get less of it?

                                                                              2. This is indeed strange. But, like every issue, these is a resolution. My first bit of advice would be to send any knife back to Shun if a problem arises. If I were in charge, I would want to know about problems with my product regardless of where the fault may lie. Storing these knives of a magnetic strip should not comprimise the integrity of the steel, as stated earlier (Vanadiam is NOT magnetic, and Manganese is only ferromagnetic after special treatment, so a magnetic strip would not interrupt the lattice of the molecules). More likely the customer, if storing their knife on a magnetic strip, is mishandling the knife when placing it on or taking it off the strip (i.e. if you pull it off fast and twist the knife in the process, scraping the edge last), If there were a specific metal issue, it could be Chromium. Cr is a very hard, extremely brittle material. Maybe some steel batches were released with too much Cr, and not all who are experiencing this are coming forward. I do not know where Shun get's there steel from. However, There are a small handful of mills throughout the world that supplys virtually all of the industrial metal. While they may forge their own blades, I seriously doubt they do their own mining and milling.

                                                                                At my company, about a year ago, we experienced a very bizarre circumstance regarding our 304 Stainless Steel. Now, I know we are talking about two very different materials (Shun's VG-10 vs. my 304), but hear me out. We continued to find air leaks through the material. After weeks of rechecking material analysis certs, and demanding our customers to remake parts from different steel stalk, we had the material analyzed. What we found were abnormal concentrations of Cesium. Cesium should not be in steel. Not 4130, 1018, 303, 304 or 316...it should not be in there period. During forgeing of our steel, the Cesium had not cohered and created tiny air bubbles in the material. I have never seen this, nor has anyone I work(ed) with seen this. After another couple weeks of tracing, we found the material to come from a mill in Spain. By this time we had switched to 316 anyways.

                                                                                So like I said, if I were running things over at Shun, I would want to know if something like this was happening and I would want to see it back so I could analyze it. There is only so much we can do writing about it here.

                                                                                1. I purchased two Shun knives about six months ago, and both of them chipped within a few weeks. The paring knife even chipped on the end of the spine at the tip of the knife. It was so strange - I never used my knives on anything other than wood, I hand washed and dried them (I don't even have a dishwasher), stored them in a block, and I never abused them while cutting (that doesn't even make sense with a paring knife). I'm the only one who used them because my roommate doesn't cook.I sent them back, because I figured something was wrong with their production. I just can't understand why a knife would chip along the spine.

                                                                                  12 Replies
                                                                                  1. re: gaudi347

                                                                                    Hi Gaudi,

                                                                                    Do you mean chipping at the very tip of the knife? That is one of the most common place for chipping because that is the weakest point. I think a lot of people have complainted about the Shun edge finish. It chips readily. On the other hand, many people said once they have sharpened and restore the edge, it does not occur again. So something to do with factory finish.

                                                                                    I have my Shun bread knife chipped at straight/flat section near the knife heel. I resharpened it and it is fine and have not chipped since. Hope you better luck.

                                                                                    1. re: Chemicalkinetics

                                                                                      No, it chipped on the spine about a quarter of an inch from the tip. It was like something took a bite out of it. Very, very strange. I have had a Suisin Inox Gyutou for the last year, and had absolutely no problems.

                                                                                      1. re: gaudi347

                                                                                        "The paring knife even chipped on the end of the spine at the tip of the knife"

                                                                                        "it chipped on the spine about a quarter of an inch from the tip."

                                                                                        I think you are the first person who told me about chipping at knife spine. That is very unusual indeed.

                                                                                          1. re: alanbarnes

                                                                                            Why, of course. That makes a lot more sense.

                                                                                            1. re: alanbarnes

                                                                                              But wasn't he talking about a chip on the spine of the paring knife?

                                                                                              That is a feat of sabrage I would love to see!

                                                                                              1. re: alanbarnes

                                                                                                My small duplex with two dogs and a cat constantly underfoot means that I would never have a chance to use my knife like that, even if I felt that I could treat something so expensive in that way.

                                                                                                1. re: gaudi347

                                                                                                  You do understand where alanbarnes is coming from with the suggestion of sabrage, right?

                                                                                                  1. re: Chemicalkinetics

                                                                                                    I understand, but I had explained earlier how I treated my knives.

                                                                                                    1. re: gaudi347

                                                                                                      "I understand, but I had explained earlier how I treated my knives."

                                                                                                      I understand that you have insisted that your two Shun knives chipped at the knife spine despite with great care. What I find very surprising, and I suspect alanbarnes as well, is that how a knife can chip at the knife spine instead of at the knife tip or the knife blade. This is why I said that it is most unusual indeed.

                                                                                                      Alanbarnes said "sabrage" because some people use the spine of a knife to perform sabrage.

                                                                                                      I suspect that you do not understand the location of a knife spine. A knife spine is not an obvious place for chips, not for two knives in a row. Here are two pictures of a knife and please take a closer look at the pictures and verify indeed the chips occurred on spines of your two knives:

                                                                                                      http://www.webstaurantstore.com/site_...

                                                                                                      http://cutlerynewsjournal.files.wordp...

                                                                                                      1. re: Chemicalkinetics

                                                                                                        Only the paring knife chipped on the spine. The chip on the spine is what made me return the knives (even though both were chipped on the blades as well). Even if they somehow had been mishandled in the two weeks I had them, I doubt I would have been able to damage them like that and not remember it. As I said before, my gyutou is doing fine, so I don't really think it's a EBSAC type of thing. I don't want to sound childish, but I'm not lying about this for some ulterior motive. I honestly was hoping to find out how something like that could have happened.

                                                                                                        1. re: gaudi347

                                                                                                          Gaudi,

                                                                                                          Understand. I was under the impression that only the spine chipped, but not other places. Now, I know the knife edge also chipped. It is easy to see how a knife edge chips because a knife edge is regularly hitting something. In order for the knife spine to chip, the knife spine must have impacted with another object. Otherwise, it would be pretty tough to have the knife spine to chip.

                                                                                                          The good thing is that you have a gyuto which works for you.

                                                                                      2. One form of physical abuse that may cause it is 'leverage'. So cut into something hard and then wiggle the knife side to side. That may cause those symptoms. If someone else wishes to experiment and report back then I would like to hear.

                                                                                        One of my shuns has a bone-related nick.

                                                                                        I was the bone-head that did it.

                                                                                        3 Replies
                                                                                        1. re: Paulustrious

                                                                                          Also, these japanese knives don't like being used to rock cut much. That's very hard on the edge. Push or pull cuts are best.

                                                                                          Also, using a wood cutting board isn't sufficient. Is it end grain. Is it a good wood (dang that sounds nasty).

                                                                                          I wouldn't recommend bamboo cutting boards at all.

                                                                                          1. re: deeznuts

                                                                                            Deeznuts,

                                                                                            You know. I read this all the time -- push cut is friendly than rock chop. I personally do push cutting because it is more natural for me and for my knives. As such I don't really sit down and think about this, but a week I start wondering: why would rock chopping be worse? I almost post a question here, but didn't. Now that you bought it up, I figure I should ask.

                                                                                            Think about it, whenever we push cut using a knife, the knife makes a sudden impact on the board, which is why it makes this "bo, bo, bo" or "ba, ba, ba" sound when we use a nakiri or usuba or Chinese chef's knife.

                                                                                            On the other hand, a rock chop is rotating/rolling the knife edge, rocking the knife back and forth, so there should be less of a sudden impact. Or am I missing something here?

                                                                                            1. re: Chemicalkinetics

                                                                                              The sound you hear is usually because of the whole edge hitting the board at once. Rock cutting you probably don't hear the same sound because the whole edge is not coming into contact all at once, but you use a lot more force. Think about it, when push/pull cutting your motion is pretty precise, you kind of know you're going to hit the board and it stops. With rock chopping usually it's a pretty violent motion.

                                                                                        2. I had a slightly different Shun knife problem I was wondering if anyone had any ideas about. A month after I got my new single-bevel Shun knife, I noticed little brown circles, likely rust, on the flat side of the blade. I've only used it in slicing raw fish and a few pot roasts so I was baffled and disappointed that this high-end knife would rust so quickly. I sent it back to Shun and they managed to buff out most of the rust but couldn't tell me why this happened. We always hand wash and towel dry our knives before returning it to the knife block. Never had this problem with our Wusthof or any other knives.

                                                                                          3 Replies
                                                                                          1. re: redbeanbun

                                                                                            redbeanbun,

                                                                                            Unfortunately, this is quiet common and there is another post with which the original poster also mentioned it.

                                                                                            http://chowhound.chow.com/topics/527897

                                                                                            At the end, I believe the poster understands the tradeoff and appreciates the Shun knives.

                                                                                            Applehome also made a good point a few posts above:
                                                                                            "I've always said that people who want to invest in good knives need to learn how to maintain them. You don't treat your Porsche like a Chevy, or your Rolex like a $15.95 Timex. If you're not willing to put in the time and effort, stay with the Solingen steel, (Wustoff, Henckels, Forschner/Victorinox) or the 440A steel on your Cutco."

                                                                                            Your single-bevel Shun knife is probably the Shun Pro. For Shun Pro, the entire blade is made of VG-10. VG-10 is a great stainless steel. It can be hardened to high Rockwell and it is easy to sharpen. VG-10, however, is not the most stainless of all stainless steel. If having a extremely "stainless" knife is the important aspect to you, then Shun is not the choice for you and you probably should look elsewhere for your future knives. On the other hand, if performance is more important, then Shun is a great knife.

                                                                                            Wusthof (most) knives are made of X50CrMOV15, which is a steel with great corrosion resistance, so it is very stainless, but it is not considered as high performance as VG-10.

                                                                                            My guess is that the knife was not completely dry or the wood block has water in it -- which is not uncommon. You can easily remove minor rust stain on your own. In fact, Shun Pro knives are built as such that they are easily to self maintain.

                                                                                            1. re: Chemicalkinetics

                                                                                              hah. all our kitchen equipment are treated like pampered children, mainly because it takes me months to research and decide on a new or replacement piece. but obviously i missed some info on the shun knives, probably because i've never seen rust on a knife before and it wouldn't have occurred to me to look into it. 'knife block' might not be a good description - we have one of those open wide-slot, in-drawer knife blocks mainly because of dust and mildew concerns. at least now that I know the Shun is more sensitive to rust issues, we'll keep a keener eye on it. thanks!

                                                                                              1. re: redbeanbun

                                                                                                Redbeanbun,

                                                                                                I have a Shun knife too. I think you want to take care of them more than Wusthof, but I don't think you should need to pamper them too much. I think a few posts here states the Shun knives acquired stains, but not full blown rust. Yes, I agree. To remove minor stain and rust, you can use Bar Keeper's Friend. No hard scrubbing is required. Dissolve BKF into water and use the solution to dissolve the stain and rust. By the way, I find it is better for your knives if you clean it with mild or just water instead of aggressive cleaners. Best wishes.

                                                                                          2. I had the exact same problem with my Shun Stainless Steel 8 inch santuku, microchips on the edge.

                                                                                            I have 2 Mac knives (ultimate and professional) which I have used for years without problems

                                                                                            I cut only veges and boneless meats, on a plastic cutting board, hone with a gentle touch on a ceramic rod, store in plastic knife guard, always hand wash....

                                                                                            the chips looked like I was hacking wood with these knives. i sent it back to the factory for an inspection, they put a new edge on and said nothing is wrong with the metal. 2 weeks later the chips reappeared.

                                                                                            I am definitely not a knife abuser, my Mac's which are sharpened to 13 degrees has never had a chip.... the Professionals are rockwell hardness 60-62 so I know how to handle hard brittle knives. there HAS to be something wrong with the shun metals.

                                                                                            1. Sorry to "chip" in so late...

                                                                                              My wife LOVES her Shun 7" Santoku. We've had it for about a year, and it started chipping very early... within weeks. It is now chipped all up and down the blade. I don't know whether or not Ziggylu's clients abused their Shuns, but there was quite a bit of "ass-ume"-ing going on, so thought I would report our experience.

                                                                                              So in response to Cowboyardee and Eiron's questions:
                                                                                              1. What do the chips look like? They range from 0.5 to 3 mm in length, about 0.25 to 0.5 mm in depth, and are rather evenly distributed along the blade.

                                                                                              2. How and how often do you sharpen? Do you use a steel in between sharpenings? How long after sharpenings do chips typically appear? No sharpening yet, no steel.

                                                                                              3. What type of cutting board do you use? Our favorite cutting board is a soft plastic, but we also have harder plastic ones.

                                                                                              4. How do you cut most things - do you use a rocking motion? Chopping? Do you cut fast or slow? Chopping, fast.

                                                                                              Others have mentioned no magnetic strip, a knife block, no moisture that sticks around; it's been kept in 0-20% humidity.

                                                                                              My wife still loves the Shun's scalpel-like blade (it still slices through veggies like butter). Knife snobs may say what they will about Cutcos, but ours have zero chips after 10 years of service and carefree maintenance (toss it in the dishwasher, bang it around), and I've personally heard from people who say the same after 20-40 years. They need to be sharpened, and I do wish they had more comfy handles, but there's no arguing with the lack of maintenance.

                                                                                              David

                                                                                              20 Replies
                                                                                              1. re: davidahn

                                                                                                Hi david,

                                                                                                Thanks for adding to the collective knowledge base!

                                                                                                I love my Shuns as well, & I think I can group the Kanetsune with them (same steel & layer construction). I also like our one Cutco (5" santoku) more than I often admit here. But it's easy to keep a good edge on it, so I'm sure that helps my opinion. I also like having a completely different knife shape than the others, so it's always a different experience using the Cutco.

                                                                                                Do you ever plan to get an end-grain wood cutting board? It would be interesting (to me) to see if the chipping continues at the same rate, or is reduced (or eliminated?) by that one change.

                                                                                                How do you plan on removing the chips from the Shun? And have you never had your Cutcos sharpened in 10 yrs? I sharpened a co-worker's Cutco chef knife & paring knife. She'd had them for about 20+ yrs & had only ever used one of those table-top "rolling" sharpeners (it looks a little like a yo-yo?). She thought the edges were still "sharp enough," even though they were extremely toothy & jagged.

                                                                                                1. re: Eiron

                                                                                                  Eiron, to be honest, the chipping seems to bother me a lot more than it bothers my wife, who wields it much more often and more skillfully than I. :) I read most of the posts above, and several say that sharpening will solve the problem; if not, I may consider returning it to Shun. Also, you may have heard how my wife is wont to slam doors and drawers in my cookware thread. She chops very quickly and precisely, but I wonder if she doesn't use more force than is necessary, and if the soft cutting board is gripping the edge while she's starting to slide the knife over for the next chop.

                                                                                                  We are in fact getting two free 12.5-lb. walnut cutting boards courtesy of Kohler... just for buying $1500 worth of sinks (a 45" and a 33" Kohler Stages sinks). I have always worried about the relatively microbe-friendly nature of wood, which would not have been as big an issue in the high desert where we've lived for the past 10 years and where things don't stay damp, but in our new San Diego home, humidity is definitely more of an issue.

                                                                                                  We've never had the Cutcos sharpened; they are definitely a lot duller than when new, and that's probably a big factor in our soft plastic cutting board preference, so we can lean into it and still cut through our veggies. Until recently, we only had a single 8" chef so we couldn't send it in, but now we have a Cutco santoku (newer and sharper) and the chipped Shun santoku (sharpest but chippy), so we should be able to do without the chef for the sharpening. Also the Cutco rep offered to come out to sharpen them, but then we feel obligated to buy more. :)

                                                                                                  We will see how the Shun does with sharpening, but I'm thinking our cooking style leans more toward German steel for its more forgiving nature. What do the Hounds think of Wusthof's Ikon Crème or Culinar lines? (Either would meet our new modern architecture.) We're looking for the most bang for our buck, though on the higher end. We're looking for that point on the price-performance curve where prices keep going up but quality starts to flatten out. :) (Isn't everyone?)

                                                                                                  David

                                                                                                  1. re: davidahn

                                                                                                    Since you are in San Diego come down to the Little Italy Mercato farmers market on Saturday. I'm set up one the eastern end opposite the dog park and let me take a look at them.

                                                                                                    Treat yourself to the killer tamales on that end also.

                                                                                                    Jim

                                                                                                    1. re: knifesavers

                                                                                                      Well we're renovating the San Diego house so all our knives are still in Apple Valley. But once we're moved in, we'll definitely check you out!

                                                                                                    2. re: davidahn

                                                                                                      'Also the Cutco rep offered to come out to sharpen them, but then we feel obligated to buy more. :)'
                                                                                                      ----------------
                                                                                                      Realistically, you may be obligated to sit through another sales pitch.

                                                                                                      But please, think of the sharpening as included in the price of your knife. You already paid for it. Compare the price tag for Cutco to knives of similar quality (forschner, etc) - that big markup is for the free sharpening. Do not feel bad about using it.

                                                                                                      1. re: cowboyardee

                                                                                                        You're right about the sharpening being included... I know we paid for it, and we shouldn't feel guilty about using it. And our Cutco rep's a super guy so we don't mind hanging with him while he sharpens/makes his pitch.

                                                                                                      2. re: Eiron

                                                                                                        Eiron,

                                                                                                        I think I might have asked you this, but I forgot. Since your Shun and Kanetsune are both made of VG-10 core steel, do you have any preference regarding the edges? Thanks.

                                                                                                        1. re: Chemicalkinetics

                                                                                                          I'm suprized VG10 chips like that it's not know to be chippy, but if DD just gets the shun sharpened to 35~40deg I'm sure it would stop chipping and the edge last a long time

                                                                                                          1. re: Dave5440

                                                                                                            Most of the VG10 I've seen tends to be a little on the chippy side.

                                                                                                            Some of the higher end stuff - kanetsune, hattori, etc are reputed to be tempered better and less chippy. But DD's description of microchips sounds about right for a Shun that's never been sharpened and given a little time for those microchips to accumulate. Of course cutting technique and pressure figures in, but even putting aside the difference between pushcutting and rock chopping, some people just seem to use a motion and pressure that's harder on a knife edge than others.

                                                                                                            Two upsides of sharpening:
                                                                                                            For one, sometimes the metal behind the edge is a little less brittle, and the chipping reduces in frequency once the factory edge is sharpened away.

                                                                                                            For another, if you sharpen often, you don't give microchips as much time to accumulate. AND you don't do as much cutting with weakened steel.

                                                                                                            1. re: cowboyardee

                                                                                                              sounds like a plausable explanation , I have no vg10 so I am going by what I've read, but from what I know about hardening and tempering it would be extremely difficult(if not impossible) to get a different temper on a blade as thin as a shun or any blade for that matter, the only explanation could be thicker therefore stronger

                                                                                                              1. re: Dave5440

                                                                                                                I don't think I'd call it a 'differential temper' as that would indicate intentional hardening of edge steel. If I had to guess, I'd say it has a little more to do with the shun factory sharpening and finishing process. Could be that the metal at the edge is already fatigued a bit or that however they sharpened it at the factory makes the edge a little weak or introduces a few micro-fissures in the steel or something.

                                                                                                                ...Or it could be all a sort of popular (among knife nerds) myth. It's something I've heard multiple times, but I have not personally experienced it. The tojiros I've bought weren't much different in terms of chipping before and after the first sharpening, anyway.

                                                                                                                1. re: cowboyardee

                                                                                                                  "Could be that the metal at the edge is already fatigued a bit or that however they sharpened it at the factory makes the edge a little weak"

                                                                                                                  A good point.

                                                                                                                  Cowboy and Dave,

                                                                                                                  On the other hand, we have many people have stated that Henckels Miyabi Kaizen (VG-10 core) knives are more chip resistance than Shun Classic knives. This is especially surprising because Kaizen is sharpened to a much lower angle at 9.5-12 degree per side, whereas Shun Classic is 16 degree. Yes, Shun is hardened to 61 HRC and Kaizen is 60 HRC, but really?

                                                                                                                  http://www.knifecenter.com/item/H3418...

                                                                                                                  Kaizen touts that it uses "double tempting" to tough the steel.

                                                                                                                  Another thing I am surprised is that who makes this for Henckels. All Henckels Miyabi knives are made in Japan. This suggests that Henckels realizes that it is behind in term of the Japanese steel technology and that it has to (a) buy an existing Japanese company or (b) source the job to someone and relabel the knives under Henckels.

                                                                                                                  If so, then why didn't that Japanese company goes toe to toe again Shun-Kai? Anyway, that is more of a business question.

                                                                                                                  1. re: Chemicalkinetics

                                                                                                                    Kaizen touts that it uses "double tempting" to tough the steel.

                                                                                                                    I would call this marketing doubletalk.

                                                                                                                    Yes, Shun is hardened to 61 HRC and Kaizen is 60 HRC, but really?

                                                                                                                    There is a reason all mid to high and custom knife makers specify a Rc range when stating what the knife hardness is, as even heatreating 3 knives(or anything for that matter) at once can vary a few points of rc. and a few points goes a long way in toughness of the steel. And really if Henckles or shun says rc 61 or 60 who is going to check(or can) at the retail end So if ad says 61 that means 60~62 to a high quality manuf. and 60 would be 59~61. This would also explain a lot of mixed reviews on how chippy their (insert brand) is compared their buddies exact same knife that's not chippy. Here's a good write up at Zknives with his discussion with a miyabi rep.
                                                                                                                    http://zknives.com/knives/kitchen/ktk...

                                                                                                                    1. re: Dave5440

                                                                                                                      "There is a reason all mid to high and custom knife makers specify a Rc range when stating what the knife hardness...."

                                                                                                                      I actually agree with you. My previous statement was about: Why is Henckels knives less chipper? Could it be because it is 1 HRC lower? Really?!

                                                                                                                      1. re: Chemicalkinetics

                                                                                                                        I think so or their QC is better, but there is something to the "ice hardening" bs they tout all the time, the ice bath doesn't harden but artificially ages the steel toughening it up to some degree, it makes a huge difference in aluminum but maybe even a marginal defference in steel would make a difference

                                                                                                          2. re: Chemicalkinetics

                                                                                                            Chem,

                                                                                                            I'm not sure I understand your question. Do you mean between the two different brands? Or VG-10 edges compared to something else? Or... ?

                                                                                                            1. re: Eiron

                                                                                                              Eiron,

                                                                                                              More about the first one. Between the two VG-10 knives (Kanetsune and Shun) do you notice any difference? Now, I remember your Shun is an utility knife, so it won't be used the same way and thus that alone can alter the impression. So it is probably not a good question.

                                                                                                              1. re: Chemicalkinetics

                                                                                                                Yes, I think the difference in knife types (chef vs utility (or gyuto vs petit gyuto, if you prefer)) makes any comparison very difficult. I'm partial to the Kanetsune, but that may have more to do with its ability to perform just about all of my cutting jobs extremely well than with any actual failing of the Shun. My wife uses the Shun 150mm petit quite a bit, much more than I do, so it may have more to do with grip (she doesn't pinch-grip) & fear (she's said a couple of times that our knives are "too sharp") than anything else. I do use the 100mm petit quite a bit as a fruit knife, but I've only sharpened that one once & it hasn't yet reached "edge nirvana"! :-) Still, the application is quite different from the Kanetsune, so I don't think that helps answer your question at all.

                                                                                                                I know that my cutting style has changed quite a bit in the past two years since getting thin, hard, sharp J-knives. I don't apply nearly as much pressure as I used to, & I now have several decent wood cutting boards. The last edge-grain board I bought (about 1-1/2 yrs ago) still shows hardly any cut marks. I'm sure the change in cutting style alone affects my impressions of edge qualities.

                                                                                                                1. re: Eiron

                                                                                                                  "fear (she's said a couple of times that our knives are "too sharp""

                                                                                                                  :)

                                                                                                                  Good. Fear demands respect. Respect for knives is always good. Both of the times I semi-seriously cut myself because I didn't respect the knives (or I didn't think what could possibly happen)

                                                                                                                  "I don't apply nearly as much pressure as I used to"

                                                                                                                  Same here. I used to apply a lot more force/pressure when I cut. I know it because when I first switched to these hard steel Japanese knives, I would cut into the wood cutting board and drag the knife edge across.

                                                                                                      3. I bet they may have a bamboo cutting board but someone used them on a granite counter. Kids, housekeeper...someone not involved in the purchase most likely.

                                                                                                        1. I don't know the reason behind it, but I've seen it many times with Shun knives, basically I think they are poorly made and extremely overrated. I would happily use a set of Victorinox heck even buy a set of them before I paid for Shun.

                                                                                                          In my chef days I went through every major make of knives and when it was time to settle and buy my self a set I was torn, either Sabatier or Global. It wasn't too hard though thanks to being fortunate enough to get the opportunity to using both makes literally in a two day, back to back job.

                                                                                                          I was already a fan of both but this work was a great chance to use both makes and literally made my choice for me. You want high quality, easy to maintain knives, in my honest professional and personal experience you can't beat Global. Even for home use three or four Global knives coupled with their own diamond steel. Plus I found the angle of the Global steel makes maintaining a sharp edge easier.

                                                                                                          1. I've been trying to figure out what is causing this and am not finding a common factor to any of it.

                                                                                                            So far, over the last year, every Shun in their lineup, and not just their VG-10, lower ends and mimicked Chaphalons are coming in chipped. Some minor, some substantial.

                                                                                                            I've asked the owners the list of questions .. no common ground.

                                                                                                            Also seeing more Globals coming in chipped from tip to heel.

                                                                                                            I rarely, if ever come across this with standard European style metals and edges.

                                                                                                            I'm regrinding and telling my clients to let me know once chipping starts again in hoped that I can find a pattern.

                                                                                                            So far no returns or calls.

                                                                                                            Now I have been applying a mild Convex to them. Still hanging around 16°, but beefing up the shoulders, so am eager to see if it helps, as well as going over steeling with clients, maintenance and handling, and have been recommending a 1200 grit ceramic rod using a light touch.

                                                                                                            My gut is telling me the steel used is just not cutting it at extremely acute angles.
                                                                                                            May be great for meat, fish but hard veggies and herbs or hard repeated pounding on a board for parsley might even cause the pitting/chipping.

                                                                                                            Then again, none of it explains chips from tip to heel.

                                                                                                            1 Reply
                                                                                                            1. re: nigelx

                                                                                                              Nigel, thanks for your post! Awesome to hear from someone with so much experience in these matters. I'm especially intrigued because we were going to switch to Global because of good things we've heard and no real chipping issues reported, until your post.

                                                                                                              We use plastic cutting boards, though we will soon start using Walnut end grain cutting boards, and my wife (the primary cook) is a fast chopper, no rocking. I may do some rocking when I help.

                                                                                                              As far as your question about veggies, we're vegetarian so chop exclusively veggies and fruits, which you say may be responsible, and some of them are quite resistant to being cut.

                                                                                                              But my wife still loves her Shuns, and the chipping doesn't seem to affect their effectiveness at all. We will have to get the Shun sharpened professionally to see if the chipping stays gone. Please keep us posted on whether you see re-chipping after sharpening!

                                                                                                            2. Were the knives stored in a magnetic strip /stand?Magnetisation (or the effect of a strong magnet nearby) of the knife blade. Magnet influence at a molecular level. SO DO NOT STORE EXPENSIVE JAPANESE KNIVES ON A MAGNETIC KNIFE STRIP!! I keep my hand crafted Japanese knives in individual boxes. I do not subject them to heat. Even if they are "stainless" they are not meant to go inside dishwashers or soak in sinks overnight. Only flat whetstone with water should be used to sharpen. Everything else ruins it. It is possible that it is a bad batch with faulty tempering but if that is the case then many more customers would have the same problem. Knife should never be "wiggled" during a cut motion. To those who praise Wusthoff and Henkel all I can say is that it is due to the way the cut motions are made one feels a difference. Japanese knife are designed to "part" what you are cutting "effortlessly". It is more of a slice than a cut. One has to use more energy (burn more calories) to cut a carrot with a heavier Wustoff or Henkel or similar thicker knife. There is no equivalent to a Japanese nakiri usuba (vegetable knife) with our range of crude "chef" knives.

                                                                                                              I have used Shun briefly. They are a pleasure to use if I recall. I think Shun and Global are among those knives with better ergonomics and performance philosophy than Wusthoff, Sabatier, Henkel etc etc.. however, these heavier knives are more resilient towards rough and "improper" use.

                                                                                                              14 Replies
                                                                                                              1. re: SomersetDee

                                                                                                                there is actually no credible scientific evidence that backs this up... quite the contrary for that matter, both scientifically and practically.

                                                                                                                1. re: JBroida

                                                                                                                  <there is actually no credible scientific evidence that backs this up>

                                                                                                                  Which part were you talking about?

                                                                                                                  The part about magnetic strip? The part about dishwasher? The part about Japanese knife? The part about Wusthof and Henckels?

                                                                                                                    1. re: scubadoo97

                                                                                                                      That is odd. Because I think that all of them can be correct -- given the right context. The magnetic strip is probably the weakest assetion, but it can happen at the right conditions.

                                                                                                                      1. re: Chemicalkinetics

                                                                                                                        I should take back that blanket statement.

                                                                                                                        I guess I was referring more to the magnetic influence and moderate heat

                                                                                                                        Certainly poor technique in cutting and poor sharpening can and will lead to an edge chipping

                                                                                                                    2. re: Chemicalkinetics

                                                                                                                      magnetic stuff... the only damage comes from people putting them on or taking them off with too much force and/or twisting.

                                                                                                                    3. re: JBroida

                                                                                                                      Hi JBroida, I think I know you from somewhere. (You sell fine hand-crafted knives if I remember?)

                                                                                                                      Possible "Scientific proof" number 1:
                                                                                                                      When I have left my screwdrivers and metal tools carelessly touching a magnet, they have got magnetised themselves. Which now means that when I pick up the screwdriver the screws are attached to it often getting strewn on the floor etc. So how did this happen? The only way that this has happened is because the molecules inside the screwdriver have somehow moved (turned) and got realigned. I suspect that such realigning can easily undo fine tempering.

                                                                                                                      Since a thin and light japanese knife relies upon its tempering for it to be useful. I think we should do all we can not to loose that tempering.

                                                                                                                      Hard tempering can also be easily lost by heating ( even lightly I suppose) if I understand correctly.

                                                                                                                      1. re: SomersetDee

                                                                                                                        "I suspect that such realigning can easily undo fine tempering."
                                                                                                                        ________
                                                                                                                        I've heard this kind of speculation before. But it just doesn't match up with observed experience.

                                                                                                                        I have Japanese knives - a good many, several of them thin, most of them quite hard. And I use magnetic knife strips. Have for years. My knives have no temper problems. Take an extremely sharp edge easily, and hold it well.

                                                                                                                        I have friends who use Japanese knives and magnetic strips. They have no problems either.

                                                                                                                        I sharpen knives for a few professional cooks who have magnetic strips and Japanese knives. No problems there either.

                                                                                                                        Kitchenknifeforums.com and knifeforums.com are absolutely filled with people who like and collect Japanese knives and who push them to the edge of their capabilities in terms of sharpness and performance... And magnetic strips are popular and widely used by those same enthusiasts.

                                                                                                                        If you've had knives lose their temper for you, a magnetic strip would be one of the least likely causes.

                                                                                                                        IME, most times people think they've lost their temper, the real culprit is poor sharpening. Though exposure to high heat can certainly do it. Also never seen a knife lose its temper from being in a dishwasher, though they can certainly get dinged up or rusted in one. Maybe if you washed your dishes in an autoclave or something...

                                                                                                                        1. re: cowboyardee

                                                                                                                          "Maybe if you washed your dishes in an autoclave or something..."

                                                                                                                          Great, that's all I need -- yet another compulsion to add to the list I've got...

                                                                                                                          1. re: Eiron

                                                                                                                            Hy Eiron: "'Maybe if you washed your dishes in an autoclave or something..."'

                                                                                                                            My B-I-L is a pathologist, and he's given me a box full of microtome and other blades that have been autoclaved tens of thousands of times. Absolutely no effect on temper or edge retention. Aside: One of the cool things he gave me is an old, long, specialty, brain sectioning knife, which looks like a straight-edge carver except for the aluminum 'clavable scales. Wickedly sharp, and fun to tell guests about after a meal of carved meat!.

                                                                                                                            Aloha,
                                                                                                                            Kaleo

                                                                                                                            1. re: kaleokahu

                                                                                                                              "One of the cool things he gave me is an old, long, specialty, brain sectioning knife, which looks like a straight-edge carver except for the aluminum 'clavable scales. Wickedly sharp, and fun to tell guests about after a meal of carved meat!."

                                                                                                                              So then, you use this to carve the meat at parties! :-D

                                                                                                                              Your sense of humor sounds a bit like my cousin's. He's a paramedic & has a 'news room' where he keeps the newspaper stories that include pictures of him at the scene of accidents. He'll show guests some of the clippings, & talk about one or two particularly 'interesting' calls, then serve up a meal of ribs...

                                                                                                                              1. re: Eiron

                                                                                                                                Of course. At least I used to... I later learned that even autoclaving isn't effective for destroying prions (e.g., those that cause Creuzfeld-Jakob aka Mad Cow). But I still like to bring the knife out with the serving platter.

                                                                                                                                It'd still prolly be safe--I'm not aware there's ever been a case of CJD anywhere nearby. But discretion being the better part of valor...

                                                                                                                        2. re: SomersetDee

                                                                                                                          i would advise you to posit this to a metallurgist and see what he/she says (having done this before)

                                                                                                                        3. re: JBroida

                                                                                                                          Thanks everyone! Maybe I have been treating my knives way too delicately. I feel happy to learn that I dont have to be so delicate with them. I think I fuss over them way too much!

                                                                                                                      2. Ok, been running across this again and again with Shuns and Globals.
                                                                                                                        IMHO, they are not chips.
                                                                                                                        They are air pockets in the metal, bad mixes.

                                                                                                                        I have ground away old "chips", reprofiled the edge, only to find new "cjips" or rather holes.
                                                                                                                        Under a loop, thinning the edge to razor sharpness removes some metal, exposing these air pockets.
                                                                                                                        Closer examination showed dimples on the side of the edge.

                                                                                                                        Those dimples then manifest as chips it they show up on the edge.

                                                                                                                        That's the best I'm come up with and have confirmed with other sharpeners that they are experiencing the same thing, along with exposing new holes while ridding the old ones.

                                                                                                                        Some batches are much worse than others.

                                                                                                                        Just my 2 cents.

                                                                                                                        10 Replies
                                                                                                                        1. re: nigelx

                                                                                                                          I suspect that air pockets may be a bit inaccurate. What you're describing sounds more like something I've heard termed 'carbide tear-out.'

                                                                                                                          Hardened knife steel is a bit like concrete on a microscopic level. It's grainy - not uniform. Suspended in steel, there are a number of extra-hard particles or grains called carbides - hard chunks where carbon has bonded to some of the alloying elements in the steel. If the carbides in a steel are too large and/or unevenly distributed, you can make a sharpening pass wherein a larger carbide chunk (which is harder to abrade) gets pulled out of the edge of the knife entirely, leaving a tiny divot at the edge and leaving your knife less sharp than it was before that sharpening stroke.

                                                                                                                          I'm not a metallurgist, so my explanation might be a bit lacking, possibly even inaccurate - this is just what I've heard from talking to other knife nerds. Steels that have very fine and very even grain structures are steels that sharpen especially well, and vice versa.

                                                                                                                          I've sharpened a reasonable (though not a huge) number of globals and shuns, and haven't really experienced this problem with them specifically. Doesn't necessarily mean you're wrong - maybe I've just been lucky.

                                                                                                                          But I'm wondering exactly what you use to sharpen with, since that might also affect how likely it is that you pull carbides out of the edge rather than sharpening them down. I've heard that oilstones and arkansas stones can be a bit more likely to exacerbate this problem than waterstones since the abrading surface doesn't grind away (unlike waterstones) and a hard grain of carbide is more likely to get 'caught' and torn out. Likewise, cracks in a stone might catch the edge more easily, or even a high corner or edge on the stone might do it.

                                                                                                                          1. re: cowboyardee

                                                                                                                            Cowboy,
                                                                                                                            I use a variety of things to sharpen, stone, diamond, belts, leather, paper and rogue.
                                                                                                                            In every grit imaginable.

                                                                                                                            Upon inspection, I can see with loops new dimples form in the final stages, say on a belt at 1200 grit, where the passes are very lite and the metal removal a powder.
                                                                                                                            These are not always on the very apex of the edge, they can be, but many times on the sides of the edges.

                                                                                                                            Almost as if just enough metal was rubbed off to expose what appears to be a hole.

                                                                                                                            The lite touch of the final stages I don't believe pulls anything out but rather exposes, but I have no real way to tell aside strong loops.

                                                                                                                            The metal can be smooth and clean, then when doing final passes, even on paper wheels and jeweler's rouges, suddenly a hole will for on the apex or side wall.

                                                                                                                            Always circular in form, sizes vary.
                                                                                                                            On the apex, they look like chips, until you look through a loop, and see that it is circular or oval, same when they get exposed on the side wall of the edge.

                                                                                                                            Oh, I've also had them come in batches.
                                                                                                                            1 set, no problems.
                                                                                                                            Another set, consistent pits/holes/tear-outs.

                                                                                                                            1. re: cowboyardee

                                                                                                                              "But I'm wondering exactly what you use to sharpen with, since that might also affect how likely it is that you pull carbides out of the edge rather than sharpening them down. I've heard that oilstones and arkansas stones can be a bit more likely to exacerbate this problem than waterstones since the abrading surface doesn't grind away (unlike waterstones) and a hard grain of carbide is more likely to get 'caught' and torn out."

                                                                                                                              Shuns are real fussy about any machine sharpening, Globals less so but still require a deft touch.

                                                                                                                              I have seen what Nigelex is talking about but just on Shuns not Globals. Shuns are not on my suggested buy list of knives.

                                                                                                                              1. re: knifesavers

                                                                                                                                Hi Jim

                                                                                                                                Generally, harder and more chip-prone knives are problematic for machine sharpening. And shuns are moderately hard, but definitely a little prone to microchipping. So that's not too surprising. Globals, IME, are a little tough to sharpen compared to other knives of similar hardness, but I always figured that to be mainly related to their high wear resistance and the convex factory edge.

                                                                                                                                As I think you know, I work 98% by hand and only bust out a belt sander for major repairs - sometimes not even then. Even when I do use one, most of the actual sharpening is still done on stones. Of course, I don't sharpen nearly the volume of knives you probably do. I would expect that machine sharpening also exacerbates tear-out issues, since you have both higher speeds and abrasive particles that are relatively 'set' in place.

                                                                                                                                A few questions:

                                                                                                                                - I assume we're talking about shun classics and other shuns in vg 10, not their powdered metal lines, etc. Right?

                                                                                                                                - Do you experience the same thing whether or not you're sharpening by hand or machine?

                                                                                                                                - Do you agree with nigelx that you're seeing air bubbles, and not just losing chunks from torn out carbides?

                                                                                                                                - Have you seen the same thing happen in other knives made of vg10 - maybe tojiro DP or hattoris? I've also sharpened these knives a number of times without seeing much tear-out/holes/whatever, so I'm wondering.

                                                                                                                                1. re: cowboyardee

                                                                                                                                  "- I assume we're talking about shun classics and other shuns in vg 10, not their powdered metal lines, etc. Right?"

                                                                                                                                  Right Shuns have put me off VG-10 but I have seen carbide tear out in the older ones that are MV also.

                                                                                                                                  - Do you experience the same thing whether or not you're sharpening by hand or machine?

                                                                                                                                  Anytime I get carbide tear out I'll go old school and move to stones. I don't get many folks that are willing to pay the upcharge for the waterstone work so I have a different approach to do Shuns on machine. I can't spend 1/2 hour doing a blade on stones for $6.

                                                                                                                                  - Do you agree with nigelx that you're seeing air bubbles, and not just losing chunks from torn out carbides?

                                                                                                                                  Some of these "pits" I see are on incoming blades and are away from the cutting edge or they appear far back when sharpened, so I'm less inclined to think it is carbide pullout. I often have people send them to Shun and make a warranty claim on them but if they reject it, to bring it back and I'll do what I can.

                                                                                                                                  - Have you seen the same thing happen in other knives made of vg10 - maybe tojiro DP or hattoris? I've also sharpened these knives a number of times without seeing much tear-out/holes/whatever, so I'm wondering.

                                                                                                                                  I haven't seen enough of either to judge but nothing springs to mind. The one Hattori I recall doing made me really want one.

                                                                                                                                  I don't mind Globals and would rather see them all day long over Shun. I do have specific belts that make quick work of Globals.

                                                                                                                                  Jim

                                                                                                                                  1. re: knifesavers

                                                                                                                                    <I don't get many folks that are willing to pay the upcharge for the waterstone work>

                                                                                                                                    Just curious, what are the price differences? 3 folds?

                                                                                                                                    <The one Hattori I recall doing made me really want one.>

                                                                                                                                    Good to hear.

                                                                                                                                    1. re: Chemicalkinetics

                                                                                                                                      Basically 3 fold at $15. If heavily damaged it is more.

                                                                                                                                      I like the Hattori feel but last week did an SG-2 birchwood Miyabi like this one

                                                                                                                                      http://www.knifemerchant.com/product....

                                                                                                                                      Damn that thing was sweet. Came in real dull and easily took an amazing edge. Far easier to sharpen than a Shun for me.

                                                                                                                                      Several of these "microcarbide" Zwillings have passed through and all smoked VG-10

                                                                                                                                      Jim

                                                                                                                                      1. re: knifesavers

                                                                                                                                        I bought my friend a Miyabi Artisan. It does look nice. (no, it is not bitchwood, but close)

                                                                                                                                        http://www.surlatable.com/product/PRO...

                                                                                                                                        <Far easier to sharpen than a Shun for me.>

                                                                                                                                        Interesting because SG-2 is a harder knife. I always worry that my friend may have a tough time to sharpen this knife, but I may worry too much.

                                                                                                                                        1. re: Chemicalkinetics

                                                                                                                                          Well the SG-2 is not chippy like SG-10 so that played a huge factor.

                                                                                                                                          I do most stuff on a belt sander and carry about 30+ belts for many combinations for different blades and situations.

                                                                                                                                          Massive repairs I'll go to 24 grit and super fine I have felt with rouge.

                                                                                                                                          Jim

                                                                                                                            2. re: nigelx

                                                                                                                              That is a damning indictment for any brand if their knife has air bubbles trapped in the metal. Similarly, large carbides being present in metal is also an indicator of poor manufacture.