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Care of carbon steel knife--patina question

t
tduprey Apr 16, 2012 03:37 PM

I am a professional cook, and just made the switch from stainless to carbon. The carbon steel knife I got was made custom for me, so I really want to take the best care of it possible.

My question is this--is there any way to keep a patina off of the knife? Now, before I get the inevitable response, I know that the patina is natural and protects the knife from rust, and that it doesn't really affect the food it is cutting. I'm not worried about rust because I plan on being very attentive about keeping it dry. I know the patina is natural, and I'm ok with that, but does anybody know of anyway to just keep it looking like it did before it cut anything?

  1. cowboyardee Apr 16, 2012 04:15 PM

    For one, if it develops patina, you can always just polish the knife to remove it.

    As to whether you can keep it entirely patina-free: the answer is probably somewhere between 'it depends' and 'no.'

    Some carbon knives form a patina much more quickly and readily than others, and this will make a big difference in terms of how long you can keep the knife shiny. Perhaps with a lot of diligence and the right knife you can keep the patina away indefinitely. But IME, pretty much any carbon steel knife will form a patina given enough time and use, even if you're very careful in how you use it.

    If you want to minimize patina formation, the biggest things you can do are:
    - avoid cutting acidic foods, especially without frequently wiping the blade
    - wipe your knife frequently during use (pros I've seen working with carbon knives sometimes make it an instinctual habit to give it a quick wipe with a towel every few cuts - dice an onion, wipe the blade in one quick stroke, dice another onion)
    - wash and dry the knife immediately after use
    - maybe even give it a little coat of mineral oil before storing it.

    BTW, which carbon knives are we talking about here?

    3 Replies
    1. re: cowboyardee
      t
      tduprey Apr 16, 2012 04:39 PM

      The knife was made by Dave Schott (www.schottknives.com). He doesn't normally do kitchen knives, but the one he made turned out beautifully.

      By "polishing" what are we talking about? Using some sort of cleaning product I can buy?

      1. re: tduprey
        cowboyardee Apr 16, 2012 04:59 PM

        For removing light patina from a knife as it's forming, you can remove it with barkeepers friend. Or Flitz polish. Or most metal polishing compounds. Or stropping compound on cloth. The finer the polishing compound, the slower it will work but the shinier the knife will be. Flitz and BKF aren't really abrasive, so they shouldn't change the scratch pattern on the knife.

        For older, vintage knives with years or decades of built up patina, 3m wet/dry sandpaper would probably be necessary.

        Dave Schott looks like he's got some nice looking handiwork there, so I can see why you'd want to preserve it.

        1. re: cowboyardee
          Chemicalkinetics Apr 16, 2012 05:46 PM

          What about putting a layer of lacquer on the kitchen knife? It probably won't help the very cutting edge, but the rest of the knife should be patina/rust free.

    2. petek Apr 16, 2012 05:40 PM

      "I am a professional cook, and just made the switch from stainless to carbon'

      I've done the exact opposite,switched from carbon to SS/semi stainless.. :D
      Get ready to be very,very diligent about wiping and drying you knife often,and I mean often!(i got tired of it,but that's just me)
      Cowboy is right about different carbon knives forming a patina faster then others)I personally didn't like the patina on my Aogami #2,so I would polish it off on my highest grit stone(6k) but it would just start all over again..
      Some people like a nice natural patina,some don't..YMMV
      Post some pics of you new knife please.

      1 Reply
      1. re: petek
        cowboyardee Apr 16, 2012 05:47 PM

        I certainly wouldn't mind seeing a pic either.

      2. j
        JavaBean Apr 16, 2012 06:13 PM

        Hi, bar keepers friend, or metal polishing compounds like flitz or mag wheel polish will preserve a shiny blade finish, and remove any patina, but doesn't help prevent rust or reactive ness to acidic foods.

        Japanese chef's use baking soda and a daikon radish ( a wine cork works too) to maintain traditional knives. It works. Supposedly, the blade will eventually take on a satin or misty grey finish and will be less rust prone and reactive overtime.

        14 Replies
        1. re: JavaBean
          petek Apr 16, 2012 06:23 PM

          Japanese chef's use baking soda and a daikon radish ( a wine cork works too)

          I've seen Chef Nobu do this(on Martha Stewart show)

          1. re: petek
            Chemicalkinetics Apr 16, 2012 06:46 PM

            Me too.

            1. re: Chemicalkinetics
              d
              Dave5440 Apr 16, 2012 07:21 PM

              Me three

              1. re: Chemicalkinetics
                j
                JavaBean Apr 16, 2012 07:45 PM

                A local sushi chef told me about it. I’ve had good results doing it to higher carbon knives. On more rust or reactive steels, I prefer a patina b/c it forms a protection layer more quickly.

                1. re: JavaBean
                  Chemicalkinetics Apr 16, 2012 07:58 PM

                  Sounds like a great routine. I will give this a try too. Report in a few months. :P

            2. re: JavaBean
              kaleokahu Apr 16, 2012 07:21 PM

              Hi, JavaBean:

              WADR, I think that Flitz (and Simichrome, etc.) actually has a rust-inhibitory effect. The resulting polish is so bright and clean nothing seems to stick to it. I don't mirror my own knives, so I'm using my experience with pans as instruction--both copper and aluminum pans finished with Flitz seem to take a *lot* longer to start visibly oxidizing.

              Aloha,
              Kaleo

              1. re: kaleokahu
                d
                Dave5440 Apr 16, 2012 07:29 PM

                FLITZ™ Cleans, Polishes, Deoxidizes and Protects (For Up To 6 Months): Brass, Copper, Bronze, Sterling, Silver, Solid Gold, Pewter, Chrome, Stainless Steel, Aluminum, Beryllium, Magnesium, Nickel, Platinum, Anodized Aluminum, Armatel, Factory Hot Gun Bluing, Fiberglass, Plexiglas, Acrylic, Painted Surfaces.

                1. re: kaleokahu
                  j
                  JavaBean Apr 17, 2012 07:52 AM

                  You maybe right. I mostly use it like a spot cleaner and haven't noticed those areas being more or less rust resistant.

                  1. re: JavaBean
                    kaleokahu Apr 17, 2012 10:35 AM

                    Hey JavaBean:

                    Try it on a little bigger area. Buff out with a microfiber cloth, and then run some tap water across the piece. I think you'll see what I mean.

                    Cheers,
                    Kaleo

                    1. re: kaleokahu
                      m
                      mikie Apr 18, 2012 06:44 AM

                      Hi Kaleo,

                      For almost the entire time I've been in the plastics industry we have used Semichrome on mold steel (typically A-2 or D-2) to polish them before setting them aside for short periods of time, say a few weeks. This prevents rust and provides a smoth surface for molding. We also use Semichrome to remove mold staining which occurs as the gasses excape from the mold cavity, so it cleans and polishes and protects all in one application.

                      One other thought on protecting the steel would be to use pure carnuba wax. Carnuba is a relatively hard wax and is a common component in auto wax, Mother's sells a carnuba car wax that I believe is pure (no abrasive cleaners, but probably a solvent to make it soft enough to apply), I use it on cast iron tool surfaces, such as the table of my table saw and band saw, to prevent rust from the moisture in the air. It will not prevent rust if water is left on the surface however.

                      1. re: kaleokahu
                        j
                        JavaBean Apr 18, 2012 09:05 AM

                        Hey Kaleo. I tried it last night and could see what you mean. Like you said it's like rain-x for metal.

                        1. re: JavaBean
                          kaleokahu Apr 18, 2012 11:04 AM

                          Hi, JavaBean:

                          Glad you like it. Buy it in the big can and you'll save a bunch of $.

                          Aloha,
                          Kaleo

                    2. re: kaleokahu
                      sherrib Apr 18, 2012 02:38 PM

                      Hi Kaleo,

                      "both copper and aluminum pans finished with Flitz seem to take a *lot* longer to start visibly oxidizing."

                      I've been pretty much leaving my copper pots alone to turn whatever funky shade they want. I've been finding that even if I use BKF on them, they'll turn a rainbow of colors the minute I put them in the oven, which is why I've given up on polishing them. Will Flitz help with that? Also, what do you mean by "finished"? What do you use before using Flitz?

                      1. re: sherrib
                        kaleokahu Apr 18, 2012 08:05 PM

                        Hi, sherrib:

                        No, Flitz will not help (at least for long) with the discoloration from the oven. But my experience is that it does help a polish job last longer on the stovetop. It's the pans that get pulled out less frequently (for me, e.g., roasters, bain-maries, poachers, stockers, doufeu) that seem to hold their shine for months with Flitz.

                        Re: "finishing"... If you haven't used it already, it's hard to explain, but Flitz is a far better polish than a cleaner. If there is a lot of tarnish or any grease, the Flitz turns instantly black and you have to remove that black sludge before you can get a shine. Now Flitz *will* work as a 1-step cleaner/polish, but you have to work in one really small area at a time. I find it far less tedious to start with an acid-based product like EasyOff or a caustic base like NaOH to thoroughly degrease and knock the tarnish back a bit, and *then* hit the clean copper with Flitz. But I think any "dip and rinse" product would work for the first step.

                        There is a Brit who sells a mysterious (yet inexpensive) yellow powder on eBay, and this powder works quite well as a quick, 1-step method. It won't mirror the finish like Flitz or pink jewelers' rouge, but it is easy and fast. I'm still evaluating it. If you're interested, I'll get you a link or contact.

                        Hope this helps.

                        Aloha,
                        Kaleo

                  2. kaleokahu Apr 16, 2012 06:16 PM

                    Hi, tduprey:

                    I'd like to second the recommendation for Flitz, which seems to micropolish to a degree that water and other liquids bead on the surface. Flitz is to metals what Rain-X is to automotive and aircraft glass.

                    However, I think you've set yourself at a Sisyphean task--you'll be spending valuable time making the blade look like it's something it's not--new--and against its nature to be. One thing you might consider is that a managed patina oftentimes looks more uniform, whereas the least little blemish spot in your careful polish job is going to be glaring. Personally, I'd find an abrasive grit that works to your aesthetic, and perfect a 5-minute management routine. Polishing to newness is a mental condition akin to sharpening to perfection. Beware.

                    Hope this helps.

                    Aloha,
                    Kaleo

                    1 Reply
                    1. re: kaleokahu
                      s
                      smkit Apr 16, 2012 07:51 PM

                      I agree with Kaleo on this. Before going down that route I would try forcing a more even patina that you can live with. Also, I have often used the BKF and cork on my knives and it sort of works. It removes the big stuff, but ate awhile it just sort of gets cloudy and dull.

                      Btw, what type of carbon steel is it? Maybe I missed it up thread. I'd also try the carbon blade on some food like apples and see how they taste. Some carbon imparts not-to-pleasant taste to the food, and a patina helps reduce that. It may be that you need a patina. I have a couple of knives like that.

                    2. t
                      tduprey Apr 17, 2012 07:01 AM

                      As requested.

                      Also, I'm interested in this idea of a managed patina. How would I do that? And, maybe more importantly, what exactly is it?

                       
                      42 Replies
                      1. re: tduprey
                        k
                        kengk Apr 17, 2012 07:13 AM

                        Is it laminated? Polishing it will remove much of that effect.

                        1. re: tduprey
                          cowboyardee Apr 17, 2012 07:22 AM

                          She's a beauty. Can't tell without a closer pic, but it looks kind of like it has a patina already.

                          As managed patinas go....
                          I tend to view patina on a knife as not only functional (protective against rust, keeps the knife from reacting with foods) but also very attractive. It gives a knife character. You can let a knife develop its patina naturally, by simply cutting foods and wiping the blade - taking care to avoid rust - and letting a patina slowly set in. All you'd have to do is treat the knife well and decide not to remove the patina.

                          Others like to force a patina, using acids (vinegar, mustard, various non-food acids) meat (often raw beef or beef fat) blood or other substances to create an attractive pattern. This kind of patina can be very attractive and elaborate, but tends to lose contrast over time.

                          Others still like to force a mild patina on a new knife to give it some protection against rust, etc, and then slowly let that patina develop over time.

                          In any case, you can remove some or all of that patina at any time as you see fit. Whatever keeps your knife looking the way you like it best.

                          Here is one of my favorite threads from another forum. Lots of great looking pics of various forced and natural patinas on carbon blades:
                          http://www.kitchenknifeforums.com/sho...

                          1. re: tduprey
                            kaleokahu Apr 17, 2012 07:23 AM

                            Hi, tduprey:

                            That's a pretty knife. I like the bolster. Is it laminated steel, and what alloys? If it's a temper line, there's an old trick for bringing out even more contrast. Is the burl handle stabilized?

                            By 'managed patina', I meant just to knock it back to where you want it, but short of taking it all off. A Scotchbrite pad and scouring powder are all many people use.

                            Aloha,
                            Kaleo

                            1. re: kaleokahu
                              t
                              tduprey Apr 17, 2012 09:43 AM

                              The knife itself is 1095 high carbon steel that has been differentially heat treated. Handle is stabilized maple burl. Bolster is 416 stainless.

                              1. re: tduprey
                                kaleokahu Apr 17, 2012 10:30 AM

                                Hi, tduprey:

                                Thanks. I think 1095 makes fine knives. But it gets sniffed at by the J-knife cognoscenti.

                                So it is a temper line... The old trick is to go to Radio Shack and buy a bottle of their circuit board etch solution. You dilute it 1:1 with water (gloves and glasses and long sleeves, please). Brush it on with a chip brush and leave 1-2 minutes. Then wash off real well--a base rinse is good, too. In addition to bringing out the contrast between the quenched and non-, this will impart a finish/patina that looks a lot like the finer grades of ceramic beadblasting. I wouldn't do this until you're ready to part with the mirror finish, but until then, the acid in your own skin oil is enough to start etching bare 1095 and driving you crazy.

                                Another little-known fact: all woods I've had stabilized are still quite porous--the resin does not fill the cell structure. While it will resist warping and cracking, it can also hold moisture against the tang where the glue-up is thin. As long as you're taking care of your custom, I'd carnauba wax at least the handle and bolster, maybe the blade as well.

                                Do you mind revealing what your knife cost you? And what Dave Schott specializes in? We don't get many reviews of true customs here, and many assume that they're always very pricey.

                                Aloha,
                                Kaleo

                                1. re: kaleokahu
                                  cowboyardee Apr 17, 2012 12:45 PM

                                  To be fair to Japanese knife enthusiasts here and elsewhere, I really haven't heard that much in the way of 1095 bashing. It's not much different from the shirogami (hitachi white) steel that many J knives use, including my go-to chef knife. Instead, I think J knife enthusiasts just don't spend much time raving about 1095 simply because Japanese makers don't generally make knives in that steel.

                                  1. re: cowboyardee
                                    kaleokahu Apr 17, 2012 01:16 PM

                                    Hi, cowboyardee:

                                    OK, no disparagement intended, at all. The logic is inescapable: Since J-knife enthusiasts aren't presented with market choices that include venerable steels like 1095, D2, L6, 52100, 5160 etc., they just tend not to be enthusiastic about them. If it's not some "modern" proprietary steel used in current production, it must be inferior, is the tempting (and incorrect) implication.

                                    And it's not an issue confined to J-knives, either. All the big cutlery houses and many, many custom makers feel the inexorable tug to use modern esoteric alloys. I submit that these have worked little--if any--practical improvement in the state of the cutler's art. But it would be unwise from a marketing perspective to be caught working in the past, using steel that isn't the most "modern". Knife buyers want to believe that the steel in their blades is the best, and it's a hard sell to convince them that fantastic knives can be made out of things like railcar coil springs.

                                    Thankfully there are still makers like Schott and Kramer and others, and the ABS to give the marketeers a reality check occasionally.

                                    Best,
                                    Kaleo

                                    1. re: cowboyardee
                                      s
                                      smkit Apr 17, 2012 01:29 PM

                                      +1 to what cowboy said. I can't remember hearing anyone take on 1095 recently in the knife forums. Sometimes if a knife is made out of 1095 and it is really expensive, people might question the 'value' of the knife and label 1095 as 'simple' (Read: Cut Brooklyn). With that said, 1095 definitely isn't in the 'popular crowd' these days with custom kitchen knife makers. It seems W2, O1, and 52100 are the favored carbon steels right now.

                                      1. re: smkit
                                        Chemicalkinetics Apr 17, 2012 01:40 PM

                                        <Read: Cut Brooklyn>

                                        Are you talking to me? Are you talking to me?

                                        1. re: Chemicalkinetics
                                          s
                                          smkit Apr 17, 2012 02:43 PM

                                          No, why? Am I missing something. I was thinking about this thread from KKF.

                                          http://www.kitchenknifeforums.com/sho...

                                          1. re: smkit
                                            Chemicalkinetics Apr 17, 2012 02:48 PM

                                            :) Well, I have mentioned something along this line. In addition, I was trying to get that De Niro infamous phrase:

                                            http://en.wikipedia.org/wiki/You_talk...

                                            But apparently, he did not say "Are you talking to me?"

                                        2. re: smkit
                                          kaleokahu Apr 17, 2012 03:18 PM

                                          Hi, smkit: "Sometimes if a knife is made out of 1095 and it is really expensive, people might question the 'value' of the knife and label 1095 as 'simple' "

                                          Pretty good restatement of my point. Few people have hands-on experience with custom blades that are made and heat-treated properly. What they think they know they read about before buying (e.g., "Aogami white paper #3 extra-special", VG-10), they get what the maker sends them, and then they have *that* on which to base their hands-on experience. Good steels, like 1095 just get "forgotten". This happened with 52100, first popularized several decades ago in the highly idiosyncratic field knives of Ed Fowler, and then "discovered" anew in Bob Kramer's commercial juggernaught.

                                          This is heresy, I know, but basically all toolsteels, shaped and heat-treated properly, make good knives.

                                          Oh, and you are right, no one has slammed 1095 in particular, it just gets no love when IMO it (and many other steels) should.

                                          Aloha,
                                          Kaleo

                                          1. re: kaleokahu
                                            s
                                            smkit Apr 17, 2012 07:13 PM

                                            Very much agree Kaleo. It is strange how steels become popular (and not so popular) and 1095 will hopefully have its day again. I remember when Devin Thomas and his son, Larrin, stood by AEB-L at KnifeForums for a long time before people started accepting that steel for knives. Now it has become quite popular. 1095 just needs a 'booster' to stand by it once again (in the kitchen), make great knives with it, and interact with the knife community. Unfortunately, the knives of Joel Bukiewicz (of Cut Brooklyn) don't break out of the NYC locale much. He doesn't care to interact with the forums really and one time I wrote him AND called him to buy one of his knives and never got a response. I respect him, still want one of his knives, but he doesn't seem to need knife knuts and forums. He makes his coin in other ways.

                                            1. re: kaleokahu
                                              s
                                              shezmu Apr 17, 2012 09:36 PM

                                              I didn't know you were a knife dude, kaleo.

                                              1. re: shezmu
                                                kaleokahu Apr 18, 2012 06:40 AM

                                                Hi, shezmu:

                                                There was a time when I made quite a few. It's a tough way to make a living.

                                                Aloha,
                                                Kaleo

                                                1. re: kaleokahu
                                                  s
                                                  shezmu Apr 20, 2012 11:43 AM

                                                  I hear you on that. I seen people make knives before and yeah, definitely not something you do if you don't love doing it.

                                        3. re: kaleokahu
                                          t
                                          tduprey Apr 17, 2012 02:56 PM

                                          So, force the patina with the circuit board etch? With the mustard/vinegar/lemon/chicken ideas? Or naturally? Or just continually use BKF/baking soda-daikon?

                                          Also, to open up an entirely different and I'm sure more heated debate--steel it or just super fine grade it?

                                          So far, the knife is wonderful. I was lucky enough to work with Dave throughout the entire process, which was great because the balance point, weight, etc, are just where I want them. I'll let you all know how it stands up over time. As far as price, it was a gift so I'm not totally sure, but I think around $500.

                                          1. re: tduprey
                                            Chemicalkinetics Apr 17, 2012 03:37 PM

                                            <So, force the patina with the circuit board etch? With the mustard/vinegar/lemon/chicken ideas? Or naturally? Or just continually use BKF/baking soda-daikon?>

                                            Really whatever you like. You can try all of them and see which works best for you, and frankly that is what most people do.

                                            I like my patina forms naturally from using the knives, but you just have to give these methods a try.

                                            1. re: Chemicalkinetics
                                              petek Apr 17, 2012 05:40 PM

                                              "I like my patina forms naturally from using the knives"

                                              Speaking of patinas(and slightly OT),when are you going to give us a review of your Moritaka honesuki?? How are you liking it,or not?

                                              1. re: petek
                                                Chemicalkinetics Apr 17, 2012 05:44 PM

                                                Petek,

                                                There is a very good reason why I have not reviewed this beautiful knife. :)

                                                I have not used it yet.

                                                I have finally finished all the chicken from the freezer and bought a chicken today. It is almost as if you knew I just bought a chicken. I will debone it either tonight or tomorrow.

                                                I have sharpened it, and this thing can really take on a great edge, so this is a good thing because I wasn't super impressed with the factory edge.

                                                1. re: Chemicalkinetics
                                                  petek Apr 17, 2012 06:06 PM

                                                  "I will debone it either tonight or tomorrow."

                                                  don't forget,it's not only for deboning chickens..works great on all sorts of proteins(lamb,beef,pork etc)
                                                  hurry up and use it will ya!! :D

                                                  1. re: petek
                                                    Chemicalkinetics Apr 18, 2012 10:00 PM

                                                    Petek,

                                                    Just a quick note. As you know, I wasn't completely convinced in the beginning which was why honeski was fairly low on my list for purchase.

                                                    I just used the Moritaka honesuki, and it is pretty cool. Obviously, I have to use it a few more time to be sure, but I can already see some advantageous of the honeski design over the traditional (Western) boning knife. For one, I can effortlessly cut through the joint. Removal of skin now requires a much lighter touch than before, or else I would just cut through the skin because the much sharper edge. So this is probably a disadvantage for now, but it is certainly something I can adjust overtime.

                                                    One last thing, the Moritaka Aogami Super edge certainly holds up well. I didn't cut any hard bones, but I have definitely cut through a few soft bones, joints...etc. Without any touchs-up, I tested its edge against a paper. It has no problem push-cutting the paper throughout the entire length of the edge.

                                                    I will probably write up a short review in a day or two. Thanks.

                                                    1. re: Chemicalkinetics
                                                      petek Apr 19, 2012 02:55 PM

                                                      <I will probably write up a short review in a day or two. Thanks>

                                                      Looking forward to it doctore!

                                                      The fact that you're a home cook,I'm actually surprised you bought such a specialised/task specific knife(not that there's anything wrong with that).The more you use her,the more you'll like her..

                                                      1. re: petek
                                                        Chemicalkinetics Apr 19, 2012 03:13 PM

                                                        <,I'm actually surprised you bought such a specialised/task specific knife(not that there's anything wrong with that).>

                                                        ?!?!? Were you not the one who kept pushing me to buy it? :P

                                                        It is like you set me up for a date and then ask me why did I went out with her. :P

                                                        No, really.... a honesuki was very low on my list until a bunch of you guys told me to move it up on my purchase list. I think I was looking to get another santoku or a Elephant**** craving knife.

                                                        1. re: Chemicalkinetics
                                                          petek Apr 19, 2012 05:32 PM

                                                          <?!?!? Were you not the one who kept pushing me to buy it? :P

                                                          It is like you set me up for a date and then ask me why did I went out with her. :P>

                                                          I didn't realize how influential I was..... :-D

                                                          1. re: petek
                                                            Chemicalkinetics Apr 19, 2012 07:40 PM

                                                            <I didn't realize how influential I was..... :-D>

                                                            Like I have suggested, I would go out with any lady based on your recommendation. :P

                                                      2. re: Chemicalkinetics
                                                        scubadoo97 Apr 19, 2012 05:12 PM

                                                        I've boned out and spatchcocked many chickens and still find that my Tojiro HD honesuki can slide through paper without touch ups. No nicks when view with magnification. I do sharpen it but only rarely compared to my other knives. I think it's the near chisel edge of the honesuki.

                                                        1. re: scubadoo97
                                                          Chemicalkinetics Apr 19, 2012 05:52 PM

                                                          <my Tojiro HD honesuki>

                                                          Just curious. Was it a Tojiro DP honesuki or was it a Hattori HD?

                                                          <No nicks when view with magnification>

                                                          I didn't notice any nicks on mine either, but I didn't use a magnifying glass.

                                                          1. re: Chemicalkinetics
                                                            scubadoo97 Apr 19, 2012 08:01 PM

                                                            DP.

                                                            Not enough sleep and typing on this little screen

                                                            1. re: scubadoo97
                                                              Chemicalkinetics Apr 19, 2012 08:05 PM

                                                              By the way, I just want to clarify that I don't think my Moritaka honesuki has a 90/10 or even 80/20 bevel edge. I think it was closer to 50/50.

                                                              <Not enough sleep and typing on this little screen>

                                                              No typing on a small screen... you will get near-sighted :P

                                                    2. re: Chemicalkinetics
                                                      scubadoo97 Apr 18, 2012 03:55 AM

                                                      The 90/10 or so edge is really easy to sharpen. Will also be interested in your assessment compared to more traditional boning knives

                                              2. re: kaleokahu
                                                petek Apr 18, 2012 11:17 AM

                                                kaleo

                                                "the J-knife cognoscenti"

                                                So which is it? The J-knife cognoscenti or the J-knife mafia? :-D

                                                One suggests knowledge and expertise..the other extortion and racketeering..

                                                1. re: petek
                                                  kaleokahu Apr 18, 2012 12:09 PM

                                                  Hi, Pete:

                                                  I think both are useful. Knowledge and expertise for sure with cognoscenti, but to me 'mafia' also connotes insularity and clubbiness, maybe even secret languages and rituals. Less on extortion and rackets.

                                                  Maybe it should be J-knife Yakuza? Hmmm... maybe that's how it all began...a pinch grip gone terribly awry...yes...the pinky curls under, and...off it goes at the first joint, push-cut of course!

                                                  Aloha,
                                                  Kaleo

                                                  1. re: kaleokahu
                                                    petek Apr 18, 2012 02:39 PM

                                                    Ha! :-D

                                                    1. re: kaleokahu
                                                      cowboyardee Apr 18, 2012 04:49 PM

                                                      "a pinch grip gone terribly awry...yes...the pinky curls under, and...off it goes at the first joint, push-cut of course!"
                                                      _____
                                                      How you know you're way too into Japanese knives: you accidentally cut a finger off and your first thought is: "dammit, I hope I didn't chip the blade on the bone"

                                                      1. re: cowboyardee
                                                        s
                                                        smkit Apr 19, 2012 02:54 PM

                                                        "How you know you're way too into Japanese knives: you accidentally cut a finger off and your first thought is: "dammit, I hope I didn't chip the blade on the bone"

                                                        ________

                                                        ...and then which do you do first: bandage your finger or wipe the blade down?

                                                        1. re: smkit
                                                          scubadoo97 Apr 19, 2012 02:57 PM

                                                          Well I'm not that much of a freak. Wipe down the blade first then look for the finger.

                                                          1. re: smkit
                                                            Chemicalkinetics Apr 19, 2012 03:14 PM

                                                            Ha ha ha. I don't think this applies just to Japanese knives though.

                                                            1. re: smkit
                                                              cowboyardee Apr 19, 2012 08:10 PM

                                                              Neither really. The blood can leave a sweet little patina pattern on the blade, so first up I might dab a bit of mustard on in spots for contrast. I'd go to the ER once the patina set, of course.

                                                              1. re: cowboyardee
                                                                Chemicalkinetics Apr 19, 2012 08:16 PM

                                                                This only makes sense if it is a carbon steel knife.... What if it is a stainless steel knife?

                                                2. re: tduprey
                                                  j
                                                  JavaBean Apr 17, 2012 07:41 AM

                                                  Here's a good how to force a patina link.
                                                  http://darkhoek.blogspot.com/2011/01/...

                                                  1. re: tduprey
                                                    petek Apr 17, 2012 09:15 AM

                                                    As requested.

                                                    Sweet!

                                                  2. k
                                                    kengk Apr 17, 2012 02:53 PM

                                                    I would be interested in the thought process that led to using 1095 instead of something like O-1. I wouldn't think the cost difference would be of any real consequence when weighed against the price of a custom knife.

                                                    Not that I don't think the 1095 will make a fine knife.

                                                    5 Replies
                                                    1. re: kengk
                                                      d
                                                      Dave5440 Apr 17, 2012 07:02 PM

                                                      1095 and O1 are vitually identical, except O1 has tungsten(,6%) and chromium(.6%) in it , which increases wear resistance and carbide formation.
                                                      Cost would not be an issue, both are cheap, I bought a piece of O1 big enough to make 4 knives for 60$

                                                      Here is a good chart for quick reference, and his site is loaded with all things knife

                                                      http://zknives.com/knives/steels/stee...

                                                      1. re: kengk
                                                        kaleokahu Apr 17, 2012 07:11 PM

                                                        Hi, kengk:

                                                        Perhaps Schott has his own and different reasons, but the OP's blade was differentially heat-treated. If you're going to this effort, it's nice to have a temper line or hamon to show for it. O-1 tends not to show them. The 10-series steels do.

                                                        Aloha,
                                                        Kaleo

                                                        1. re: kaleokahu
                                                          d
                                                          Dave5440 Apr 17, 2012 08:21 PM

                                                          OP's blade was differentially heat-treated. If you're going to this effort,

                                                          Really ? This effort? Instead of "drop" lower "slowly" in the quench agent, same way i was taught in trade school to do do punches and chisels 27yrs ago but you keep thinking it's something new

                                                          1. re: Dave5440
                                                            kaleokahu Apr 18, 2012 07:17 AM

                                                            Hey, Dave5440:

                                                            Effort... I meant that a couple of different ways. First, however easy it may be to quench, most kitchen knives don't need to be differentially treated. But buyers like the hamon, ask for it, so whatever is done to put one in the blade--cleanly and distinctly--takes some effort. If they ask and pay for it, you give it to them, but they can't *see* it, it doesn't take a Zen master to know it isn't really there when it comes to business.

                                                            Second, if the bade has any belly or rocker to it at all, the "lower slowly" method becomes problematic (and defeats the purpose of having an edge of uniform known hardness). Getting a very shallow dual-depth quench set up, right temperature, the depth of the hamon and rocking the hot blank, edge down, tapering line to the very tip, IMO takes effort. I made a fancy, thick ulu blade one time (the blank started as a 5" circle of 52100) and to get the HT right with a temper line, I had to get Kramer to help me do it.

                                                            I'm sorry, I don't know where you got the idea I think differential HT is new. It *is* uncommon (and largely superfluous) in kitchen knives. But when people see a knife with a line and understand what it's supposed to mean, they want it--as witnessed by the idiocy of makers laser-etching fake ones on kitchen knives. Sometimes custom makers just want to put the dog on, show off a little (e.g., a 5-inch diameter ulu that doesn't need soft above the hamon!)

                                                            Aloha,
                                                            Kaleo

                                                            1. re: kaleokahu
                                                              d
                                                              Dave5440 Apr 18, 2012 09:00 AM

                                                              But when people see a knife with a line and understand what it's supposed to mean, they want it--as witnessed by the idiocy of makers laser-etching fake ones on kitchen knives

                                                              Very good point Kal, as is most of the others

                                                      2. d
                                                        DSchott Apr 24, 2012 01:13 PM

                                                        Hello,
                                                        My name is David Schott and I made this knife so I thought I'd quickly chime in on a few points that have been brought up. 1095 was chosen as the steel here because the desired knife was to have a visible hamon produced by differential heat treating processes. A steel like 01 is nearly air-hardending and as a result produces a poor hamon, if any. Most steels other than W1, W2, 1080+ do not produce good hamons.

                                                        The pattern on the blade is a true hamon, with a perlite composition above the transition line and fully hardened steel below it. It is applied and controlled through application of satinite clay which masks the spine from quenching, which in turn causes the spine to miss its hardening window (1095 requires lowering temperatures from over 1450 degrees to below 400 in less than a second via quenching.) Lots could be said here, but its not nearly as simple as it seems..."drop slowly" is a gross misrepresentation of what it takes to properly produce a distinctive hamon.

                                                        This pattern is not visible without etching/polishing. The blade is first etched in a ferric chloride solution (the same as PCB etchant at radio chack) and then many subsequent polishing cycles.

                                                        While a hamon is largely aesthetic on a kitchen knife, its a visual representation of a human process that is not done by production companies and has intrinsic value in the custom knife world.

                                                        This blade should NOT have ferric chloride re-applied by anyone who is not a knifemaker or familiar with using it to produce visible hamons. If anything, patina should be lightly polished off the blade, not purposefully applied to the blade. The relatively polished finish should resist rust a bit more than a typical grinder-finish, but patina and aging are what make a carbon knife develop character with time.

                                                        As for using 1095, a steel is only as good as its heat treatment. I can make a horrible performing knife out of really expensive stainless supersteel or I can make a great knife out of a time-tested carbon steel. Everything is in the heat treatment...

                                                        4 Replies
                                                        1. re: DSchott
                                                          cowboyardee Apr 24, 2012 02:39 PM

                                                          Thanks for posting. Yours is a nice-looking chefs knife. Do you make kitchen knives often? Any general philosophy or leanings when making kitchen knives?

                                                          1. re: DSchott
                                                            kaleokahu Apr 24, 2012 07:12 PM

                                                            Hi, David:

                                                            Welcome, and thanks for the information. Please keep posting. We can always use more makers' input.

                                                            Aloha,
                                                            Kaleo

                                                            1. re: kaleokahu
                                                              d
                                                              DSchott Apr 25, 2012 04:02 AM

                                                              Hi!
                                                              Cowboyardee,
                                                              I don't make kitchen knives that often...in fact this was my first! I have, however, been making knives for almost ten years now. I found the most challenging thing to be the heat treatment. With such a "fast" quenching steel like 1095, warping is always a problem. Adding differential heat treating into the mix as well as a 10" and very thinly ground blade proved challenging to say the least. Design-wise kitchen knives are not overly complex compared to something like a folding knife but I had to do some research on handle designs to ensure I didn't completely miss the boat.

                                                              1. re: DSchott
                                                                Chemicalkinetics Apr 25, 2012 06:06 PM

                                                                <in fact this was my first>

                                                                Thank you.

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