Handle - Original
- I already mentioned that the handle is real big on this knife. As for the details, it's made of Magnolia with Water Buffalo horn bolster. Shape - standard D shaped handle. I, personally, like octagonal handles a lot more than the D shapes. For a while I was debating, whether or not to keep this knife, thus I didn't do anything about its handle. However, later (in Jan. 2009) I've decided that I was keeping it, and now replacing the original handle is in progress. Once the handle upgrade is completed I'll update this section, with new data and photos.Handle - Custom
- As promised, here is an update after I have received the rehandled, or one could say reborn Aritsugu A-Type. After I have decided I'd keep Aritsugu A-Type gyuto, there was few weeks long conversation with Stefan to pick the handle materials and color combinations. That part is difficult, so many choices out there, then of course, Murphy's law kicks in, and you find out that the rare spacer material you were picking for 4 weeks isn't available anymore and things like that, but eventually I've picked yellow on black design, and in my opinion it came out just gorgeous. So, in the end, the handle material ended up being African Blackwood, which is pretty much the only wood type name I can remember, other than Ebony and Ho Wood. Spacer and buttcap, originally were designed to be amber, if possible, that is if the cost and machinability allowed for it, but in the end, we opted for the artificial Amber. Came out just fine. Not as clear as some Amber I've seen, but works fine. African blackwood is dense, and obviously it is black ;) In the beginning, I was opting for the Ebony, which is considered higher grade wood, but now I prefer blackwood. For now, it's blacker than Ebony, which in fact isnt' all that black, but goes from dark brown to lighter colors. Second, getting top grade ebony is a pain, then the surface is pretty much never as smooth as that of the blackwood. Ebony is slightly denser than the blackwood, but overall, for a human being it is pretty much impossible to tell the density or weight difference when holding and using a knife. Besides, blackwood does feel really nice in hand. So, for all of my future black handles, and I do like them in black I'll be choosing blackwood.As far as the new handle goes, I just love it. In terms of dimensions, it is slightly slimmer and longer than the original one, in fact Stefan was thinking it'd be a good fit for Yanagiba, but I wanted it on A-Type, because it is quite thin and lightweight gyuto. Like I said blackwood itself feels very nice, and the new dimensions are working just fine for me. The whole knife became heavier, which is pretty obvious, as the blackwood is significantly denser than ho wood, and artificial amber spacers aren't featherlight either. If you want the specifics, then the net weight of the knife went from its original - 210.00g(7.1oz) to 244.00g(8.25oz). Well, as you can guess 34g difference isn't something that would make dramatic changes in the knife balance, which unless someone made it really wrong isn't all that important anyway. Well, I feel it's working for me alright, new handle looks gorgeous, so all is good in that department.
Steel
- The makeup of the steel that Aritsugu is using for his A-Type knives is not officially published, but referred as Gokinko. Actually, after couple years of chasing the composition of that steel, I am not even sure if A-Type isn't another name for it. Either way, thanks to KF member Rottman, now we do have gokinko steel composition. He was kind enough to send his knife for testing to the lab and the exact composition came up as following: C = 0.987%, Mn = 0.30%, Cr = 7.03%, Mo = 0.304%, W = 0.217%, V = 0.127%. It's a proiprietary steel, although somewhat close to Vascowear steel, however, later has higher amounts of Molybdenum in it. With 7% of Chromium in it, Gokinko or A-Type steel does have some degree of stain resistance. Actually it's pretty good stain resistance too. Even after cutting pineapples the patina didn't develop. There were different rumors out there, stating that it might be either D2 or D3 tool steel, and I said I didn't believe it was either one of those, based on my personal experience with D2 steel at 62HRC. Well, I am glad I was right ;) In short, very good steel for kitchen knives, except it's one of the most difficult ones to sharpen, but unless you are rebeveling the edge it is no trouble.The tricky thing is that officially, Aritsugu A-Type knives are hardened at 60-61HRC. However, they are one of the most difficult knives to sharpen. In other words, the wear resistance of this alloy is extremely high. I've sharpened several D2 knives, all the way up to 62HRC, nothing like Aritsugu blades. D2 is a lot easier to sharpen, but on the downside, dulls faster too. The usual story, high wear resistance equals very good edge holding and stability, and unfortunately, it also equals sharpening difficulties. However, the edgeholding ability of Aritsugu knives is very high and very well respected and appreciated by many, knife enthusiasts and pro chefs alike. Also, not to make things sound too gloomy, the major difficulty is to put initial bevel on the edge, that's when you have to grind significant amount of metal away, once that bevel is in place, resharpening and maintaining the edge is very easy, plus because the edge holding is very high, you don't really have to sharpen that often (disclaimer - that depends on the stuff you cut and the amount of that stuff too). One more thing to keep in mind, is that I like my knives with thin or very thin edges. That is one of the reasons why I have to spend so much time grinding. If you want 15° or even 20° edge on the front side you'll need a lot less time compared to 8°-10° or even 12°edges. Overall, it is my impression that Aritsugu is trying to get the reasonably priced knives out there with highest edge holding ability. Of course, he has fancy knives too, if you are interested. Althgouh, on the downside, customizations from Aritsugu shop are outrageously expensive.
Sharpening
- A-Type gyuto wasn't my first Aritsugu knife to sharpen. I already had experience with Aritsugu Honkasumi Yanagiba, few month prior to this gyuto. Therefore, I was well prepared (mentally) and well equipped to get this beast in shape I wanted. Especially, that this time I got two Aritsugus together, this gyuto and 270mm Fugubiki. As stated above, main problem with those knives, is to get the initial edge on them, after that it's really nothing to speak of. That is easier said that done though. I got DMT XXC 120 grit diamond stone, specially for those two knives. Well, that DMT is very useful for many things, including sharpening stone flattening, but the major reason I got it, was that I knew, I had to deal with Aritsugu knives in the near future.Long story short - I've spent around 3 hours on A-Type gyuto with DMT-XXC 120 grit stone. That's a lot of time, but there were two reasons for it, besides of the exceptionally high wear resistance of the steel. One, rather obvious is that the knife is big. 270mm(10.6") blade is no joke to deal with at any rate. Second, I was lowering the angle to 12° approx on the front side, also I've decided to give the gyuto back bevel, approximately 3°-5°. That is really low angle, considering that we're discussing single bevel knife here. Perhaps, I could've shaved few minutes by pushing the blade harder onto the stone, but diamond stones aren't designed for high pressure. Push the steel hard into it and diamond crystals start chipping out, basically you're destroying the stone by doing that. However, after those 3 hours, once I've set the initial bevel as I wanted it, everything went much faster.
First was the 700 grit Bester Japanese waterstone. That was to refine edge, and more importantly remove the deeper scratches left by DMT D8XX diamond stone. Next up, 15µm Silicon Carbide(SiC) abrasive film on the leather pad, which was followed by 5µm SiC film. At this point, the edge was already quite sharp, but I wanted the perfect edge. So, next came 2µm Chromium Oxide(CrO) abrasive film, which in turn was followed by 8000-12000 grit(~1µm) Kitayama Japanese waterstone. Final steps included: 0.5µm CrO powder loaded strop, then another leather strop, loaded with 0.25µm diamond spray, and finally just a few passes on plain leather strop, to remove leftovers of the burr. The result you can see on this photo. Mirror polished, acute edge, that is sharp as a hell's razor, if such a thing exists. Second part lasted around 45 minutes or so. As you can see, it is a lot easier if, or when you have the initial edge. On the first photo you can see both, Aritgusu GYuto and Aritsugu 270mm Fugubiki polished edges. Now, take a look at the second photo. It was taken later, but the edge has even better mirror polish, due to repeated stropping and touchups on 0.5µm and 0.25µm diamond loaded strops. Still, with ~150x magnificaiton you can see how rough the edge bevels still are. Those scratch marke were left by DMX D8XX 120 grit stone and I didnt' work longenough with Bester and other higher grit abrasives to smooth them out.
As for the maintenance, most of the time all I have to do, is just a few passes on 0.25µm diamond spray loaded leather strop, plus another dozen or so passes on a leather strop. If, or when, the knife gets duller, I'll have to go back to 5µm abrasive. However, after few months of use, that hasn't happened yet. Partly because, I have bunch of other gyutos that I use interchangeably, besides, I don't always use gyutos for all the cutting, nakiri, and chukabocho(cleaver) are often substituting gyutos for veggie cutting. Other knives have to work for me too.