Looking for recommendations for top quality HAP-40 & ZDP-189 knives

[Bret Koesser]

I've recently moved up the ladder in terms of stainless steel Japanese knives from VG-10 to SG2. I've noticed a marked difference in edge retention and even sharpness. I'm assuming a big reason is increased hardness along with significantly smaller steel grain size. As a result, I wanted to obtain a couple knives made from HAP-40 & ZDP-189 since they should be another step up from SG2. I was hoping to draw upon the collective knowledge which knife to get and where the best place to get it would be.

My current favorite knife is a SG2 Nakiri from Yu Kurosaki and saw that he had made a line of knives made from HAP-40 so I was hoping to get one of those, but they seem to be very hard to locate in stock. Also, while not specifically named ZDP-189 steel I believe that Miyabi's Black product line is made from ZDP-189. Would that be a good choice or is there a better option from a more custom bladesmith?

I'm hoping to use them to do some testing both in terms of regular kitchen duty performance as well as learning nuances around sharpening and maintaining an edge and general care. While I love using my Japanese knives, I tend to baby them and haven't had any issues with damaging them or mistreating. To me, they represent the whole fusion of my love of food, food prep, knives and knife steel. Such a cool and wonderful journey this has been.

 

[jakuda]

There is a HAP40 in the BST forum right now with a custom saya....
Magnacut is another new steel that custom knifemakers have been playing with. @MSicardCutlery on this forum does customs with magnacut as well as occasional non-custom knives on the sponsor page.

 

[Barmoley]

I've had good experience with Sukenari knives in general and their HAP-40 specifically.

 

[aporigine]

I've had good experience with Sukenari knives in general and their HAP-40 specifically.

I have a FRKZ (Sukenari rebrand) petty in ZDP. Stays sharp forever. Shaptons and Choseras work on it … slowly.

Kohetsu is another to look at for Hap40.

 

[jakuda]

I've had good experience with Sukenari knives in general and their HAP-40 specifically.

same. No problems with my Sukenari HAP40 240mm sujihiki

 

[jedy617]

+1 sukenari for Japanese pm steels

 

[Bret Koesser]

There is a HAP40 in the BST forum right now with a custom saya....
Magnacut is another new steel that custom knifemakers have been playing with. @MSicardCutlery on this forum does customs with magnacut as well as occasional non-custom knives on the sponsor page.

I was gifted a Culinary set from Montana Knife Company which uses Magnacut, but they are heat treated to 61 instead of these super hard levels that we're talking about with SG2, HAP-40, and ZDP-189. The upside to that is that those blades are super tough and do not require quite as much attention to chipping. Variety is a spice of life and I'm an equal opportunity knife user. Sometimes when I have a prep that might be kind of hard on an edge I'll use those so I don't worry about chipping an edge on my delicate Japanese blades. Magnacut isn't quite as fine grained as the two steels I'm looking to test and certainly not as hard. It probably holds an edge almost as well, but I'd like to see in practical terms rather than rely on theory.

 

[Barmoley]

I was gifted a Culinary set from Montana Knife Company which uses Magnacut, but they are heat treated to 61 instead of these super hard levels that we're talking about with SG2, HAP-40, and ZDP-189. The upside to that is that those blades are super tough and do not require quite as much attention to chipping. Variety is a spice of life and I'm an equal opportunity knife user. Sometimes when I have a prep that might be kind of hard on an edge I'll use those so I don't worry about chipping an edge on my delicate Japanese blades. Magnacut isn't quite as fine grained as the two steels I'm looking to test and certainly not as hard. It probably holds an edge almost as well, but I'd like to see in practical terms rather than rely on theory.

MagnaCut is significantly finer grained/has smaller carbides than ZDP and possibly HAP-40, it probably is. It has slightly finer carbides than 4V.

SG2 usually runs at 62-63 and I doubt you will be able to tell the difference. ZDP and HAP-40 usually run very hard, so there you could see a difference in slicing edge holding especially with ZDP. You should also see a significant difference if you loose your sharpness due to edge deformation such as rolling, denting, etc. This all assumes that your geometry is the same among steels if not you won't know if the specific steel makes any difference.

 

[Nemo]

I've recently moved up the ladder in terms of stainless steel Japanese knives from VG-10 to SG2. I've noticed a marked difference in edge retention and even sharpness. I'm assuming a big reason is increased hardness along with significantly smaller steel grain size.

At first blush, it seems surprising that you have noted a marked difference in edge retention between VG10 and SG2. Sure, there is a difference but I wouldn't have said it was marked. VG10 and SG2 are often heat treated to similar hardness. SG2 does have a finer carbide structure due to the PM process. Grain size will depend somewhat on heat treatment.

VG10 is notoriously challenging to deburr (this is said to depend quite a bit on heat treatment) and I wonder whether this discrepancy could represent incomplete deburring of your VG10 knives? @Benuser has a lot of experience deburring VG10 knives and may be able to comment further.

 

[Bret Koesser]

MagnaCut is significantly finer grained/has smaller carbides than ZDP and possibly HAP-40, it probably is. It has slightly finer carbides than 4V.

SG2 usually runs at 62-63 and I doubt you will be able to tell the difference. ZDP and HAP-40 usually run very hard, so there you could see a difference in slicing edge holding especially with ZDP. You should also see a significant difference if you loose your sharpness due to edge deformation such as rolling, denting, etc. This all assumes that your geometry is the same among steels if not you won't know if the specific steel makes any difference.

Ok, good to know on the Magnacut grain size. I don't remember where I saw info before, but I recall it saying the gain size was roughly the same as SG2. I'm certainly no expert so I always welcome more info.

 

[Bret Koesser]

At first blush, it seems surprising that you have noted a marked difference in edge retention between VG10 and SG2. Sure, there is a difference but I wouldn't have said it was marked. VG10 and SG2 are often heat treated to similar hardness. SG2 does have a finer carbide structure due to the PM process. Grain size will depend somewhat on heat treatment.

VG10 is notoriously challenging to deburr (this is said to depend quite a bit on heat treatment) and I wonder whether this discrepancy could represent incomplete deburring of your VG10 knives? @Benuser has a lot of experience deburring VG10 knives and may be able to comment further.

I guess it's hard to say without any close-up pics of the apex. Given we have no proof it remains conjecture. A remaining burr is possible, but personally I kind of doubt it. Still maybe...and maybe not. It does kind of make me want to get some camera to hook up to my computer. Also, I've been meaning to obtain a higher powered loop for edge inspection for a while just haven't done it.

As for the difference between VG-10 & SG2, maybe some of that is attributable to the blade profiles as well. They are not the same maker or necessarily even the same style of knife (ie. Gyuto, Nakiri, etc.) Either way, the edge feels very different to me both using my fingers and during cutting of product. When I say "marked" different, basically I mean that I can tell "a" difference. Since they both cut so nicely, to me, any difference I consider "marked". Maybe that helps put a context around my words and what I mean.

 

[Nemo]

I guess it's hard to say without any close-up pics of the apex. Given we have no proof it remains conjecture. A remaining burr is possible, but personally I kind of doubt it. Still maybe...and maybe not. It does kind of make me want to get some camera to hook up to my computer. Also, I've been meaning to obtain a higher powered loop for edge inspection for a while just haven't done it.

As for the difference between VG-10 & SG2, maybe some of that is attributable to the blade profiles as well. They are not the same maker or necessarily even the same style of knife (ie. Gyuto, Nakiri, etc.) Either way, the edge feels very different to me both using my fingers and during cutting of product. When I say "marked" different, basically I mean that I can tell "a" difference. Since they both cut so nicely, to me, any difference I consider "marked". Maybe that helps put a context around my words and what I mean.

Yeah, all of these things play a role and it may well be that your deburring is fine. To be clear, I'm talking about removing removing microscopic burrs that you'd need a decent (microscope-level) amount of magnification to see. My thinking was that this could be an opportunity to reflect on your deburring technique and decide whether refining it might progress your sharpening skill. I say this because in my own sharpening progress ("sharpening journey" is beginning to sound a bit cliche), paying close attention to deburring technique has unlocked significant improvements in both sharpness and edge retention, especially for difficult to deburr steels.

Anyway, I'm getting towards thread derailing territory here (and I'm actually quite interested in the original topic), so would be happy to discuss this further in a different thread if you are interested and no problem at all if you are happy with things as they stand.

On with the original topic.

 

[btbyrd]

Two of my favorite knives are Sukenari ZDP and HAP40. The edge length tends to run a bit short, so I’d advise against a 210.

 

[HumbleHomeCook]

If I was just looking to dip my toe in, didn't mind some rougher F&F so I didn't mind experimenting and wasn't sure how committed I was going to be, I'd choose one of these:

https://knifejapan.com/shop-by-steel/hap40-high-speed-steel/

Personally I'd opt for the Kawatsu nakiri.

 

[pavhav]

If you're determined to go this route, Sukenari is a reliable choice. Perhaps Gihei as well, but I haven't tried theirs. As has been said above, geometry, heat treatment, surface finish, etc., will all probably have more effect than the steel choice.
The Miyabi Black looks good, and has a hard HT, but is fairly robust behind the edge, and handle heavy; this is not necessarily bad, but worth consideration.
I have examples in all of these steels, (HAP-40, SG2, ZDP-189), and many others, (K390, ApexUltra, MagnaCut, etc.), but I can't really report a "marked difference" unless comparing something like Shirogami 2 and K390 -- the rest feels like a subtle give and take of properties which you're likely to end up valuing differently as your exploration continues.

 

[Nemo]

Only Hap40 I have used is Gihei. Fairly thin blade. Harder to sharpen well than SG2. Mainly, it's harder to properly deburr. Unless you use diamonds as your fine stone. Then, it's pretty similar to SG2. Edge retention seemed longer than similar SG2 knives. But it's not night and day.

 

[Bret Koesser]

@Barmoley I went back to Larrin Thomas' site (Knife Steel Nerds) and read an article talking about Magnacut grain size and it mentioned a number of 5.5 micron. I was unable to get a solid number for either SG2, HAP-40 or ZDP-189, but my understanding is that SG2 is something like 3-5 micron, HAP-40 & ZDP-189 are maybe 1-2 micron.

Not to be a smart a$$, but I consider a piece with Larrin's name on it as a quality source. I guess I'm wondering if you have references I can use to make sure my understanding matches reality. I'm at the stage where I'm just wanting to learn all I can as this is a topic is kind of a current obsession for me.

 

[jedy617]

@Barmoley I went back to Larrin Thomas' site (Knife Steel Nerds) and read an article talking about Magnacut grain size and it mentioned a number of 5.5 micron. I was unable to get a solid number for either SG2, HAP-40 or ZDP-189, buy my understanding is that SG2 is something like 3-5 micron, HAP-40 & ZDP-189 are maybe 1-2 micron.

Not to be a smart a$$, but I consider a piece with Larrin's name on it as a quality source. I guess I'm wondering if you have references I can use to make sure my understanding matches reality. I'm at the stage where I'm just wanting to learn all I can as this is a topic is kind of a current obsession for me.

 

[jedy617]

You can see above how magnacut is way finer. That's from knife steel nerds so not sure what you were reading

Regardless, as someone who is also really into steel, the knife itself and geometry matters way more than the steel. ZDP has super low toughness but I've never had a problem with it in the kitchen. Magnacut is gonna be the best all rounder choice for stainless though

 

[pavhav]

Are we perhaps conflating austentic "grain" size vs. carbide size? Large chromium carbides, vs. comparatively small vanadium carbides?

 

[Bret Koesser]

This is what I was reading...

 

[Bret Koesser]

@pavhav I don't know. Admittedly this is quickly getting way beyond my understanding. I'm only smart enough to pick out the quantitative number of 5.5 microns. I'm only guessing when I look at the photos, but it does look like the dots are smaller on Magnacut than ZDP-189. So now that this thread has taken off on a tangent I would like more clarification on this if ZDP & HAP are not really the smallest grain knife steels.

@jedy617 I don't know if the two articles are in conflict with each other, or even how to reconcile the information. Either way, I already have a Magnacut knife and know how it performs for me. Maybe I can save myself some money and not even bother with venturing into other knife steels.

 

[jedy617]

Just look at the picture. How would ZDP be 1 micron while magnacut is 5?

Edit:nvm

 

[jedy617]

https://knifesteelnerds.com/2018/06/18/maximizing-edge-retention/

Look steels don't matter anyway

 

[Bret Koesser]

Just look at the picture. How would ZDP be 1 micron while magnacut is 5?

Edit:nvm

@jedy617 Yeah I get that. Like I said, I didn't have a reliable source on grain size for the other steels so the 1-2 micron grain size could be a fictional unicorn. The picture you referenced also seems like go against Larrin's measurements.

I'm also very familiar with Larrin's assertion that edge geometry is the single most important factor of edge retention. More important than steel, more important than heat treatment, etc. I think that was just about his exact words during an interview with Buck knives. For my experimenting I wanted a knife or two that lived on the end of the steel spectrum with the smallest grain size and I was going to mess with the edge geometry. I don't think we really need to hit on this point much more. We have no disagreement.

 

[jedy617]

Aebl then? Extremely fine grained, folks love it

 

[JayS20]

Sukenaris are really good. Another option was Yoshida hamono.
Liked the one I got o try in Hap40.
Yoshida hamono

 

[aporigine]

Sukenaris are really good. Another option was Yoshida hamono.
Liked the one I got o try in Hap40.
Yoshida hamono

The “The Carbons” set is enticing.

 

[ile74]

https://knifesteelnerds.com/2018/06/18/maximizing-edge-retention/

Look steels don't matter anyway

View attachment 343596

But at the same edge angle steel and HT is everything

 

[jedy617]

It was a joke