Kohetsu western HAP40 150 petty

[jmcnelly85]

A good utility knife is a wonderful thing, as a pro I’ve seen countless get by with a “good enough” stainless that can take a punch and no one cares once it’s dead and gone, it served its purpose. For years this has been my strategy of dealing with mediocre edge retention and continuous sharpening as my cases and cases of product slaughtered keep piling up. I figured I’m gonna try a different approach and see if the HAP40 approach will make my life easier. My initial impressions seem like this will be the case.

Right off the bat, the knife came with a pretty decent edge, no detectable burr and versatile edge through product. Trimming up apples and peppers seemed just as suitable as it did seaming out a 24 lb chuck roll and breaking it into grinder sized pieces. Props to whoever put that edge on, it didn’t even act dainty. Fit and finish on the handle seems perfect, but the blade leaves a little to be desired, some machine marks and scratches are apparent but it’s not really intended to be a beauty queen it’s more of a working object so I’m not really judging it too harsh just letting people know it’s not the smoothest transition from cladding to core steel if that parameter is important to you.

I spent some two shifts with the Ootb edge and probably didn’t “need” to sharpen it, but I’ve long been a proponent of “don’t judge a knife by it’s ootb edge” so I felt it was time for me to see what I can do sharpening the dreaded voodoo steel.

On the stones, starting with a Shapton pro 220, it acts very talkative with a “good carbon” steel level of tactile feedback. Alternating frequently to chase the apex it didn’t seem to take an extravagantly longer time to achieve an apex. I didn’t have any stubborn burr to fight against cause I didn’t raise much, and progressed up to a kohetsu 800 and finally jumping to a shapton pro 5k. The 5k edge took a touch longer to get where I wanted and the final edge was comparable to my srs-15 knife. Higher quality than sharpening a takamura R2 but not quite as nice as my ogata sg2…. Better than a kohetsu blue but in no way on gihei blue or moritaka AS territory. In terms of “ease of sharpening” I’d say this falls right in the semi stainless category… some of the really nice elements of sharpening a carbon but not quite as quick n easy as a simple carbon. I would rather sharpen this than a soft steel or a meh Vg10, but it doesn’t quite act like a pure carbon. If you have a touch more time, it’ll reward you with really nice feedback… all in all it’s a pretty easy one to sharpen if you know what you are looking for hearing and feeling what it’s saying it’s just a touch slow on the stones. Not unpleasant or stubborn, just different.

Versatility against products is pretty surprising, I turned a bunch of peeled russets into smaller, uniform chunks for mashing and there is enough subtly in the grind to make it somewhat nonstick. Not that there is a lot of blade to stick to, but it fared better than my my Aebl artifex petty in this capacity, it skins fish with ease and doesn’t blink at butchering chicken. The handle is a touch thin for my taste but isn’t uncontrollably thin and works better for in hand work than on the board work in that regard so it’s kinda a well I’ll take that trade off even though I’ll probably use this more for on the board butchery than in hand work. As a butcher knife so far it has a good “thin enough for silver skin while enough stiffness and spine for muscle” tip toe balance. Not extreme in thinness and not beefy either. Good Goldilocks on utility. If was looking for a 100’percent garnish laser petty there might be better options, or if I was planning on doing a ton of pork shoulder blade scraping there’s probably better options but it doesn’t seem out of place in either category. I’m super pleased with both different needs.

All in all I’m pretty thrilled so far, I’ll keep updates with more news on edge retention and durability as it sees more use but so far this is a really solid, balanced tool. Thanks
Mark for making these happen.

[TheLegalRazor]

A thorough and informative review. Thank you.

[Radar53]

Great review & I love the subtleties that you bring to it as a pro chef doing this all the time. Thanks, I've still got a lot to learn.

[jmcnelly85]

I took the knife all the way up to 1 micron, the steel really takes to high refinement and kept a very nice bite. It took two heavy, pre-Easter shifts but towards the end of the second day it still rolled through tomatoes just fine, but I did have to flip them from skin side up to skin side down to get through moderately ripe skins. Based off of what I put the knife through and the level of refinement I’ll say unequivocally this has better edge retention than any knife I’ve properly had a chance to use.

On the matter of high refinement, I’m conflicted as to whether or not I want to keep this knife this high up forever or never again. While butchering pork shoulder and tri tip, the sense of tactile feedback to kinda bite and grip through some things is replaced with a zippy “I wanna go fast” dullness. I have a feeling if I get accustomed to this I’ll be more efficient and precise; however, there is something supremely satisfying using a stamped soft steel boning knife with a clean 800 grit edge when you can feel the seams and flow where you need to go. Instead of the carnal tearing your left with a clean whoosh that’s more pushy than swoopy… I really don’t know how to explain it better but it’s unforgiving and I think “the next level” of butchery that I caught a glimpse of and don’t know if I’m there yet. Another thing that’s nerve wracking is in hand work at that level of refinement is something I wouldn’t recommend to everyone, but I didn’t need any bandaids after a case of Brussels.

[Kerneldrop]

...The 5k edge took a touch longer to get where I wanted ,...

As you craft a professional-use edge....what sign(s) do you look to know when you've reached the edge you want or when to keep going as you progress stones?

[jmcnelly85]

In terms of when to progress, assuming I do my heavy lifting early on a coarse stone and have a clean sharp edge, from there it gets hard to explain. Initially, I want an edge that only reflects a black line while looking directly at the apex, doesn’t have any dinks or things detectable with a thumbnail, and reflects light evenly from heel to tip without waves or off spots. If it not just cuts a rolled up paper towel but attacks it from heel to tip and just overall seems sharp I know I can make my first jump.

After the heavy lifting, part of it is knowing where other knives feel and act on phonebook paper, rolled up paper towels, and fingerprints, part it is gut. If I cut phonebook paper and it doesn’t whisper like it should I’ll keep going, or if I start losing teeth I’ll jump back to the previous stone and finish on it. Some knives I have I’ll know where they stop refining and start losing their toothiness (I don’t know a better term to use for this). I can continue to polish that edge but I’ll just be polishing a turd at that point. Other knives I know I’ll need strops and compounds beyond 1 micron if I wanted to find the limit of how refined they can go. The hap40 certainly acts like it can exceed 1 micron. With my
Current setup 1 micron cbn emulsion on a balsa strop followed by bare leather is as far as I can go.

In terms of the edge I want, I usually go through an experimental stage based on products it’ll likely see and figure out where the knife wants to be coupled with how I use it. I have a white steel itto ryu nakiri that I used to dig for having meh edge retention until I realized it holds an edge best at 1 micron. My kurosaki seems to really like being at 3 micron, blue 2 kohetsu at 2k, 52100 artifex at 800 grit (even though it’s capable of a 1 micron edge).

Long story short I really putz with edges until I feel the knife and I come to an agreement. This week on the hap40 ingot everything I can on a 2k and barely stropped it on a 1 micron strop and so far the results seem more in control than the maxed out 1 micron… when it needs a touch up I’ll try a different edge, maybe a maxed out 800 with a “too big a jump” stropped on 1 micron or something… we’ll see.

[Kerneldrop]

Thank you very much for your time and thorough reply.
I was curious how you went about it because although I can sharpen to a usable edge, I don't know how to craft an edge.
I just go through the motions of a progression without knowing what I should have done less or more of. I guess I'm at the caveman stages where I see sticks, rub sticks, start fire...but my sharpening game is headed towards edge crafting. For years I've machined sharpened on 1x30 belts and MDF wheels...and there's not much crafting an edge at 1900 sfm or 3500 rpm. You get razor sharp, but you get what you get on machines.

One aspect of sharpening that keeps me entertained as a hobbyist is that the best technique on the planet won't get me a crafted edge....it's about using that technique and knowing what to do, when to do it and for how long.

[jmcnelly85]

One of my favorite Ken Schwartz philosophies he used to say all the time is that “there’s sharp, but there are different kinds of sharp.”