Is HAP40 prone to chipping?

[animportant]

I am interested in the upcoming endura sprint but I have been reading that while it will make an exceptional cutter of soft materials, it should not be hard used. Can anyone speak to this? Sal, I believe you are carrying a prototype.. Any issues?

[Surfingringo]

Hi animportant. Would you share your source for this information?

[tvenuto]

I think it's worthwhile to remember that given a proper heat treat, an edge will either chip, deform (roll), or wear smooth with use. None of these outcomes is necessarily "better" in an absolute sense. For instance, chipping could cause a knife to maintain low sharpness slicing aggression practically indefinitely, and thus might be the preferred blunting mode. If someone wanted to maintain their edge via steeling, however, they would probably prefer a knife that was more prone to rolling without chipping.

Also, "hard use" is incredibly vague. Someone could define cutting rope for 7 hours straight as "hard use," but as I mentioned chipping might actually be an advantage in that scenario. I think most people confuse "hard use" with "careless use." I would probably agree that these knives in boutique steels have less margin for careless use than an inexpensive knife in 420 stainless. Of course, this is the consequence of us knifeknuts always asking for Spyderco to push the limits of performance. Case in point, there is currently a thread asking for more aggressive heat treating of steels.

[animportant]

http://www.cliffstamp.com/knives/forum/ ... p?24,44062" onclick="window.open(this.href);return false;

http://www.chefknivestogoforum.com/kohe ... t5787.html" onclick="window.open(this.href);return false;

A kitchen knife maker that uses this steel advises against use which may very well be within the characterists of irresponsible use.

That's a good point about small chipping vs rolling, I have thought about that before. I guess that is the kind of edge characteristic/quality (dendritic teeth) produced in the Serrata.

[MacLaren]

Sal said it is an exceptional steel. Thats plenty good for me. Ymmv.

[animportant]

With all due respect, that's exactly what the cliffstamp forum was saying. That us spyderco junkies will eat up anything that comes out. Just wondering how hap40 will compare in use to the standard vg10 the endura and delica use, as well as CPM m4, which it is being compared to (sans cobalt)

[Surfingringo]

http://www.cliffstamp.com/knives/forum/ ... p?24,44062

http://www.chefknivestogoforum.com/kohe ... t5787.html" onclick="window.open(this.href);return false;

A kitchen knife maker that uses this steel advises against use which may very well be within the characterists of irresponsible use.

That's a good point about small chipping vs rolling, I have thought about that before. I guess that is the kind of edge characteristic/quality (dendritic teeth) produced in the Serrata.

Hi animportant, I just read the entire thread from Cliff's forum. I could not find a single post that talked about the performance of the steel or even one that speculated what the performance might be based on composition and ht. I also saw no posts relating any first hand experience with the steel. All I saw were posts saying that marketing and hype were the bane of the knife world. If you drew from that thread the conclusion that this steel would be prone to chipping then that could only have been inferred from the marketing blurb in post #5. This would be quite ironic given the tone of the rest of the thread, which was that marketing was near meaningless and would be better left ignored. :)

I'm not trying to be confrontational at all, just trying to be open minded about a steel that we have limited experience with. Thank you for the links. I am going to read the second one now. My plan is to buy one of the new Delicas, which will be a new steel in an affordable platform, and draw my own conclusions based on actual use and sharpening.

[FCM415]

SO... After several years of members requesting for a new Japanese steel to be offered on various request threads, Sal obliged. There does not seem to be many other options mind you as I recall, the only other steel that kept popping up in discussions is the White steel. Sal regulary goes to Japan, talks with these knifemakers and concluded that HAP40 would be a good viable steel to offer. I'm not sure why the smart one feel it necessary to hold such negative positions about the most common business practice: Offer what your customers want. Of course, the Cliff Stamp spin on things is that Spyderco is not what it used to be and the rhetoric that Spyderco.com form members are fools continues on his own forum. What's new. Next is that I get blamed :o

It was a lot more about the forum being a bunch of inept sheep and scientifically quantifying how evil Spyderco is than anything else.

[Ranger393]

Ah,, there's the source. CS

Source aside, the performance characteristics of hap40 is a good question. I'm thinking about getting an Endura with the new steel and would like to see some specs. I do apologize in advance if those are already posted somewhere here in the forum.

[FCM415]

Let's look at the track record before we let a fear mongering develop.

Spyderco is constantly one of the first to push Japanese steels to mass market. Gin1, VG10, MBS, Super Blue, H1... Successful or at least the feedback is overwhelingly positive. Shouldn't they get the benefit of the doubt?

Just an example, they were the very first of the production knife companies to offer CTS-XHP, now it is becoming a common steel. That has happened for other steels also. It's not always going to be a success and what we are ALL good for including Cliff Stamp is in the learning process of trial and error and giving feedback. What is not useful is acting like we are above anyone else because we think we know something. Making accusations for the sake of having the high ground.

[sbaker345]

Its a valid question, I wouldn't imagine hap40 would be a good steel for something that would hit staples and the like often. But its impossible to say without actually playing with the sprints first, Reason being most high end chef's knives are hardened to the extreme and often at very acute angles.

You can't really draw conclusions on how a steel at 65HRC and 30 degrees inclusive will behave based on one at 68HRC and 20 degrees inclusive.

I actually hope Spyderco hardens it fairly hard though.

[Ranger393]

Point well taken FCM415. At the end of the day CS got exactly what was wanted out of this thread,,, a mention of his forum and multiple mentions of his name. I agree with gringo that it's best to get one of the entry level hap40s, i.e. Endura for me, and give it a go and provide real world feedback.

[elena86]

I have no experience with Hitachi HAP40 but being a mechanical engineer I can read behind a data sheet.It's a powdered high speed steel.According to data sheet HAP40 should have very good toughness and apex stability so, to answer to your question, no, it should not be prone to chipping.AFAIK it could be hardened between 64-68 HRC but it seems the most common hardness in kitchen knives is 65 HRC. I am a little woried about that cobalt amount.It's a great steel but me, I'm still a CPM-CRUWEAR guy when it comes to semi-stainless steels.

[sbaker345]

I have no experience with Hitachi HAP40 but being a mechanical engineer I can read behind a data sheet.It's a powdered high speed steel.According to data sheet HAP40 should have very good toughness and apex stability so, to answer to your question, no, it should not be prone to chipping.AFAIK it could be hardened between 64-68 HRC but it seems the most commun hardness in kitchen knives is 65 HRC. I am a little woried about that cobalt amount.It's a great steel but me, I'm still a CPM-CRUWEAR guy when it comes to semi-stainless steels.

My Cru-Wear Manix 2 is still in the box tempting me to use it

[sal]

The proto has worked well with no problems cutting anything tried. Edge retention has been good as well. Sharpened it once. 30 degrees.

I don't think there is a lot of real world use on the steel and I'm looking forward to getting feedback from the group here.

sal

[sal]

Hi Ranger,

Welcome to our forum.

Be careful. This is a strange group. You've heard of "near the edge" or "over the edge". This group is OC about the edge. :p

sal

[Cliff Stamp]

I am interested in the upcoming endura sprint but I have been reading that while it will make an exceptional cutter of soft materials, it should not be hard used.

HAP40 is a high cobalt HSS, similar to M4. The very high cobalt levels are in HSS because it provides exceptional heat resistance and thus has benefits and drill bits and similar. Aside from that, the material properties will be similar to M4. Thus if you are happy with the performance of M4 then you will be with HAP40.

As for can it be "hard used". Imagine yourself being a knife maker and trying to answer that question. Even if you knew what the guy was doing there is so much variation in application. How hard and fast does an individual cut? How much twisting does the person do, what happens when a blade binds, do they just twist it out?

Considering how much some of these can vary from person to person it is very difficult, if not impossible to know if an individual can do something without damage to a knife in a given steel. The most you can do in a practical sense is ask them what they can use without damage and see if it is comparable.

Thus in short, if you can use M4 without damage then you likely will be able to use HAP40 without damage.

[sal]

I guess I'm one of those that likes to experience things for myself and I would guess a lot of you are that way. It's a lot different going 120 on a scooter than it is reading about going 120 on a scooter.

I know you will find it hard to believe that someone will actually lie to you to get your money. :eek: I try to be straight. The use of these odd runs of steel gives me, and you the opportunity to do some of our own testing and learning. I get to learn from my own experiences and also get to share what I learn with what you learn. I don't think we hype much, though others might. In any case, I am available for questioning.

sal

[Liquid Cobra]

Is HAP40 a non stainless steel?

[tvenuto]

Is HAP40 a non stainless steel?

With 3.7-4.7% chromium, it would not be considered a stainless steel.