S110V at 59 Rc

[Twindog]

Answers:

1) Wear resistance - S110V
2) Easier to sharpen - ELMAX
3) Strength - About the same
4) Corrosion resistance - S110V

Thanks, Jim, I really appreciate your thoughts and your direct answer to my question. I struggle with this because we talk about steels as if hardness makes no difference. In reality, hardness is a key component in how steels will react, as you know from your testing.

For example, just one point of hardness advantage can give S90V better edge retention than S110V.

According to Bohler, when Elmax is taken from 58.5Rc to 61Rc, it loses about 28 percent of its toughness.

When Elmax is taken from 60+Rc to 62Rc, edge retention is increased by 22 percent.

So when we compare ZT’s Elmax at 60-62Rc to ZT’s S110V at something close to 59Rc, say 58 to 60Rc, we could be comparing an Elmax blade at 62.5Rc to an S110V blade at 57.5Rc – potentially 5 points of hardness. That difference is huge, although on the extreme end of what we’d normally see. However, we also see where users of Elmax blades can love the steel or hate it, even in the same knives. My own sense is that those differences in experience are likely the result of comparing differences in hardness that come from the natural variation in hardness from knife steels from the same manufacturer.

http://www.knifeblog.com/knife-steel-comparison-charts/
http://www.crucible.com/PDFs\DataSheets2010\Datasheet CPM S110Vv12010.pdf

 

[jimmer_5]

If the answer is as simple as "running it harder won't work with the composite blade" or "that heat treatment protocol is far more involved and would have added significant cost" or "we were looking for a balance of toughness and edge retention", then I think people would say ok cool it's answered and then move along. Obviously someone in the company chose to run the s110v at 59 HRC and they had a reason for it. The question is why run it at 59 HRC? I imagine the answer is very straightforward.

I do believe jimmer told us that If it was ran harder it would melt the brazing.
Take that with a gain of salt because I'm not entirely sure.

I can understand why this conversation came up, but I think at this point, the simple version will be best: Our current composite blade technology still relies on the use of copper to form the braze weld between the two steels. We have tried other materials and methods (and continue to try) but as of right now, copper is still the toughest, most manufacturable solution. Our customers really like our composite blades, so we continue to make them. In this case, we came up against the melting point of copper versus the temperature required to get the blade above 59 HRC. It's as simple as that.

When these blades came back from heat treat at 59 HRC, we did some informal testing, and we found that the S110V composite blades still performed very well. You will note that I am not speaking in scientific terms here, but rest assured that the Composite S110V blade still outperformed other high end steels that we tested it against.

We could, of course, offer solid S110V blades and that would allow us to offer a higher Rockwell on the blades. There will be plenty of other knives where we do just this. However, several people have hit on the other side of the argument - maximum hardness is not always the best solution for everyone. Too hard and people complain that the blade chips and is difficult to sharpen. Too soft and people worry about edge retention. We give these decisions a lot of thought, and your opinions do enter our discussions.

I understand that Bladeforums is a place for debate, but at this point, this particular run of knives is complete. The knives are what they are, and no amount of debate will change that. If you disagree with our decision to release these knives at 59 HRC, that is your privilege. However, please keep in mind that there will be others who will buy this knife and find that it performs admirably for them. Not everyone will be best served with a super hard blade - many people will actually be better off with a softer (read tougher) blade for the particular kind of abuse they inflict upon their knives.

Thanks,

- Jim

 

[Ankerson]

Thanks, Jim, I really appreciate your thoughts and your direct answer to my question. I struggle with this because we talk about steels as if hardness makes no difference. In reality, hardness is a key component in how steels will react, as you know from your testing.

For example, just one point of hardness advantage can give S90V better edge retention than S110V.

According to Bohler, when Elmax is taken from 58.5Rc to 61Rc, it loses about 28 percent of its toughness.

When Elmax is taken from 60+Rc to 62Rc, edge retention is increased by 22 percent.

So when we compare ZT’s Elmax at 60-62Rc to ZT’s S110V at something close to 59Rc, say 58 to 60Rc, we could be comparing an Elmax blade at 62.5Rc to an S110V blade at 57.5Rc – potentially 5 points of hardness. That difference is huge, although on the extreme end of what we’d normally see. However, we also see where users of Elmax blades can love the steel or hate it, even in the same knives. My own sense is that those differences in experience are likely the result of comparing differences in hardness that come from the natural variation in hardness from knife steels from the same manufacturer.

http://www.knifeblog.com/knife-steel-comparison-charts/
http://www.crucible.com/PDFs\DataSheets2010\Datasheet CPM S110Vv12010.pdf

Actually if you would compare S90V at 61 to S110V at 59 they would be very close in performance, but due to the higher percentage of carbide forming alloys in S110V I doubt S90V would out perform it, more like maybe be too close to call.

But then we normally don't see S90V that high anyway, more like 59-60 so make the comparison apples to apples as in 59/60-59 and S110V will come out on top assuming proper processing.

This is coming from someone who uses S110V almost everyday and can say that the steel is really in a class by itself due to the alloy content.

 

[Allen R.]

Can't please everyone, but it looks like KAI is trying their best to, gotta give them credit for that :thumbup:

 

[NeverMore1701]

I can understand why this conversation came up, but I think at this point, the simple version will be best: Our current composite blade technology still relies on the use of copper to form the braze weld between the two steels. We have tried other materials and methods (and continue to try) but as of right now, copper is still the toughest, most manufacturable solution. Our customers really like our composite blades, so we continue to make them. In this case, we came up against the melting point of copper versus the temperature required to get the blade above 59 HRC. It's as simple as that.

When these blades came back from heat treat at 59 HRC, we did some informal testing, and we found that the S110V composite blades still performed very well. You will note that I am not speaking in scientific terms here, but rest assured that the Composite S110V blade still outperformed other high end steels that we tested it against.

We could, of course, offer solid S110V blades and that would allow us to offer a higher Rockwell on the blades. There will be plenty of other knives where we do just this. However, several people have hit on the other side of the argument - maximum hardness is not always the best solution for everyone. Too hard and people complain that the blade chips and is difficult to sharpen. Too soft and people worry about edge retention. We give these decisions a lot of thought, and your opinions do enter our discussions.

I understand that Bladeforums is a place for debate, but at this point, this particular run of knives is complete. The knives are what they are, and no amount of debate will change that. If you disagree with our decision to release these knives at 59 HRC, that is your privilege. However, please keep in mind that there will be others who will buy this knife and find that it performs admirably for them. Not everyone will be best served with a super hard blade - many people will actually be better off with a softer (read tougher) blade for the particular kind of abuse they inflict upon their knives.

Thanks,

- Jim

Even though I'm one of those who would have like it if you could have made the blades a couple of points higher, I understand the manufacturing limitations you guys face, and am still very pleased with the knife. It is a beautiful, superbly made piece that I am very happy to own. I think I speak for all of Kershaw/ZT's fans when I say that I really appreciate the time, effort, and money you put into bringing us these outstanding designs, especially when you venture out into the realm of more exotic materials and building methods. You guys are great, your knives are great, and please don't take idle musings from the peanut gallery (such as myself) to mean any different

 

[Twindog]

Thank you, Jimmer_5. Much appreciate that explanation. It's an incredible knife. It's nice to know the thinking that went into the design.

 

[RevDevil]

Thanks Jimmer, I've very pleased with mine, and it will be used. We truly do appreciate the end result.

 

[Fanglekai]

I can understand why this conversation came up, but I think at this point, the simple version will be best: Our current composite blade technology still relies on the use of copper to form the braze weld between the two steels. We have tried other materials and methods (and continue to try) but as of right now, copper is still the toughest, most manufacturable solution. Our customers really like our composite blades, so we continue to make them. In this case, we came up against the melting point of copper versus the temperature required to get the blade above 59 HRC. It's as simple as that.

Thank you for replying with a straightforward answer. I didn't and still don't understand why the other moderator was going on about people questioning ethics and why that moderator chose to avoid directly answering the question. So, you can't run the composite blade above 59 HRC because of the heat required in the thermal processing of s110v. That's a very simple, direct answer to the question. Thank you.

The followup question I have is why not heat treat each portion of the blade separately and then weld together?

 

[CrimsonTideShooter]

Thank you for replying with a straightforward answer. I didn't and still don't understand why the other moderator was going on about people questioning ethics and why that moderator chose to avoid directly answering the question. So, you can't run the composite blade above 59 HRC because of the heat required in the thermal processing of s110v. That's a very simple, direct answer to the question. Thank you.

The followup question I have is why not heat treat each portion of the blade separately and then weld together?

Because in order to braze the two pieces together the base metals (two halves) must be be heated (think about how solder doesn't bond well if the work piece isn't hot). That process would ruin the HT on the blade.

 

[Kai Corp.]

I didn't and still don't understand why the other moderator was going on about people questioning ethics and why that moderator chose to avoid directly answering the question.

Because there was some posting here that I felt were questioning our ethics, and being rude. Still feel that way.

I'm not always going to answer every question. I'll assume that is ok? You don't have to answer that.

 

[NeverMore1701]

It's not ok. You're here to be our slave, and we demand answers!

 

[JuJu-]

Thank you for replying with a straightforward answer. I didn't and still don't understand why the other moderator was going on about people questioning ethics and why that moderator chose to avoid directly answering the question. So, you can't run the composite blade above 59 HRC because of the heat required in the thermal processing of s110v. That's a very simple, direct answer to the question. Thank you

If you go back to the first page, sticktodrum did give that specific answer. If you followed anything over In the kai subforum( which I have seen you over there) this has been discussed by jimmer and others to great lengths.

Thanks jimmer and kai corp for taking the time to answer the questions. Good luck at blade, not that you need it though!

 

[eodtoad]

Questioning ethics? I see people questioning the chosen heat treatment, not ethics. There's no need to be defensive about it. If the answer is as simple as "running it harder won't work with the composite blade" or "that heat treatment protocol is far more involved and would have added significant cost" or "we were looking for a balance of toughness and edge retention", then I think people would say ok cool it's answered and then move along. Obviously someone in the company chose to run the s110v at 59 HRC and they had a reason for it. The question is why run it at 59 HRC? I imagine the answer is very straightforward.

:thumbup: :thumbup:

 

[AF]

If you go back to the first page, sticktodrum did give that specific answer. If you followed anything over In the kai subforum( which I have seen you over there) this has been discussed by jimmer and others to great lengths.

There are other people like me reading this thread who don't follow what's going on with Kai. That answer (from the company) took a long time and what came before it wasn't pretty.

 

[Twindog]

Deleted because this is the wrong place to discuss knife steel.

 

[TotalDbag]

Yea, I got quoted by a mod.......I feel special

 

[DapperDan]

I suppose it's time for us to move along here.

We do the best we can with what we have knifenut1013. It doesn't always please everyone. Not everyone get's it every time. Our intentions are to please. Sorry it didn't work out for you and others with this one. We're quite pleased with the final pieces that are on the street.

Thanks for the conversation.

Hum... You seem familiar.

As to this account, it's answers, and the information that come from it, are presented by committee. From our engineers, Tim Galyean, our other designers, to our long time industry professionals, we take input from all of our resources. The answers will come from of all us through one voice.

Is that voice Thomas?

 

[TotalDbag]

Hum... You seem familiar.

Yes......many people agree.

 

[Kai Corp.]

Hum... You seem familiar.

DD, this account has been discussed and answered in this thread, but to take it a step further for you.

Mr Welk, along with others will have input with this Mod. handle. Some of the posts will be his and some will be others, all written by me. As I mentioned, this Mod. duty will be done by committee. There is not time enough for one person to handle this. As it is Jimmer spends too much time here.

As you can imagine, being a manufacturer here comes with a lot of work and headaches. We need all the help we can get to assist in keeping the peace.

Thank you for your understanding.

Kai Corp

 

[Vicarious Reality]

The ZT 0560CBCF is your basic awesome. It has amazing fit and finish. The edge is evenly ground at 19 dps

Nineteen damage per second? lol


Thin, soft composite blades is CS grade BS in my book