Spyderco/Farid K2

[Stuart Ackerman]

Well done Farid and Spyderco!

[Able Dog]

Rest well, and we will hope you have a speedy recovery.

Best wishes.

[Laethageal]

I wish you good luck with your recovery. Others already expressed it, but it's great seeing knifemakers like you doing a colaboration with Spyderco coming here and sharing with the community!

[Cliff Stamp]

Farid,

Can you describe/provide any background on the design of this knife from a functional perspective as it doesn't seem on the surface to be a consistent design. As in some ways the knife looks to be designed for heavy work, to be able to take considerable loads/impacts (stock thickness, handle/lock, etc.). However the steel used is one of the most brittle with the lowest grindability of current cutlery steels which is almost the exact opposite of the previously noted factors. What kind of work exactly was this designed to do well?

[faridknives]

Farid,

Can you describe/provide any background on the design of this knife from a functional perspective as it doesn't seem on the surface to be a consistent design. As in some ways the knife looks to be designed for heavy work, to be able to take considerable loads/impacts (stock thickness, handle/lock, etc.). However the steel used is one of the most brittle with the lowest grindability of current cutlery steels which is almost the exact opposite of the previously noted factors. What kind of work exactly was this designed to do well?

Cliff,
I can answer all your questions but I choose to let my work speak for itself, also I have noticed every time you have used my good name on YouTube or other forums you have tried to damage my reputation so I refuse to answer your questions as it is my right not to.
Farid

[Cliff Stamp]

.... I refuse to answer your questions as it is my right not to.

Of course, I ask the questions as I believe they should be asked as it is only through asking them that differences in perspectives can be realized, though this means both parties have to have the same view.

Clean design in any case.

[MacLaren]

Farid, get well buddy.
The K2 will be a smashing success!

[Wanimator]

Thoughts and prayers go to you as you heal.

[faridknives]

Thank you all for your support. I'll be back on my feet soon.
F

[Laethageal]

Farid,

Can you describe/provide any background on the design of this knife from a functional perspective as it doesn't seem on the surface to be a consistent design. As in some ways the knife looks to be designed for heavy work, to be able to take considerable loads/impacts (stock thickness, handle/lock, etc.). However the steel used is one of the most brittle with the lowest grindability of current cutlery steels which is almost the exact opposite of the previously noted factors. What kind of work exactly was this designed to do well?

I wonder if the steel is really one of the most brittle as you say Cliff. Phil rate it as one of it's best edge retention steel, and to quote one of your review of a Phil Wilson knife in 10V, you say : "As noted in the above the edge isn't fragile, and it takes some pretty serious cutting to do any direct damage"
"The knife was then used to cut strips off of a mild steel bar The pieces were small, maybe 0.5 of a centimeter in length and a dozen cuts were made in total. The edge was now blunted significantly and had numerous spots were the light reflecting due to impactions or rolls. These distortions were still not visible at arms length. Finally the blade was used as a chisel to cut the edge off of the Calypso Jr., the custom CPM-10V blade still did not chip out."

From what I understand, it's not that bad at all. Care to explain me if I'm wrong?

[Cliff Stamp]

I wonder if the steel is really one of the most brittle as you say Cliff.

It is a very high carbon, ultra-high carbide steel, the only steels more brittle than A11 are things like 121 REX. Now you can always say well I am going to define tough to be A11, you can pick your starting point to be anywhere. But that would be like saying 4340 has high wear resistance and L6 has high corrosion resistance. I mean you could, they are just relative descriptions - but that seems kind of silly right? If 4340 has high wear resistance then what do you say about A2 let alone D2 or T15. 4340 has one of the lowest wear resistances of cutlery steels just like A11 has one of the lowest toughness levels. Put 4340 and A11 in an impact machine and watch one of them bounce the hammer off it and the other one have the hammer go through with almost no loss of energy.

In the above quote the edge is being loaded slowly so it is a check on strength not toughness, I should have said weak to be specific. I wasn't always the most careful about materials terms when I started writing. A lot of that work was from ~15 years years ago when I was actually studying physics as a u-grad and had just started learning about metallurgy. I keep meaning to go back and clean up a lot of the articles but it is just a monumental amount of work and the time I would spend on that would be time I would not actually be learning anything new. All I would say to anyone reading it is keep in mind the time when it was written, the knives that are being compared/contrasted to, especially when relative terms are being used. No different than if you read my BSc the methods I used were very basic compared to even my MSc.

A lot of what I considered to be very high performance then I don't now, simply because I didn't have the experience. If you take someone who has never used a decent knife before and give them a Cold Steel Trailmaster it seems awesome. However given them a similar knife from Joe Calton, cKc knives, etc. and the Trailmaster doesn't seem so impressive anymore. If you ask me a question now and then next year you won't get the same answer, if you did it just means I didn't learn anything in an entire year on that subject and spent a year being just as ignorant.

--

Now a critical question however is - is it tough enough? This is no different than White steel has an extremely low corrosion resistance but you can still ask is the corrosion resistance high enough for a kitchen knife. Or S7 has a very low wear resistance, but is it high enough for a machete / brush blade. These are all very interesting questions - hence why I asked one of them. Other makers have been exploring these questions and we are starting to see some very interesting blades being made using steels which are ultra-tough but have very low wear resistance because the question is how much do you really need in a large knife? Is a knife made out of H13, 4340 etc. really "inferior" to a knife made out of 1084 when you are chopping wood and brush?

I see that design (K2) as being completely incongruent to the point it makes no sense at all, it would be like taking a salt water fishing knife and making it out of L6, the steel has the complete opposite set of properties. If someone did that then I would ask the question obviously. And in fact I have done that and got actual sensible answers, such as :

-steel was free (very common as it is a saw blade steel, a lot of hobby guys use it)
-easy to grind, works great with a butcher's steel
-corrosion resistance doesn't matter anyway the knives are frequently lost/misplaced before they rust away
-the shiny ones get robbed, no one takes the rusty knives

and then you understand why someone would use a steel which at first glance makes no sense but that is because what you are using to evaluate it is very different than what they are, hence you ask so you can understand and people answer so that is possible.

[tvenuto]

Perhaps there were some crucial differences between the knives that paraphrasing won't explain? Just speculating/playing devil's advocate.

I don't think Cliff is saying that the knife will be inadequate by any means, I'm going to hazard an analogy:

Let's say when "Hummer" came out with the H1, they put Z rated, not even rated for snow, low profile, street tires on it. Now, these are perfectly good tires, and fine for driving around, but at their limit, compared to other tires, they excel at performing at high speeds on perfectly paved roads. The rest of the H1 design seems generally ill suited to do this, and it would seem that off-road tires would be a choice more consistent with the design. The fact that 95% of the H1 owners will only drive their cars on the highway at moderate speeds doesn't make the choice less strange, especially when perhaps there was more expense associated with the Z rated tires. Cliff did not suggest that wooden tires were put on the H1, which are ill performing for everything, he merely made a comparison to the other available options.

I for one thought it was a valid question, not an attack. People tend to bristle at the word brittle, but it's merely a description of a particular steel property, not a categorically negative statement on the steel. From the quote above, clearly Cliff doesn't disagree with its use in knives.

Edit: I see that Cliff has responded already, but I'm going to leave this up because I like analogies.

[Cliff Stamp]

From the quote above, clearly Cliff doesn't disagree with its use in knives.

I have lots of knives in very brittle steels, many of them are actually quite functional. Not every knife needs to be tough just like not every knife needs to be stainless or every knife needs high wear resistance.

A few years back bainite started to get a push and there is no argument about bainite and toughness. Kevin Cashen was one of the first people to ask the obvious question - do you find the martensite knives you have in 1084/L6/5160 to be limited by the toughness? Are the ABS bowies, machetes, parangs etc. all snapping, chipping and breaking by fracture? Because if the answer to this isn't yes, well then making the blade tougher doesn't necessarily gain you anything, and it might cost you something if you lose other properties.

The same is true of other properties, where does the knife fail in use and how - that is what you have to improve to get a "better" knife.

[Laethageal]

I get your point. Thanks for your great explanation.

How would the toughness of 10v compare to ZDP-189, in regards to chipping?

[Cliff Stamp]

How would the toughness of 10v compare to ZDP-189, in regards to chipping?

Interesting question. I am actually doing a comparison run now on k390 on hard cutting (carpet). I'll add in a ZDP-189 knife with the same edge angle/thickness and see if it is significantly different.

[sal]

I'm not Farid, but I'll share. Farid said he wanted a folding knife that would be large enough for many tasks, be reliable if away from support (out doors for a long time) and have good edge retention as sharpening equipment might not be easily available. He felt the combination of blade shape, Titanium, (for lighter and stronger) "Reeve-Integral-Lock" and 10V would provide the best options for this situation.

sal

[Ankerson]

I'm not Farid, but I'll share. Farid said he wanted a folding knife that would be large enough for many tasks, be reliable if away from support (out doors for a long time) and have good edge retention as sharpening equipment might not be easily available. He felt the combination of blade shape, Titanium, (for lighter and stronger) "Reeve-Integral-Lock" and 10V would provide the best options for this situation.

sal

Hi Sal,

I concur. :)

Having tested a number of different A11 steels personally I don't see any problems choosing CPM 10V.

Jim

[Brock O Lee]

I for one thought it was a valid question, not an attack.

+1

Thanks for asking the "difficult" questions Cliff. I always find it very insightful to understand a makers reasoning and design choices about a specific model.

I really hope Farid would reconsider his no-comment answer.

[Philo Beddoe]

I don't think Farid or anyone else owes anyone a explanation..

It will either work for you or it want..

[Stuart Ackerman]

I don't think Farid or anyone else owes anyone a explanation..

It will either work for you or it won't..

Explanations help the buyer decide what to do... :)
I like this knife, regardless of whether Farid decides to answer or not, but others may need persuasion/convincing? :)