13C26 Razor Blade Steel -- a Kershaw Junkyard Dog II Review

[Larrin]

BTW, the .6 micron average is taken from Verhoeven's book. He doesn't make clear what austenitizing temperature this is using.

 

[rosconey2]

ok hows this sound-i have a brand new jyd and mini cyclone zdp due this week(with 3 other knives in shipping also )

why-because thomas is a stand up guy -and represents kershaw well-

ill post real world experience with them from my job-so far my s30v strider pt is the best at edge retention in my testing-lol

 

[Cliff Stamp]

Ok, what other steel could be used for a quality $50 dollar knife?

Most knife steels, assuming you are looking for high edge stability are actually very cheap in terms of initial cost, grinding and heat treating. Steels made to take and hold a very high push cutting sharpness are quite simple in chemistry.

The complex steels are more expensive but for reasons of other properties like high hot hardness or extreme wear resistance, the latter just lets a knife stay at not very sharp for a long time. Has its uses though for knives for some.

D2 is a good example of that type of steel, fairly expensive, hard to grind, much more complex to heat treat than 1095. Something like CPM-15V would be an extreme example.

I have NEVER put a restriction on any of our field testers.

Yeah you have, I have the emails from the testors. You are lying directly. You want me to post the emails where they say directly you placed restrictions on them.

I was trying to get the edge to chip, it did not.

That is the benefit of high stability steels, I noted this months ago when Kershaw started using the steel in edge profiles which were the exact opposite of how the steel was designed to be used.

-Cliff

 

[DG2244]

Yep, only takes one KID with a poopy diaper to stink up an entire room. Nice job Cliff!
DOG, nice review, to bad someone stole your thread.

 

[Cliff Stamp]

BTW, the .6 micron average is taken from Verhoeven's book. He doesn't make clear what austenitizing temperature this is using.

Landes has about one or so at 1050C, Verhoeven is likely close to 1100 C. These numbers though are averages, you really have to be careful when citing them to not quote them as if they were meaningful to that precision. They really are not significant in terms of microns.

Spot checks on the microstructure in the same steel would never be that close together, you can see this from Landes micrographs if you just imagine quarter panel individual averages. The CI's would be much larger than a micron.

You can also estimate the size directly from the razor blade paper I sent awhile back which gives the retain primary carbide volume because you would expect the size to be proportional.

What I find rather interesting is that 13C26 is near ideal for a razor blade steel (promoted anyway). It would seem logical to just eliminate the primary Cr carbides completely by taking something on the carbon saturation line and just increasing the C content to get maximum hardness. Of course this reduces stainlessness which is important for actual razors so it might be that 13C26 hits a total sweet spot.

It however does raise the point about nonshaving uses, I don't see why 13C26 would be above carbon steels which have much finer carbides (Cr carbides are huge in comparison to cementite) so it would seem something like 1095 (with less C) would be ideal, maybe with tungsten or similar for grain refinement, i.e., F2 or similar. Hopefully Landes will discuss this in more detail in his next book.

-Cliff

 

[db]

It however does raise the point about nonshaving uses, I don't see why 13C26 would be above carbon steels which have much finer carbides (Cr carbides are
huge in comparison to cementite) so it would seem something like 1095 (with less C) would be ideal, maybe with tungsten or similar for grain refinement,
i.e., F2 or similar.

LOL who really didn’t see this coming once 13C was more readily available.

 

[thombrogan]

I'm a big fan of 13C26 ran between RC59-61 (and since I'm obese, I'm a big fat fan of the steel!) especially when it's hollow ground and the width at the top of the edge is about 0.012-0.015" and the edge is highly polished. It outperforms S30V at similar dimensions for cutting thick plastics and hardwood and when it takes damage, it's very tiny dents instead of slightly larger than very tiny chips. I try to thin all of my edges to less than 0.01", but they don't get there most of the time.

The one edge I do know reached a proper dimension was my 'worn out' paring knife blank from Alvin Johnston. Raising a burr on both sides of a 0.032" thick by 0.25" wide blade with a hollow grinding wheel (and placing the top of the hollow between 2/3 and 3/4 from the spine) pretty much assures a good cutting edge will be made. Alvin's special heat treatment assures his blades have the hardness and torsional strength needed for enjoyable cutting. It's fun watching steel conform to a ceramic hone as though it were a film of plastic. If any reader has sharpened a Johnston-made 'blank,' without hollow-grinding, please know you're not getting anywhere near the performance offered by the knife (and Johnston is a convexed edge fan).

The problem I have with a properly formed edge with properly selected steel is that I'm a monkey. Monkeys cut hard and tough binding materials with knives; kydex in my case; and wonder why large chunks of steel are missing from the edge when we cut at skewed angles or pry here and there. Having a high-precision cutting tool doesn't mean the skills to use it to its fullest will flow without work.

This brings me back to 13C26 as it's used by Kershaw with Kershaw's heat-treatment and Kershaw's edge-widths. Except for their Storm II folding pocketknives (the larger of the two Storm knives), the edge-widths are 0.02" thick give or take and sometimes even thinner (as on my 440A Leek). At that level and even 50% thinner, 13C26 has a high enough hardness in the RC59-61 range to support a highly polished edge for a wide variety of cutting. For plastics and hardwoods, it outlasts S30V and is slightly ahead (chip-resistance) and behind (wear-resistance) VG-10 in various aspects. When it's thinned down to approximately 0.012", no, it won't cut like 1095 thinned down to 0.0004", but it will handle most every-day tasks without the person holding the knife having to take care beyond basic safety. For the knife user used to S30V tactikewl stuff, it's an upgrade with a lower price. A taste of the good life at a good price (and a special edition of partially serrated JYD II's with a Sears/Ty Pennington tie-in would help reinforce such things). Even those Storm IIs can be thinned out with less than four minutes of belt-sander loving with a fresh 100 grit belt (which, after struggling for hours with normally-fast hones, is always nice).

Would it work better at a higher hardness? In terms of going thinner, it could. In terms of resisting deformation; a larger cause of dulling than wear-resistance in most folders; it could, too. The questions are:

Are there heat-treatment recipes which would uniformly bring 13C26 to a higher level of hardness without a high level of surprizes?*

Can these recipes be used with very large batches of knives without compromising reliability? If not, by what magnitude must the batches be shrank?

Would the consumer benefit from higher-hardness knives ran at geometries used by Kershaw, Spyderco, Benchmade, Cold Steel, CRKT, and KABAR? How much extra equipment or labor would be needed to make mass-produced versions of grinds favored by Wilson, Johnston, Boye, and Landes? Would consumers pay the extra cost for extra performance? Just because we buy knives made of S30V or whatever the next S30V is named in no way suggests we (including me) will pay for increased performance.

I don't see why any of this has to lead to the arguments we see here. There are knives which function better with S30V and knives which function better with 13C26 and cases where round pegs have been sheered into square holes in terms of alloy choices, but physical inventory and customer demand explain those occurrences more easily than most other explanations. If some product doesn't work for you; get or make something else.

*By surprize, I mean Steve's 64.5RC Storm II wouldn't form a polished edge for me no matter what I did. In contrast, Kershaw's SG-2 and Spyderco's ZDP-189 at similar hardnesses and with much higher amounts of carbides (and larger carbides at that), easily polish up to scary sharp.

 

[db]

Yeah you have, I have the emails from the testors. You are lying directly. You want me to post the emails where they say directly you placed restrictions on them.

WOW! Who would be dumb enough to discuss the terms of Kershaws testing, with Cliff given the history between him and Thomas?

 

[Larrin]

Landes has about one or so at 1050C, Verhoeven is likely close to 1100 C. These numbers though are averages, you really have to be careful when citing them to not quote them as if they were meaningful to that precision. They really are not significant in terms of microns.

Spot checks on the microstructure in the same steel would never be that close together, you can see this from Landes micrographs if you just imagine quarter panel individual averages. The CI's would be much larger than a micron.

You can also estimate the size directly from the razor blade paper I sent awhile back which gives the retain primary carbide volume because you would expect the size to be proportional.

What I find rather interesting is that 13C26 is near ideal for a razor blade steel (promoted anyway). It would seem logical to just eliminate the primary Cr carbides completely by taking something on the carbon saturation line and just increasing the C content to get maximum hardness. Of course this reduces stainlessness which is important for actual razors so it might be that 13C26 hits a total sweet spot.

It however does raise the point about nonshaving uses, I don't see why 13C26 would be above carbon steels which have much finer carbides (Cr carbides are huge in comparison to cementite) so it would seem something like 1095 (with less C) would be ideal, maybe with tungsten or similar for grain refinement, i.e., F2 or similar. Hopefully Landes will discuss this in more detail in his next book.

-Cliff

I don't think Verhoevens' micrograph looks any different, at least not far off, from .6 of a micron. Landes measures a couple of the larger carbides, but does not give an average. I do not feel bad about using this average. Verehoven himself looked at carbide volume with multiple austenitizing temperatures, and there is no indication that he didn't take the average size from looking at multiple micrographs rather than a single one. An average is still and average.

It's impossible to eliminate primary carbide, because it is of course the carbide that forms in the initial melt. However, Sandvik claims that they eliminate all primary carbide in the forging process in all alloys but 19C27, and Verhoeven says that primary carbide was not observed in AEB-L. Landes has also given no indication that any primary carbides are present in AEB-L. The forging process of Sandvik and Uddeholm appears to be superior to the convential, as can be seen by the micrographs of the X65Cr13 steel here: http://www.metallograf.de/start-eng.htm

If you followed the carbon saturation line, there wouldn't be any carbide at 2012F, not just a lack of primary carbide. If you raised the carbon saturation line to a higher temperature, then you could have more carbon and chromium for more carbide volume, but the austenitizing temperatures would be raised for full hardness. However, there is a point where the theoretical is beaten out by the real world, where primary carbide would not be eliminated through forging. Also, it is possible that grain growth could occur because of the need for higher austenitizing temperatures. The carbide volume is already quite low for AEB-L and 13C26, I wouldn't want it to be any lower by lowering the carbon to the point of the cabon saturation line at 2012F.

It is my opinion that AEB-L has hit the "sweet spot." It has 11-12% chromium in solution after heat treatment (depending on austenitizing temperature), it reaches a hardness of at least 63 Rc, it has very tiny carbides, no primary carbides, etc. There are steels with more wear resistance, but none with the combination of hardness, toughness, corrosion resistance, and carbide size that AEB-L has.

AEB-L's chromium carbides aren't any larger than the cementite I have seen in micrographs. Verhoeven has a micrograph of 52100 that has received the standard heat treatment (1550F austenitizing temperature), and the largest carbides appear to be around 1 micron, which is certainly no finer thant he carbides in AEB-L, and the micrographs for carbon steels in Landes' book don't look any finer than 1 micron, they look larger to me. The micrograph of O1 shows that most of its carbides are about the same size, but many are clumped together in to comewhat larger carbides in the rolling direction, where AEB-L seems to have more evenly distributed carbides. The carbides in F2 are about 2-4 micron according to Landes.

Edit: In the back of his book, Landes goes over the properties of the steels, as you know, and shows AEB-L having the highest possible in all of the categories related to edge stability. The reason it has the highest is because the carbides are as small or smaller than the other carbon steels in the book, added to the fact that it can reach a high hardness, plus that it uses the harder chromium carbides. The harder chromium carbides means that AEB-L is more wear resistant than even 52100, which can be seen in Verhoeven's CATRA testing on 52100, 1086, Wootz, and AEB-L. I was going to send you this, but I haven't looked forward to scanning it.

 

[thombrogan]

Dog of War,

Any new findings with your Junk Yard Dog II?

 

[Dog of War]

Dog of War,

Any new findings with your Junk Yard Dog II?

Not yet, but I hope to have some more in the works soon: longer test runs on rope, then some testing on cardboard. FWIW when doing these tests I'm actually testing some other blades not mentioned here to satisfy personal curiosity, making it more time-consuming than it might seem.

Also wanted to tell you how much I appreciate your contribution to this thread, Thom, it sounds like you've done a great deal of work with this steel. Yours and others experiences all seem to be amplifying the same positives I'm seeing. Particularly wanted to mention this statement:

For the knife user used to S30V tactikewl stuff, it's an upgrade with a lower price.

Everything I've seen leads me to agree fully with this conclusion, even though my own work to this point doesn't seem sufficient for me to say that independently, not yet anyway. IMO this is pretty huge, considering what a big deal S30V has been in the knife industry since its introduction. The main benefit I've personally gotten from S30V is it's made me really appreciate fine grained, high edge stability steels ... and 13C26 seems like the ne plus ultra for that.

BTW, Larrin - I didn't realize you were Devin's son ... no wonder I find myself in awe of your knowledge! You're a big asset to these forums.

 

[Thomas W]

Cliff I was going to go off on a run like in the past, but have come to the same conclusion of STR, your just not worth it. Sorry to take all your fun away.

Yeah you have, I have the emails from the testors. You are lying directly. You want me to post the emails where they say directly you placed restrictions on them.

Cliff your ass should be banned for names and threats like these. May shame come on you! I will also caution you from calling me a liar ever again, there is no place on any forum for that.

The restrictions that have Cliff upset are the fact that I shut him down from being involved with the testing, and the testers needed to keep the results private. The tests were for Kershaw's benefit, and not for public consumption.
Cliff got his little feelings hurt cause he thought he was going to get in the backdoor with the testing, and it got pulled from him last minute.
Since these tests have been finished STR has posted the results (this was all based on the higher hardness (64.5 Rc) 13C26). There were no performance or testing restrictions put on the individuals.
Grow up Cliff!

 

[STR]

Thomas the only thing Cliff could be referring to from me in the way of an exchange would be his take that field testers not being able to go public with results is what he calls a restriction. I personally understood this with prototypes and knives not yet available to the public because it only makes sense in my mind. I mean what if the knife we are testing doesn't make the grade? Do other companies publish the results of their private tests on prototypes and new non production knives?

For what its worth, this is the only thing I recall ever telling him if I am one of the 'testers' he refers to. I'm sure it was something to that effect. As I recall it was around the time we were discussing not having Cliff see the knives you sent and his not being interested in contributing anyway if he could not publish the results on his web site.

For the record as Thomas stated you can see reviews of current production knives I did make results public on and while I don't have the links they should be readily available to a search button.

STR

 

[Thomas W]

Cliff test it out for yourself or don't comment about what you haven't done and can't personally testify to.

The problem with this now, is that nobody could take Cliff's test seriously because he has shown himself to biased in this case. We would all have to wonder about the accuracies vs Cliff wanting to show himself to be right.

 

[Larrin]

BTW, Larrin - I didn't realize you were Devin's son ... no wonder I find myself in awe of your knowledge! You're a big asset to these forums.

Thank you.

 

[Dog of War]

Well , since I unwittingly started this thread that turned into a catalyst for all this ....

.... You want me to post the emails where they say directly you placed restrictions on them.

Cliff, you should know as well as anyone, this is Netizenship 101: Things said in email between forum members are understood not to be for later posting -- that's the reason why they were emailed and not posted on the forums to begin with.

Not only have you really stepped in it, apparently you've decided it's OK to compromise people who trusted you in doing it. Who knows how wide a net of distrust this could cast, including people who've had nothing to do with this at all?

Honestly, Cliff, if I see "Banned by Moderators" under your name next time I visit here, it won't surprise me one bit.

Thomas W - let me first say, I think you've got a terrific product in this JYD2. Hopefully that somehow makes all this other stuff that's gone on seem not so bad.

I also want to say, putting myself in your shoes and seeing what's unfolded here, it concerns me that this could sour you on the forums, and make you think twice before involving anyone from the forums in future testing.

I have no idea what all has gone on behind the scenes, who's involved (if anyone) and what was said, who said what to who, etc. But I do see the intelligent input you've gotten back from guys like Thom and STR, and there's no doubt in my mind that soliciting opinions and involving enthusiasts like you have is a good deal all around: good for Kershaw, and I'm sure it's a lot of fun for the unpaid field testers themselves.

I just hope you don't think less of the BFC forum community because of all this. I've seen the way you handle people with product issues, your communications about developments out of Kershaw, and your involvement in the discussions, and I think you're a class guy and reflect well on Kershaw. I'd hate to see you pull back from what you've been doing and from involving BFC members like you have in your product testing and development.

 

[Dog of War]

Thank you.

You're very welcome. And thank you for the kind remarks on my review.

 

[db]

I'd like to second every thing DOW has said in his post 56. Even though I can b a pain in the butt to some I shurely wouldn't want anyone to not feel welcome here from something I have posted, even Cliff. Thomas your doing good.
I think I'm going to have to get me some of this 13C stuff pretty soon
And good review DOW looking forward to more of it.

 

[fishtale]

I really like the Kai Kershaw direction. The collaborations are fantastic. I've had a Chive for years and it's been great. I will be getting a Storm this week to see what all the fuss is about. Keep up the good work!

 

[msiley]

I just ordred a Leek in 13C26. I'm dying to test this guy out.
Not sure if I'll have time for a full review.... I'm in
grad school and the homework has reduced my knife quality time.