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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 12:50 am 

Joined: Tue May 29, 2012 12:29 am
Posts: 917
5 degrees per side? You would be regrinding the side of the knife at that angle. Your sharpened angle is not measured from the side of the knife but the center of the apex. Even at extreme low angles (say a penny high) your only getting into the 10 degree per side range. Most people that freehand sharpen do so at much higher angles than they think.

Burnt edges from the factory are a HUGE line of BS and paranoia. It might happen in some cases but I would bet its much less often that some portray it to be. When you sharpen a few hundred knives a day you don't make that many mistakes.

For AEB-L I found that 28 inclusive was its limit, below that and the edge acts like tin foil. This was measured with a CATRA laser protractor. To get the extreme angles your are trying to get you will need to look for steels @ 62+ Hrc otherwise the edge stability will be too low to support it.

I would also say your sharpening is part of the problem, you might be able to get your edges sharp but there's more to it than that. I've sharpened thousands of knives from more makers than I can name and the problems you describe sound more like sharpening problems than anything else. Try backing the finish down to 3k-5k too and you will find the edge to last much longer.


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 1:15 am 

Joined: Sun Jan 12, 2014 9:30 pm
Posts: 7
Jason B. wrote:For AEB-L I found that 28 inclusive was its limit, below that and the edge acts like tin foil. This was measured with a CATRA laser protractor. To get the extreme angles your are trying to get you will need to look for steels @ 62+ Hrc otherwise the edge stability will be too low to support it.


I feel like 90% of my post is being ignored, for example where the knives are being out-performed by some fairly generic and low performance cutlery, and you're focusing on the single experiment I performed where I sharpened the knife to 10 degrees inclusive. I have sharpened the knife to apex angles like you're suggesting, and at those angles the performance was simply poor. Should I expect that I can sharpen and run a Wusthof Classic and a Richmond Artifex both at 30 degrees inclusive on the exact same fixed angle sharpening jig system, perform the same work with them side by side, and see significantly better edge retention from the Wusthof? Because if that is the case, and Mark confirms that is the expected behavior, then really all my questions but for the original one have been answered and I can leave this discussion. :)


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 1:36 am 

Joined: Tue May 29, 2012 12:29 am
Posts: 917
I wouldn't say 90% but a lot of the things said just don't jive.

So what other angles are we talking about? Your highest angle spoke of is only 30 inclusive and that is getting to the extremes with most cutlery. You repeatedly talk about 5 and 10 degrees per side which is far too extreme for most any cutting edge.


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 1:53 am 

Joined: Sun Jan 12, 2014 9:30 pm
Posts: 7
Jason B. wrote:I wouldn't say 90% but a lot of the things said just don't jive.

So what other angles are we talking about? Your highest angle spoke of is only 30 inclusive and that is getting to the extremes with most cutlery. You repeatedly talk about 5 and 10 degrees per side which is far too extreme for most any cutting edge.



Actually I'm afraid to be the one to break it to you, but 30 degrees inclusive is hardly extreme. What angle do you think you sharpen a razor at then? Do you think if you took a straight razor and cut thin plastic with it, it would also experience this sort of failure?

Straight razors hover around 8 degrees inclusive depending on the blade for the record. Implicitly then you're saying yes you do expect this behavior from a straight razor. If you concur, this is an easily falsifiable statement. You can replicate the experiment with a straight razor, or tear apart a disposable razor, measure its angle, and repeat the experiment with that. That is the basis of a good scientific experiment, the ability for an experiment to be replicated/falsified.

Let me ask you though:
If you truly believe there is no reason to ever sharpen cutlery more acutely than 30 degrees inclusive, why would you see a role for steels like AEB-L in kitchenware at all (beyond low grade cutlery obviously) when there are so many high carbide volume steels which will significantly out-perform it at that geometry?


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 2:30 am 

Joined: Thu May 24, 2012 6:20 am
Posts: 1824
Hunter,

Your original question pertained to the Tanaka Ginsan 210mm gyuto and its comparative performance to the Richmond Artifex.

As you are aware the Artifex is manufactured by Lamson and Goodnow using AEB-L steel (http://www.zknives.com/knives/steels/aeb-l.shtml). The Tanaka is a different manufacturer using a different steel, Ginsan steel (http://www.zknives.com/knives/steels/ginsan.shtml). Since the manufacturing processes differ, the quality control differs, and the performance envelope of the materials differ, I would not expect that the shortfalls of the Artifex should specifically bias your assessment of the Tanaka product. That said, the Tanaka it is a relatively new knife to CKTG so does not have a significant track record yet. It has been well reviewed by some, but I doubt they have as exhaustively tested their knife in the manner you have tested your Artifex.

Some of the limits of the Artifex are well chronicled here, certainly 5° inclusive is a newly established limit.

Best of luck finding a knife that meets your expectations.


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 3:11 am 

Joined: Sun Jan 12, 2014 9:30 pm
Posts: 7
Thank you very much cedarhouse for addressing my original inquiry.

Please don't misunderstand, I had no intention of implying that their visually similar chemistries would inherently create comparable performance, although for what its worth I suspect that slight carbon increase in the Ginsan will have more effect than one might initially think.

At the moment I find myself bouncing between several possibilities. The Tanaka product, while minimally reviewed, does have some public review and (clearly) the modifications to it necessary for use don't phase me. Stylistically it is very much in line with my tastes, although I consider that secondary. In contrast, the other knife I'm considering, is one of the Seto gyutos which has a single endorsement, but that one is quite significant. Beyond that though it has no real public review I can dig up, and precious little pertinent information. It also happens to have a minor carbide volume steel, which reduces edge stability. (obviously most of these stainless knives can be heat treated such that some of their carbon sucks chromium out of solution and forms nasty chromium carbides cutting stain resistance and edge stability for wear resistance) As a secondary gripe, it also isn't stylistically as in-line with my tastes as other options. *shrug* I'm sure, regardless, I'll survive until I can dig up a favorite. :P

Thanks again.


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 3:15 am 

Joined: Thu May 24, 2012 6:20 am
Posts: 1824
As many here can attest, demanding standards are hard to meet :D


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 4:05 am 
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Joined: Thu Nov 22, 2012 4:17 am
Posts: 4207
Hunterseeker5, Wecolme to the forum.
Hunterseeker5 wrote:.....Okay, hand grind any of the potentially damaged steel off, and apply a fresh apex. I did this, leaving the knife with a beautiful high finish (something like 10K grit) at 10 degrees inclusive. My next culinary exploit was twin nested stuffed pork loins, so I found myself cutting that thin plastic vacuum packaging you find frequently on cured meats. This resulted in visible deformation to the apex up to .5mm deep, and further rippling above this. Clearly this is not an acceptable behavior for a knife. I continued to use it anyway, just to see if the issues extended through the entire blade rather than just at the tip, and after about 4 onions, a red pepper, some raw meat (boneless), and some mushrooms the edge had been completely ruined; there was visible damage, I didn't scope it to see if it was entirely deformation or if there were fractures as well, along its entire length.


10 degree inclusive freehanding, I SERIOUSLY doubt it. But for the sake of argument lets say OK. In your own words you did a lot more than just open a plastic bag to trash the edge. I would expect any knife with a 10 inclusive edge to fail under these conditions. And before you go repeating the same babble about razors and crap, we are talking about kitchen knives. Disposable razors and straight razors alike are totally different animals for completely different purposes. Different steel qualities, different steel types, heat treatments, fabrcations, and on and on. You need to compare apples to apples.

I don't believe you have put a 10 degree inclusive edge on any kitchen knife and it performed well. You would have to show me a video measuring the angle and then you using the knife to get me to believe that. Sorry for the skepticism but as Jason said, this story just doesn't add up.
Enjoying the conversation though. Maybe I'm wrong and will learn something, you never know!



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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 4:11 am 

Joined: Tue May 29, 2012 12:29 am
Posts: 917
Once you reach 30 inclusive you start a decline in edge stability, for some steels this is a breaking point and the edge starts acting like foil deforming and crushing under the pressure of the cut. Cutting copy paper would be one way to test edge durability, it will quickly burr the edge if to thin.

A properly sharpened straight razor would be damaged by cutting copy paper just like a yanagi sharpened to thin. There is nothing wrong with the steel its just reached its limits and its uses become very specialized. Your also not factoring in actual hardness which can vary widely regardless of stated numbers. Basically, your asking a lot from a production knife and you will find very few premium knives that can perform with single digit bevel angles.

The bevel angle is also not as large of a factor as the behind the bevel thickness and overall geometry of the blade.

I never said there is no reason to sharpen below 30 inclusive but I will say that at angles of 30 inclusive and below the edge of the cutting tool becomes increasingly specialized to the cutting task.


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 Post subject: Re: Artifex performance issues
PostPosted: Mon Jan 13, 2014 5:12 am 

Joined: Sun Jan 12, 2014 9:30 pm
Posts: 7
Jeff B wrote:Hunterseeker5, Wecolme to the forum.
Hunterseeker5 wrote:.....Okay, hand grind any of the potentially damaged steel off, and apply a fresh apex. I did this, leaving the knife with a beautiful high finish (something like 10K grit) at 10 degrees inclusive. My next culinary exploit was twin nested stuffed pork loins, so I found myself cutting that thin plastic vacuum packaging you find frequently on cured meats. This resulted in visible deformation to the apex up to .5mm deep, and further rippling above this. Clearly this is not an acceptable behavior for a knife. I continued to use it anyway, just to see if the issues extended through the entire blade rather than just at the tip, and after about 4 onions, a red pepper, some raw meat (boneless), and some mushrooms the edge had been completely ruined; there was visible damage, I didn't scope it to see if it was entirely deformation or if there were fractures as well, along its entire length.


10 degree inclusive freehanding, I SERIOUSLY doubt it. But for the sake of argument lets say OK. In your own words you did a lot more than just open a plastic bag to trash the edge. I would expect any knife with a 10 inclusive edge to fail under these conditions. And before you go repeating the same babble about razors and crap, we are talking about kitchen knives. Disposable razors and straight razors alike are totally different animals for completely different purposes. Different steel qualities, different steel types, heat treatments, fabrcations, and on and on. You need to compare apples to apples.

I don't believe you have put a 10 degree inclusive edge on any kitchen knife and it performed well. You would have to show me a video measuring the angle and then you using the knife to get me to believe that. Sorry for the skepticism but as Jason said, this story just doesn't add up.
Enjoying the conversation though. Maybe I'm wrong and will learn something, you never know!


First off, I didn't say I applied the 10 degrees inclusive apex by hand, I said I reground it by hand (actually at a lower angle, but thats not the point) then apexed it. Not sure why that is so implausible to you though, because straight razors are almost exclusively hand ground and its quite frankly not that difficult. (try it some time, seriously)

A few things regarding the "plastic bag." First, I saw the damage prior to trashing the edge on those vicious veggies.

I bolded this, but I thought it merited quoting again:
"Disposable razors and straight razors alike are totally different animals for completely different purposes. Different steel qualities, different steel types, heat treatments, fabrcations, and on and on."
In this case most of all, this is actually definitively incorrect. AEB-L is SPECIFICALLY a razor blade steel, and if you read the description on the knife even Richmond alludes to this. I'll even save you the trouble of looking it up for yourself:
"AEB-L (also called 13C26) steel was designed for razors, which need corrosion resistance, high hardness and very acute edges."
ref. http://www.chefknivestogo.com/arexta24gy.html
Furthermore, Mark specifically alludes to the qualities of these razors as being the reason why this steel was chosen. Again your assertion that these two types of blades would have completely divergent mandates and production protocols on this same steel because they require different end-line properties is definitively false. They both require high edge stability and fine grain structure at moderately high hardness to achieve high sharpness fine edge retention for the purposes of fine cutting. Keratin, also, isn't particularly easy to cut, significantly more of an obstacle per unit thickness than a "plastic bag" for example.

I didn't actually say whether or not I had put a 10 degree inclusive edge on another kitchen knife and it performed well. Whether or not I did, in this case, is a bit immaterial. Your comments though on your perceived divergence between these two classes of cutlery on the same steel does beg a question though: do you expect the razor blade to perform better or worse at 10 degrees cutting thin plastic than the Artifex? If you expect it to perform worse, I suspect you'll be disappointed as it would fail to shave you effectively for any real period if it did. If you expect it to perform better, I'm curious as to why you think the properties which would cause it to be superior in this regard would not be well suited for a kitchen knife?

Finally, please don't degrade yourself and this argument to the "prove it" level. Nobody has ever "proven" anything on the internet, it just bounces from one "I don't believe it" to another "I couldn't see what you did there in that video" and finally "you faked it." If you're unwilling to accept my observations, to the point of "prove it" as opposed to constructive experimentation, then really this conversation between us has come to an end because it is neither my goal to personally convince you of my observations nor is it productive.

Jason B. wrote:Once you reach 30 inclusive you start a decline in edge stability, for some steels this is a breaking point and the edge starts acting like foil deforming and crushing under the pressure of the cut. Cutting copy paper would be one way to test edge durability, it will quickly burr the edge if to thin.

A properly sharpened straight razor would be damaged by cutting copy paper just like a yanagi sharpened to thin. There is nothing wrong with the steel its just reached its limits and its uses become very specialized. Your also not factoring in actual hardness which can vary widely regardless of stated numbers. Basically, your asking a lot from a production knife and you will find very few premium knives that can perform with single digit bevel angles.

The bevel angle is also not as large of a factor as the behind the bevel thickness and overall geometry of the blade.

I never said there is no reason to sharpen below 30 inclusive but I will say that at angles of 30 inclusive and below the edge of the cutting tool becomes increasingly specialized to the cutting task.


Fascinating. So, having sharpened thousands of knives by your own claim, you're unable to achieve an apex geometry below 30 degrees on SOME of them which will not fall apart like foil. Since I assume you do accept the physics fundamentals which higher apex angles are sharper and thus cut better, would you not then logically conclude the fraction of the knives you've worked on which can sustain this more acute geometry are superior? Food for thought.

I'm also rather surprised that, in all your sharpening, you've never come across a knife with more acute apex geometry than 30 degrees. So called "scandi ground" knives essentially all have more acute apex geometries than 30 degrees inclusive. Moras are one of my favorite examples of this, and their stainless variants use 12c27 (ref. http://en.wikipedia.org/wiki/Mora_knife) which is a close relative of 13c26 AKA AEB-L. While you may argue that they may be apexed from the factor with a hint of micro-bevel, they're resharpened by their rabid fans (and myself) on a zero grind at about 20 degrees inclusive IIRC. I would be interested to hear your comments on why this vastly less expensive, dare I say cheap, knife is able to sustain things your probably more expensive knives can not? Would not a Mora sharpened to 20 degrees inclusive for an apex but given a full height grind above that then out-perform the knives you sharpen so long as its wear resistance maintained the edge? Food for thought.

"you will find very few premium knives that can perform with single digit bevel angles."
So what about a cheap knife then? Knock less than 1 degree off the apex angle of a Mora, and you're into single digit bevel angles with extremely well documented strong performance. It also happens to be convenient that the steel is relatively comparable and that the price is rock bottom, so no claims of unfair play regarding "higher end" processing funded by astronomical prices.

"A properly sharpened straight razor would be damaged by cutting copy paper just like a yanagi sharpened to thin."
This is an interesting assertion. I'm sure you could improperly sharpen, or find a low grade, straight razor which would be damaged by cutting paper. A decent straight razor however will not be damaged, merely dulled, as the edge will neither catastrophically collapse nor fracture. Its an interesting reference though, because there is a significant difference between the plastic I was referencing causing significant damage to the Artifex and a piece of paper. Plastics are highly refined, and in this case highly homogeneous; their hardness is throughout, containing no particulates. Paper, by contrast, is non-homogeneous being highly fibrous, containing a grain structure, and also hard particulates such as silica. Individual cellulose fibers also must be cut, and have significantly higher tensile strength (individually) than the homogeneous plastic I cut. I did not test this knife on paper, I didn't originally intend to "test" it on plastic either because quite frankly I was shocked that it ended up being a "test" at all.

"The bevel angle is also not as large of a factor as the behind the bevel thickness and overall geometry of the blade."
A very interesting assertion. You could attempt to argue that it is, to an extent, substrate dependent and you would be correct, but to ignore apex angle would be to essentially cut sharpness out of the equation in its entirety. Just as an example, since we're enjoying talking about razors at the moment, I would invite you to sharpen one of your straight razors (or any knife) to 30 degrees and shave with it. When you've recovered from that bout of what I can only imagine will be shaving irritation of biblical proportions, you can then revisit it with a blade at 10 degrees or less. To move away from shaving, and into the abstract, the main factors regarding the relevance of above-apex-thickness are material rigidity and thickness. I don't think I need to elaborate on this, as its rather self evident, am I right? There is no escaping though that sharpness is fundamentally defined by the thickness (we're talking on the sub-micron scale now) of the apex and its angle. Extending this, what if you were to have a knife with no bevel at all, it were able to go straight to the edge. (zero ground) Would that not be considered superior even by your own definition?

Because I have the suspicion you'll arbitrarily reject the Mora, how about another example? This example is rather controversial, as it is a bit of a misapplication of steel/technology and more proximately they had grinding damage resulting in blade failure in the initial production run (yes that rare thing that nobody ever does because they do it all day long) but here is a knife with no apex bevel:
http://www.spyderco.com/catalog/details.php?product=780

So a significantly larger grain and lower edge stability steel ground without an apex bevel to sub 10 degrees inclusive able to do everything the Artifex can not, and from a highly reputable brand. Welcome to a larger world of cutlery. I want to reiterate, just quickly, that S30v possessing large chromium carbides and thus significantly lower edge stability than AEB-L (properly applied of course) is able to do this, and be manufactured in a production environment.

*edit*
BTW Jeff B, I apologize, but I'm finding your signature supremely ironic at the moment:
"Those who say it can't be done are always passed by those doing it."


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