TDG: The Way Of The Knife

[Mottmott]

Chad, You've inspired me. I have an couple 30-40 year old (tatty looking but very sharp) carbon steel Sabatier's (8 & 10") and a 7" carbon Henkels. I'm going to get out the Dremel and customize them! Why not make a good thing better? A few years back I bought a Wustof chef's knife and wound up giving it away. Too thick, too wide, too heavy, and too hard to keep sharp. And, I had trouble getting used to that rocking action.

I'm also going to work on a cheap carbon steel Chinese half cleaver that's actually the sharpest blade I've ever had, but so thin its edge has become somewhat serrated!

Edited December 29, 2003 by Mottmott (log)

[Mottmott]

I have a couple questions.

Chad, the technical alpha-numeric descriptions of the steel in these catalogs whizzz over my head. Is your Mullin blade what I call carbon steel? - The sort that's likely to stain? Do I understand correctly that you have Mullins's 8" blade unmodified? Or did you have it modified? Yours looks a little shallower than the blade on his website.

And I'm curious what is "cast dendridic steel" ?

[Chad]

I have a couple questions.

Chad, the technical alpha-numeric descriptions of the steel in these catalogs whizzz over my head.  Is your Mullin blade what I call carbon steel? - The sort that's likely to stain? Do I understand correctly that you have  Mullins's 8" blade unmodified?  Or did you have it modified? Yours looks a little shallower than the blade on his website.

And I'm curious what is "cast dendridic steel" ?

Mottmott, thanks for the kind words! I appreciate it.

The nomenclature for steel designations can be bizarre and Byzantine. The best reference (outside of a metallurgy text) is Joe Talmadge's Steel FAQ. This authorotative FAQ was recently updated and should answer any questions you might have.

In short, though, no; ATS-34 is not carbon steel. It is a high-tensile-strength stainless steel. It has recently been surpassed by newer super steels such as BG-42 and CPM S30V, both of which are tougher, stronger and generally much hipper. However, since ATS-34 (CPM 154 in the American version) has fallen slightly out of favor it can be found at much lower prices than the super-steel du jour.

The general rule of thumb is that if a steel contains more than 12-13% chromium, it is "stainless." This is not necessarily true. For example, D2 steel has about 12% chromium, but I'd never think of it as stainless steel. It is a hell of a steel, however. Likewise, ATS-34 has many wonderful properties. Absolute stainlessness isn't one of them. It'll take a patina. I just don't worry about it too much. The other attributes of the steel -- strength, toughness, wear resistance, etc. -- far outweigh any aesthetic considerations. You might take at look at the eGullet Knife Maintenance & Sharpening Tutorial for more information about steels, their properties and how to keep your knives in top shape.

I've modified my Mullin/Pack River chef's knife heavily. I've hot-rodded the edge, rounded the spine and reshaped the handle -- all of the mods mentioned in "The Way of the Knife" were done to the Mullin knife. All done in my garage with high-grit sandpaper, a Dremel tool and a basic sharpening rig. Of course I started with an exceptional knife, so it wasn't hard to customize it to my particular needs. The mods are not particularly noticeable, however, so any difference between what's on Steve's website and the pictures in my article are probably due more to camera angle than they are to actual differences in blade width.

As for "cast dendtritic" steel, that's something that knifemaker David Boye came up with. It is a way of pouring molten steel so that the carbides form "dendrites," tendrils or links between one another, reinforcing the strength of the steel and seriously increasing its cutting ability. I have to admit, I'm not up on the science of how it works. I do know, however, that many knife nuts I respect are blown away by the cutting ability of cast dendritic knives. You might ask slkinsey about his dendritic knives. Sam is very knowledgeable about materials science and might be able to give you a more complete answer.

Chad

[slkinsey]

"Dendridic" steel is steel that is cast rather than forged. This provides certain desirable properties.

Steel, fundamentally, is a bunch of carbide crystals held in a matrix of iron. The carbide crystals stick out on the edge and are what give a blade its actual cutting power. If you look at a polished blade edge under a microscope you will notice that it still looks like a saw. The carbide crystals are the "teeth" of the saw.

Forging steel, among other things, involves banging on the hot steel with a hammer. This has the effect of breaking up the carbide crystals and making them smaller. Forged steel with smaller carbide crystals is said to have a finer "grain size." So, if one has a blade made with a steel that has a very fine grain size, the "teeth of the saw" will be smaller -- is a very valuable property in certain applications. It is very good at "push cutting" (cutting something with no side-to-side motion of the blade) and it does very little tissue damage. This is why one would like to use a forged steel with a very fine grain size for a scalpel or a razor.

One disadvantage of forged steel with a very fine grain size is that the edge dulle fairly easily. This is because the primary way a steel edge becomes truly dull (as opposed to simply needing to be straightened on a steel) is by having the carbide crystals that form the "teeth of the saw" pop out of the iron matrix. The smaller the grain size is, the weaker the iron matrix's grip is on each individual carbide particle and thus the greater the probability that the particles will pop off of the edge.

Dendritic steel is made an entirely different way. David Boye, the modern-day pioneer in this kind of steel, started thinking about fine-grained forged steel and asked: "who cares about minimal tissue damage and clean push-cutting ability when you're cutting up a chicken?" The answer is, well... no one really. Certainly not the chicken.

So, what Boye did was to make steel that was not forged at all. Instead, it is cast in blade-shaped molds. When the steel cools, the carbide forms in a large network of interlocking crystals throughout the steel. Since the steel is never forged (i.e., never beaten with a hammer) the carbide crystals stay very large. This has several benefits: First, since the carbide crystals are very large, the "teeth on the saw" are also very large. This gives dendridic steel blades what knife fans call an "aggressive edge" -- which is a fancy way of saying that it will cut the crap out of anything you drag it across with a sawing motion (as opposed to a push-cut motion). One can somewhat mimic this effect with a forged steel blade by sharpening with a course grit, but it's not really the same thing. Second, since the carbide crystals are so large, the iron matrix has a very firm grip on them, and since the crystals are embedded in a network of interlocking carbode crystals, they all have a very firm grip on each other. The result is that the carbide crystals at the edge are very resistant to popping off. The result of that is that the edge stays sharp for a very, very long time. When I was deciding which knives to buy, I tested the dendridic steel knives against a variety of forged steel knives for edge retention (cut a 1" piece of hemp rope and counted how many cuts it took to dull the blade). The dendridic blades retained a keen edge something 300% longer than the forged blades.

[AzRaeL]

pity no picture to accompany the text

i'd love to see what that knife looks like

[Chad]

Scroll up a little ways. Sam has posted a shot of his Boye-cast chef's knife. As I understand it, David Boye supplied the cast blank and another knife maker finish-ground the knife and added the handle slab. I hope I have that right. Sam can add the details. It is a f*ing gorgeous knife. From Sam's reports and the intel I have from other knife nuts, cast dendritic is indeed the shiznit. Boye's stuff has increased in value exponentially the last couple of years. There is a serious aftermarket trading scene centered around his knives. Go to Boye Knives Gallery to take a look.

Chad

[Mottmott]

Thanks to both of you for the explanation. The cast dendritic blade sounds amazing, but a tad pricier than my amateur status probably justifies. Though I'm open to argument. Less sharpening by a factor of 300!

I'm still enamoured with old fashioned carbon steel that is, at least, easily sharpened. I'm not averse to a new knife, but my typical experience with "new" and "better" technology is that it often has as much down as upside. I shake my head at the idea of a knife with a metal handle or a ceramic, breakable when dropped blade!

Stainless knives look cleaner than my darkened and, yes, I admit it, pitted, 8" Sabatier, but I didn't find the Wusthof version of stainless cuts better or keeps sharp easier. I suppose, though, that mass market knives probably don't use the same quality metal as the artisan made knives.

AzRael, look above for the photos. And for real culinary tool porn, check out the websites listed by Chad.

Barbara

Edited December 29, 2003 by Mottmott (log)

[AzRaeL]

I'm still enamoured with old fashioned carbon steel that is, at least, easily sharpened. I'm not averse to a new knife, but my typical experience with "new" and "better" technology is that it often has as much down as upside. I shake my head at the idea of a knife with a metal handle or a ceramic, breakable when dropped blade!

i bought a ceramic blade out of curiousity. A good old Kyocera ergonomic.

it was VERY VERY Sharp but feels odd to handle. Feels like it has to be pampered and mollycoddled and it doesn't stick to my magnetic bar.

It wasn't cheap either. It does its job but it does not inspire confidence.

I'm just gonna use it for now. My S.O. is soooo gonna bug the shit out of me (to put it mildly) if I blow more money away on knives.

my next blade planned is a 24cm Drop Forged Global Chef's Knife.

Sure i'd love a custom blade but i can't afford it for now.

[slkinsey]

Thanks to both of you for the explanation. The cast dendritic blade sounds amazing, but a tad pricier than my amateur status probably justifies. Though I'm open to argument. Less sharpening by a factor of 300!

Well, less sharpening by a factor of three. The one drawback is that dendridic steel is very hard and as a result sharpening is quite a bit more difficult.

As for the price... Boye's knives are very expensive. But this is mostly because they are "art knives" with all kinds of fancy images etched onto the side. I doubt many of them are actually used as working knives. When I got my knives (and Chad is correct: Boye provided the knife blanks and my knifemaker did all the rest), they didn't cost all that much more than a comparable Wusthof. They're probably a bit more than that, but certainly not up at the huge prices Boye's knives command. From what I have been able to tell. my guy has left the custom kitchen knife business and is making blades for chicken processing plants, etc. But it's possible he still does the occasional custom kitchen knife. I'll shoot him an email if a number of eGulleters think they'd be interested.

Perhaps we can comission a bulk order of "eGullet Specials" from him, or from another custom knife maker. Might be cool, and we could probably get a deal if we made an order of, say, twenty 10" chef's knives. I want one of those big-ass Tichbourne "Chinese cleavers" myself.

[CRUZMISL]

Sam, count me in if you do the group thing. Sounds like fun.

Joe

[AzRaeL]

AzRael, look above for the photos. And for real culinary tool porn, check out the websites listed by Chad.

oh man! hahaha

my crap computer at work didn't display the knives for some stupid reason.

bah..WindowsXP

now i'm at home..i see the knife clear as day

[budrichard]

I wish I could post a picture of my Japanese Honyaki(no file attachments option), handforged by Kenichi Shiraki from Hitachi White #1 steel with double side mirror finish. Murray Carter acted as the agent in the comissioning of this knife. even though Murray produces knives of this type, I wanted the best from an individual Japanese smith, the kind of item that never gets out of Japan. Since Murray works and lives in Japan, he was good enough to help. The handle is ebony with ivory inserts as is the scabbard.

I have been collecting custom knives for 30+ years and I do have a few custom kitchen blades and carving sets. Comparing blades is certainly subjective with the methods that most of use. The Kenichi Honyaki is not much sharper if at all than my commercial Sashimi knife. What it is, is a finely crafted knife forged by a single craftsman in a time honored tradition and that is what i appreciate it for.

Since i use so many different blades and look for uniformity when going from blade to blade, i have standardized on Wusthof for most of kitchen blades because the knives are uniformly good, come in a vast array of sizes that i can get to fit my hand and the different types of blades offer the larget selection to choose from that I know of.

All of the makers referenced here produce excellent blades. One that i would like to point out in particular is Bob Dozier. His blades are the sharpest non forged knives I have ever used. His D2 steel takes a wicked sharp edge, what I term Dozier Sharp. In fact i will not let anyone else use my Doziers because they are so sharp and the potential for deep cuts is so great when you are not used to a knife as sharp. Bob doesn't list kitchen knves per se on his website http://www.dozierknives.com but talk to Linda his wife and explain what you want and he will let you know of doable. He made me a 9" long carving knife that is flat ground and truly a great roast/turkey knife.-Dick

Edited December 29, 2003 by budrichard (log)

[MobyP]

I've been using a hand-made Artisan 10 inch blade from JKC here in London, and although breathtakingly sharp, I've found it horribly brittle. The blade has chipped several times, and the tip just broke off (from a very minor accident). I'm beginning to think I should just stay with my 10" wusthof. It may be 5 percent less sharp, but it's a work horse that I never need worry about.

[slkinsey]

All of the makers referenced here produce excellent blades. One that i would like to point out in particular is Bob Dozier. His blades are the sharpest non forged knives I have ever used.

Are you sure they're not forged? Or are you trying to say that they're not specially forged like Japanese knives? AFAIK, 99.999% of knife steel is forged. Isn't cast steel the only alternative to forged?

[Schielke]

What about stamped blades?

[Chad]

All of the makers referenced here produce excellent blades. One that i would like to point out in particular is Bob Dozier. His blades are the sharpest non forged knives I have ever used.

Are you sure they're not forged? Or are you trying to say that they're not specially forged like Japanese knives? AFAIK, 99.999% of knife steel is forged. Isn't cast steel the only alternative to forged?

Well, there are bangers and there are grinders. Forged, in this instance, means that the knife maker has taken a chunk of steel, heated it in a forge and hammered the knife into shape -- a process that takes several heatings, beatings & quenchings. Only knife makers who forge their blades are eligible for membership in the American Bladesmith Society -- the organization that certifies master knife makers.

Many other knife makers buy steel in billets or sheets and grind it to shape -- called the stock removal method of knife making. Almost invariably, any stainless knife (other than your cast dendritic) is made using the stock removal method. Stainless is too hard to forge.

Henckels, Wusthofs, et al, are drop forged -- a several ton press drops down on steel blanks and pounds them into shape in one fell swoop. From a custom knife maker's point of view, that ain't forging.

Chad

[Varmint]

And what is the meaning of "drop forged"?

[slkinsey]

And what is the meaning of "drop forged"?

See above: "a several ton press drops down on steel blanks and pounds them into shape in one fell swoop"

[slkinsey]

All of the makers referenced here produce excellent blades. One that i would like to point out in particular is Bob Dozier. His blades are the sharpest non forged knives I have ever used.

Are you sure they're not forged? Or are you trying to say that they're not specially forged like Japanese knives? AFAIK, 99.999% of knife steel is forged. Isn't cast steel the only alternative to forged?

Well, there are bangers and there are grinders. Forged, in this instance, means that the knife maker has taken a chunk of steel, heated it in a forge and hammered the knife into shape -- a process that takes several heatings, beatings & quenchings.

Okay, I see the point here. Not all forging is equal. But wouldn't you say it is true that, once you beat on the steel and break up the carbide crystals, the steel is forged? Isn't this true even of steel blanks used for the stock removal method? I'm not asking rhetorically -- I'm curious.

[Chad]

Well, we're getting outside my area of expertise. I don't know a whole lot about the steel manufacturing process. However, it is my understanding that a lot of steel (most?) is hot-rolled to thickness rather than being pounded flat with an air hammer or drop forge. Probably does about the same thing, but I'm not sure it's "forged."

Here's an excerpt from the Crucible Particle Metallurgy site.

There are significant differences between CPM and conventional steel making. Conventional steel making usually involves melting the steel in a large electric arc furnace, followed by a secondary refining process such as Argon Oxygen Decarburization(AOD). After refining, the molten metal is poured from a ladle into ingot molds, where the metal freezes slowly.

A characteristic feature of slow freezing in an ingot mold is that alloying elements segregate non-uniformly and carbides which precipitate early from the melt tend to grow larger until solidification is complete. Subsequent forging or rolling of the ingot is designed to break up and refine this as-cast structure, but the effects of the initial slow freezing rate are never fully eliminated. The higher the alloy content, the more seriously these structural features will affect the physical and mechanical properties of the steel. This non-uniformity limits how alloy content can be added to tool steels, and thus limits their potential wear resistance.

CPM uses a different process. They spray the molten metal through an atomizer to create a super fine powder which is then vacuum melted & pressed to create an incredibly intricate and fine carbide matrix. Good stuff. The bars are then rolled or forged like conventional steels.

So I guess you're right. Even bar stock steel is "forged" at some point. Just don't let the American Bladesmith Society hear you say it .

Chad

[AzRaeL]

What about stamped blades?

ewwww...stamped blades are verboten here.

ok seriously a few stamped blades are good because they're cheap and allow you more money to spend on your serious blades. But they're not pretty and definitely not lustworthy.

IMHO, knives that can be stamped:

fillet knife ( you dont really benefit from forged heft and all that jazz and the thinness of the blade is a must)

bread knife (ditto)

cake knife(that long broad thing you use to spread icing)

[budrichard]

My degrees are in Nuclear Engineering with a Minor in Metallurgy among other things. I have done graduate studies in Metallury and conducted research with electron microscopes on the effects of hydrogen ion bombardment on SS as the first wall material for controlled plasma fusion device. So even though my studies and research are a few years old, I do possess an adequate knowledge of steels.

In the custom knife world as Chad has correctly stated there are generally two methods of knifemaking, stock removal and forging. Many years ago a maker woud buy stock in flat billets that came from a mill and was produced by rolling out the ingot from the smelt. The rolling could have been done hot or cold, hence the terms hot or cold rolled. Hot rolled was softer because the dislocations produced by the rolling were somewhat annealed by the temp. Cold rolled needed to be annealed for working. The maker would then take the blank, cut with saw to rough size and then grind away. With the advent of newer cutting technicques this rough forming can be done by laser or other techniques. In some cases the maker

can get a material that is close to the final blade and does not require as much work. This has been along standing debate in the knife making community about what is custom and what is production. Corbet Sigman does stock removal entirely by hand, some do little stock removal.

Bill Moran is considerd the modern father of forging for custom knife making. Forging is where you start with material, billet, large steel bearings or what have you and heat it in a forge and pound it to shape. You can use a hammer or in many cases now a power forge. There is a constant debate about which method, forging or stock removal, produces the best blade. Personally I think they just reach the same destination by different routes. I have both forged and non forged by many makers. I just appreciate the artistry that goes in to forged blades more.

I have knives with CPM steel, stellite knives, just about anything you can name. Are any better? Not really. the significant differences are that carbon steel is easier to sharpen, high carbon not quite as easy but doesn't stain as easy. As you go up the ladder in esoteric steels the sharpening process becomes more and more difficult.

The hype for stellite and some of the other materials is that they are very tough and don't rust. BTW stellites claim to fame is as a surface material coating to reduce wear. A welder will take steliite rod to a 'dozer' blade and build up to reduce the wear.

Don't get caught up in the hype of carbides and how individuals interpret the effects of these particles on the steel performance. The real truth lies in performance and surface and electron microscopy and I do not know any makers that use these techniques to explain 'how' ther steel works. They just know what works for them by trial and error.

The buzz word Damascus signifies a sort of holy grail of steel. Pretty to look at, more expensive to produce, in reality the blades are about the same sharpness as other high quality materials. John Smith of Centralia Illinois has produced forged blades for me and is currently working on a Damascus blade for me. John will tell you that there is honestly not any significant difference he can ascertain. BTW Many maker do not produce thier own Damascus, but purchase it commercially and then perform thier stock removal techniques with it.

In short knife making and steels are subject to a constant discussion of what is best(sharp) and why is it best. Most of the discussions are by individuals not founded in a theoretical knowledge of Metalurgy but a working knowledge. They struggle to figure out why what they do produced the results that they obtain. In reality metalurgy is still not an exact science and subject to trial and error. That trial and error has produced the knowledge base that we have today. There is a company that claims to be able to mathematically predict the properties of alloys and got some press a few years ago in 'Wired' but my attempts to contact them were in vain, and the hype has petered out.

BTW stamped blades are 'verboten' in my home!

Hope this material helps.

[slkinsey]

Don't get caught up in the hype of carbides and how individuals interpret the effects of these particles on the steel performance. The real truth lies in performance and surface and electron microscopy and I do not know any makers that use these techniques to explain 'how' ther steel works.

Well, now you know one: David Boye.

The buzz word Damascus signifies a sort of holy grail of steel. Pretty to look at, more expensive to produce, in reality the blades are about the same sharpness as other high quality materials.

I'm not clear whether you're making just a general comment here about modern Damascus steel, or whether you're interpreting the earlier discussion regarding dendritic steel as relating to modern Damascus steel. As I understand it, they are two entirely different things. In re to dendritic steel, the one thing that I have observed through my own side-by-side testing is that it has markedly better edge-retention properties than any other steel I have used. Whether or not one steel inherrently provides a sharper edge... I'm not sure it's possible to say that. There are many different kinds of sharpness, and what counts as sharpness on one kind of edge doesn't on another. I've never been able to pop hair with a dendritic steel edge, which would make it "less sharp" than some fine grained forged steel edges I have in that respect... on the other hand, I can drag something across a dendritic steel edge and cut much more deeply than I can doing the same procedure with the fine grained forged edge.

Hope this material helps.

Yes! Thanks.

[Schielke]

Just to be clear, I was asking about stamped blades in reference to the comment about non-forged blades.

Ben

[budrichard]

I have observed over the years that knifemakers continue to find the 'Holy Grail' of steel. I am not sure where 'Dendritic Steel' lies in that quest.

Damascus is indeed different than 'dendritic steel'. Damascus can be done many different ways starting with different constituents, what they all have in common is the forging and welding, folding and reforging of the steel. Some makers have even claimed to have discovered the lost Damascus technique with Wootz steel. My point is that the real test is in how the blade performs. Corbet Sigman makes a line of 'Working' and a line of 'Utility' Hunters in addition to the collector blades. Many years ago i ordered a few Utility Hunters in Carbon steel for friends. One went to my Godson whose brother promptly left it outside for few days. It had to go back to Corbet to remove some rust. One, I let a guide use to gut and skin a bear i had shot. I offered him a tip or the knife. He took the knife and continues to swear by it to this day. I have blades by Corbet in S30V and other steels. The principle virtue of these steels is that they do not rust easily and retain an edge for a good amount of time. But when you need to sharpen, watch out, it is labor intensive.

I will have to puruse Boyle's website to figure out if I believe what he is saying.

I did look at his website and information. The picture of the carbides is done by surface metalography which means that a small sample is highly polished and then a specially designed microscope is used to look at the surface. It is obvious that his material is like stellite in that they are both rust free. It seems to cut well by the testimony given. Is it the 'Holy Grail' of knife materials? There are many makers that would tell you otherwise. My point is that it really doesn't matter what the material is or the hype associated with it, as long as it works for you.

For kitchen use, my customs just don't perform that much better to justify my switching and the different blades that i use are just not available from a custom maker. That is why i have standardized on Wusthof. They cut great, are fairly easy to sharpen and come in the largest variety of any manufacturer. But every once in a while a custom knife slips in there, I just can't help myself! -Dick

Edited December 30, 2003 by budrichard (log)