10 ms·

CPM MagnaCut

375 points by topsycatt 5y ago

bob_loblaw 5y ago
Very cool to see this pop up on Hacker News. I'm into pocket knives, and Larrin's new steel is generating a lot of hype among knife users and makers.
MrMember 5y ago
Really interesting read. It's cool that a company like Crucible was willing to consider a proposal for something as expensive, time consuming, and potentially fruitless as a new steel from essentially someone off the street.
- bob_loblaw 5y ago
  Larrin's father is a famous custom knife maker who worked with making his own Damascus-style steel. Larrin, though his father, is well-known among the knife community.
  - blacklion 5y ago
    It is unfair to Larrin to attribute his success and well-knowness to the father.
    - bob_loblaw 5y ago
      I wasn't trying to do that so I should clarify. MagnaCut is, so far, a success because of his unique approach. I asked on another forum if MagnaCut is using some new process that makes the balance of properties so much better than other steels on the market. Most cutlery steel dates back decades. I thought maybe what MagnaCut is doing relies on technology that wasn't available back then. Larrin said no. He deserves credit for his fresh approach to making a cutlery steel, and I should not have implied otherwise. My poorly worded response was more to Crucible taking a chance on somebody off the street. Larrin is not some unknown quantity. He has connections in the knife industry, including Crucible. He's also a metallurgist with accomplishments in his own right. Crucible still took a risk, but it wasn't a huge one.
- bts327 5y ago
  Not really sure I’d call Larrin “someone off the street.” They guy literally wrote the book on modern knife metallurgy and has a PhD in the science. https://www.amazon.com/Knife-Engineering-Steel-Treating-Geometry/dp/B08D4P9D95 https://www.amazon.com/Knife-Engineering-Steel-Treating-Geom... He also has a well known website and is considered one of the worlds leading experts on knife steels and knife craft.
- aidenn0 5y ago
  He has a PhD Metallurgical Engineering and works in the steel industry (though on automotive steels, not on knife steels). Not quite the same as someone off the street. From TFA the company was mainly worried that his knife-steel knowledge was purely academic (since he's never worked professionally on high carbon knife steels).
rkagerer 5y ago
This is a huge article. Can anyone give a 1-paragraph synopsis of its main thrust?
- bob_loblaw 5y ago
  MagnaCut is the first knife steel that does the best job of balancing edge retention, toughness, and corrosion resistance. It is basically a stainless 4V (if that means anything to you). Larrin focused on reducing the amount or chromium needed. Lots of steels will dump chromium into the steel to help corrosion resistance. This only helps if chromium remains in solution and not forming carbides with the iron. Chromium carbides don't offer much in the way of wear resistance (unless you have a ton of them like in ZDP-189) and they are large carbides (relatively speaking) even after the particle metallurgy process. Basically, you give up toughness when helping corrosion resistance (ignoring steels with nitrogen). Larrin uses a lower amount of chromium than you would expect, but it remains in solution. So you get the stain resistance you want without the chromium carbides. Other benefits of the steel include grindability, which means makers can spend less time and abrasives on shaping the knife. You can obtain higher hardness than a standard stainless steel, which helps with forming an apex and removing the burr (sharpness for lack of a better word). Spyderco, a major player in the knife world, has a line of knives called their Salt series. These knives are supposed to be as rust-free as one can make. MagnaCut will first enter their catalog as a Salt knife. This was a big shock given how well LC200N (nitrogen-based steel used by NASA for ball bearings) can resist rust and remain tough (wear resistance isn't anything special though). Bottom line, Larrin built a well-balanced steel exclusively for knives. Many steels are adopted from other industries or were "knife-specific" but based on something like 440C, which was never intended for cutlery. So MagnaCut is upending the knife steel market by offering something you can't get elsewhere.
  - jfengel 5y ago
    Is it possible to sharpen such a thing when it does get dull, or does that require a professional? In between sharpenings, does a steel work? (Sorry, I don't know much about steel or knife making. I just appreciate a really good kitchen knife.)
gxt 5y ago
Since I presume steel is a more or less uniform substance compared to biological processes, why is metallurgical research still more or less experiment first? Shouldn't it possible nowadays to bruteforce a search for an alloy of any given properties using computer simulations of the atomic or molecular structures?
- unbanned 5y ago
  No. This is knives, not science.
- kristjansson 5y ago
  Per TFA, it is to an extent? The author briefly discusses a computational search of the design space, and uses that data to encourage the partner company to make a batch of the steel. That said, simulating material properties from atomic scale principles seems nontrivial compared to predicting them given observed parameters and properties of other alloys. I’d be interested in more informed comments on that possibility!
- Tuna-Fish 5y ago
  The search space is much, much more vast than you'd imagine, and there are so many ways that things get non-linear that we have absolutely no idea how (way) more than 99.9999% of the possible alloys that we could make would actually perform in reality. The way most of the alloys we are using were found was that we started with something that we already knew, and then tweaked from there to optimize some property.
- kragen 5y ago
  It's a good question; unusually, that doesn't mean I don't have a good answer. Steel is so far from being a more or less uniform substance that it's not even funny. There are four major phases that play roles even in the commonest carbon steel (ferrite, cementite, austenite, and martensite), plus others that can form at times like graphite, which plays an important role in cast irons. Ferrite and cementite can form nanolaminated microstructures called pearlite and bainite which have a major influence on the properties of the steel, and there are other microstructures that form depending on cooling speed, heat treatment, and cold working. So even the simplest steel is a nanostructured composite of metal and ceramic whose properties are hard to model computationally, though great strides have been made in recent decades. Then, once you add other alloying elements besides those two (intentionally or not), steel stops being so simple. You can find phase diagrams for most of the binary systems (vanadium-carbon, for example, or vanadium-iron) but most of the ternary systems probably include compounds that haven't been identified yet. In theory you could find them computationally, I think. Even when you have a phase diagram, though, that doesn't tell you how fast the phase transitions happen, which depends on things like the crystal structures of intermediate unstable phases. I don't know anything about this stuff, I just read about it. Recommended! Start with https://www.tf.uni-kiel.de/matwis/amat/generalinfo_en/guided_tour.html https://www.tf.uni-kiel.de/matwis/amat/generalinfo_en/guided...
Straw 5y ago
How does this compare to Japanese steels such as HAP40 and Aogami White/Blue/Super?
- bob_loblaw 5y ago
  If you look at White/Blue/Super funny they will rust. HAP40 is a high-speed tool steel. CPM M4 is a good comparison to it. MagnaCut will offer corrosion resistance that you don't tend to see in Japanese steels. MagnaCut will have better edge retention than White/Blue/Super. Those steels are low-alloy and rely on high hardness for wear resistance. MagnaCut has vanadium and niobium plus it can get pretty hard as well. MagnaCut is so far ahead of White/Blue/Super in this regard. Japanese steels are known for being great to sharpen (even HAP40). From what I have read, MagnaCut sharpens well. If we say that MagnaCut = stainless 4V and HAP40 = CPM M4, then HAP40 should have some more edge retention but less toughness when compared to MagnaCut. The differences aren't all that great. Corrosion resistance is the real difference maker.
  - namibj 5y ago
    Do you know how tungsten carbide with nickel binder stacks up in comparison? The usual cobalt binder of course isn't that good in terms of corrosion resistance, but for e.g. vegetable knife purposes, sharpness is very much required, toughness only so much as a brittle blade shatters if you look at it funny, and edge retention determines whether you have to (learn to) sharpen it at location, or can transport it to a service center.
    - bob_loblaw 5y ago
      It is hard to make comparisons like this. I know that is a crappy answer. But geometry by far the most important characteristic. How thick is the overall blade stock? How thick is the knife behind the edge? Those two things will matter more than steel composition. Then you have heat treat. A great steel with a crappy heat treat is going to make for a lackluster knife. But, regarding tungsten. There is a steel called Maxamet, and it is used in several knives by Spyderco. It should be noted that I am a Spyderco fanboy, so take my recommendation of this company with a grain of salt. I like them more than any other production knife company, perhaps to a fault. Anyways, Maxamet is run really hard, like 67 HRC. Most production companies will run their knives in the upper 50's so the knives roll instead of chip. Quality production companies (Spyderco, Benchmade, Hinderer, Chris Reeve, etc.) will run most of their steels to around 59-60 HRC. Maxamet can cut for a long, long time. This steel has 2.15% iron (which helps with attaining a higher hardness), 10% cobalt, 13% tungsten, and 6% vanadium. I can't think of another steel used in cutlery with as much tungsten as Maxamet. The cutting numbers from this steel are near the top of the charts. So Maxamet will blow MagnaCut out of the water when it comes to edge retention, but it was designed as a high speed tool steel. MagnaCut was designed to be a "jack of all trades, master of none". Steels like Maxamet require skill and some special tools as a sharpener. It's all about choosing the right steel for the job. Often tradeoffs are involved. Steel chart - https://www.spyderco.com/edge-u-cation/steel-chart/ https://www.spyderco.com/edge-u-cation/steel-chart/ I will say that hard, thin knives have a reputation for chipping. Triple B Handmade Blades is a custom maker that focuses on maximizing cutting performance. So he uses high-carbide, high hardness, thin (like crazy thin) edges. You would think that his knives would shatter, but they do surprisingly well in his testing. Here's a short video of Rex 121 (has the highest percentage of carbide volume) heat treated to over 70 HRC. He is performing twisting cuts with a hard wood. At the end, the knife still cleanly cuts paper. You don't see/hear any chipping. https://www.youtube.com/watch?v=xAPMXGvrJ1I https://www.youtube.com/watch?v=xAPMXGvrJ1I
nimbius 5y ago
I'm sure this will get down voted as its a Luddites call to arms, but all my cutlery is simple high carbon steel. Its cheap, holds an excellent edge, and in the kitchen it develops a wonderful rustic patina. For a pocket knife, a few drops of oil once or twice a year will keep it in good order, or you can chemically blue it if that suits your style as well.
- jimmar 5y ago
  I have family members who refuse to clean knifes properly. I need stainless steel. Personally, I'd prefer to have high carbon, but I know it'd be a rusted mess in a month.
  - yumraj 5y ago
    I've had great success with Victorinox stainless steel knives. They are pretty sharp, for us anyway, and seem to keep that way. And, they seem to be pretty reasonably priced.
- yumraj 5y ago
  any recommended brands? or are these custom made?
  - bob_loblaw 5y ago
    Spyderco, but I am a fanboy. Their forums are really insightful. If you do down the rabbit hole of knives and steel, Spyderco does a better job of catering to this market. They experiment with all kinds of steel that will never make it to another production company. It should be noted, Spyderco knives tend to be on the "ugly" side. It took me a while to get them as a company. Benchmade, Hinderer, Chris Reeve, Spartan, Demko, etc. The list goes on and on. This is a great time to be a knife knut.
    - yumraj 5y ago
      > This is a great time to be a knife knut. Curious as to why is that?
BatFastard 5y ago
Great looking knife, but 10 minutes of looking doesn't reveal where to buy one!
- bob_loblaw 5y ago
  The first batch was given to smaller makers, often custom makers. Right now, Tactile Turn is offering a couple knives in MagnaCut (change the option in the drop down). I've seen people say they have used up their MagnaCut already. The steel will probably trickle into the market. Spyderco announced that the Native 5 Salt will come in MagnaCut. No date has been given for that. https://tactileknife.co/products/rockwall-thumbstud https://tactileknife.co/products/rockwall-thumbstud
  - rdtwo 5y ago
    That’s a nice knife, the spiderco looks pretty shitty in comparison
    - spekcular 5y ago
      Spyderco takes pride in their knives looking ugly. They're totally form over function. Comparing the handles, I'm pretty sure the Spyderco would feel many times better in my hand. Also, they have amazing fit and finish, and come razor sharp from the factory. An expensive brand, to be sure, but I have only good things to say.
      - rdtwo 5y ago
        How do you sharpen those serrated blades? I get function on serrated but I don’t really want a 150$ + knife to be disposable because it can’t be sharpened
        spekcular 5y ago
        It's tricky. Typically you get thin rods and do each serration individually. Spyderco sells their "Sharpmaker" for this. It's a bit overpriced; you can find decent substitutes elsewhere. Generally non-serrated edges are preferable unless you have a special requirement, like cutting rope. That yellow Native is part of their "salt" series for people who work on/around boats and water, and hence need to cut rope for sails, etc. Here corrosion resistance is obviously of paramount importance, which is why they use different steels for "salt" knives. There are also plainedge Natives around, for example: https://www.smkw.com/spyderco-native-5-lghtwt-blue-frn https://www.smkw.com/spyderco-native-5-lghtwt-blue-frn.
causality0 5y ago
I wonder how MagnaCut compares to INFI. I've seen knives made of the latter do things I would've considered flatly impossible.
- bob_loblaw 5y ago
  Elastic ceramic is a pretty wild material as well. You can do stuff with it that seems impossible with steel.
ChrisMarshallNY 5y ago
Now, that is a labor of love! I find good chef's knives to be worth their price, but the truly awesome ones are a bit out of my price/performance range. If I made my living as a chef, I might think differently.
- denton-scratch 5y ago
  I like to cook; I bought a carbon-steel chef's knife 25 years ago, made by Richardson Steel of Sheffield. Regrettably they don't make steel in Sheffield any more, and that brand was sold to some Chinese company. The knife rusts if you let it; I call the result a 'patina'. It takes a wicked edge. It's still my go-to kitchen knife. Just now I'm a beardie-wierdie; but I usually shave through the summer, using straight razors. These are also carbon steel, although I think one of my razors at least must have some chromium in it - it seems to resist tarnishing. So: I wonder how this material compares to that Sheffield carbon steel for hardness and toughness. And I wonder how it compares with the Solingen steel my two daily razors are made of. As far as I'm concerned, a straight razor is the pinnacle of blade-making (I might take a different view if I was into swords). One of my razors belonged to my father, and is Sheffield carbon steel. It was made in the 1930s, and I can't get it nearly as sharp as the modern Solingen steel razors (I tried shaving with it once, but it wasn't 'smooth'). I didn't get what hardening, tempering and annealing processes he applied; that makes a huge difference to the kind of steel you end up with. I'm just a blade user, not a metallurgist or cutler. I'm just interested in high-performance blades. I wonder if this metal makes nice razors?
thurn 5y ago
So is this getting us any closer to making a knife I can regularly put in the dishwasher, or are we still limited by the technology of our time?
- driverdan 5y ago
  Why? It literally takes less than 15 seconds to clean and dry a stainless knife.
- teruakohatu 5y ago
  I put my Victorinox in the dishwasher with no ill effect. The biggest danger is when a visitor decides to chop a tomoto on a ceramic plate. It's no Japanese chef knife, but a bargin for what it is.
  - jerrysievert 5y ago
    I have a nice set of Japanese chefs knives, and still use my victorinox on a regular basis. it's hard to argue with being able to drop it in the dishwasher. my 8" victorinox will be 8 years old in march, and is still going very strong, quite the bargain.
  - bob_loblaw 5y ago
    I read that Victorinox regular tests their knives with a dishwasher. While knife people will cringe at this, to many a knife is but a tool. When the tool is dirty, throw it in the dishwasher with the other dirty kitchen tools. Makes sense, but I'd never do it. The best part about the Victorinox line of knives is there handles. You can't ruin them with the dishwasher. Wood and other natural materials don't fare well in the dishwasher. Their steel (note quite sure what it is) is very corrosion resistant as well. It holds an edge long enough, and it is easy to sharpen. If you are a "knife is a tool" kind of a person, go with Victorinox.
insaneirish 5y ago
Larrin was on one of my favorite podcasts, Cooking Issues, to talk about various knife related things. Very good discussion. Episode link: https://www.patreon.com/posts/knives-out-with-52817284 https://www.patreon.com/posts/knives-out-with-52817284 You do not need to be a Patron subscriber to listen to the episode. Also, if you're interested in the technical side of cooking and drink making, Cooking Issues is the podcast to listen to. There's a huge back catalog of shows on their former network, HRN, as well as a bunch of shows via their new arrangement.
- dunham 5y ago
  Thanks. I occasionally read their blog back in the day, but didn't know they were still producing stuff.
  - insaneirish 5y ago
    And making stuff!: https://www.indiegogo.com/projects/searzall-pro#/ https://www.indiegogo.com/projects/searzall-pro#/
deleted 5y ago
[deleted]
The_rationalist 5y ago
Where can we buy magnacut knifes? (for cooking if possible)
- vxNsr 5y ago
  This knife enthusiast[0] implies that this steel isn't necessary in the kitchen Though I had the same question, I'm guessing it'll be a few years and it'll be very expensive. [0]https://news.ycombinator.com/item?id=29697285 https://news.ycombinator.com/item?id=29697285
- bob_loblaw 5y ago
  Spyderco already announced MagnaCut in their 2022 catalog. However, they are backed up at the moment. I am not holding my breath for a release in the near future. Custom makers tend to be on the cutting edge (no pun intended) when it comes to using "odd" steels. I expect more and more people to use it. That said, will Crucible make enough for demand? There's not a ton of money in knife steel production. Right now, Crucible's latest cutlery steel is S45Vn. S35Vn and S30V are still widely used as well. 20CV has taken off a bit too. I don't think Crucible will start making large batches just yet. But, I could be wrong.
ks92 5y ago
In metallurgy, several computational models are available based on specific applications. University of Cambridge is involved in neural network modeling. Just recently I published a paper that analyzed a welding electrode database to provide specific insights. One could see it here, https://s3.amazonaws.com/WJ-www.aws.org/supplement/2021.100.036.pdf https://s3.amazonaws.com/WJ-www.aws.org/supplement/2021.100....

375 points by topsycatt 5y ago

Very cool to see this pop up on Hacker News. I'm into pocket knives, and Larrin's new steel is generating a lot of hype among knife users and makers.

MrMember 5y ago

Really interesting read. It's cool that a company like Crucible was willing to consider a proposal for something as expensive, time consuming, and potentially fruitless as a new steel from essentially someone off the street.

bob_loblaw 5y ago
Larrin's father is a famous custom knife maker who worked with making his own Damascus-style steel. Larrin, though his father, is well-known among the knife community.
- blacklion 5y ago
  It is unfair to Larrin to attribute his success and well-knowness to the father.
  - bob_loblaw 5y ago
    I wasn't trying to do that so I should clarify. MagnaCut is, so far, a success because of his unique approach. I asked on another forum if MagnaCut is using some new process that makes the balance of properties so much better than other steels on the market. Most cutlery steel dates back decades. I thought maybe what MagnaCut is doing relies on technology that wasn't available back then. Larrin said no. He deserves credit for his fresh approach to making a cutlery steel, and I should not have implied otherwise. My poorly worded response was more to Crucible taking a chance on somebody off the street. Larrin is not some unknown quantity. He has connections in the knife industry, including Crucible. He's also a metallurgist with accomplishments in his own right. Crucible still took a risk, but it wasn't a huge one.
bts327 5y ago
Not really sure I’d call Larrin “someone off the street.” They guy literally wrote the book on modern knife metallurgy and has a PhD in the science. https://www.amazon.com/Knife-Engineering-Steel-Treating-Geometry/dp/B08D4P9D95 https://www.amazon.com/Knife-Engineering-Steel-Treating-Geom... He also has a well known website and is considered one of the worlds leading experts on knife steels and knife craft.
aidenn0 5y ago
He has a PhD Metallurgical Engineering and works in the steel industry (though on automotive steels, not on knife steels). Not quite the same as someone off the street. From TFA the company was mainly worried that his knife-steel knowledge was purely academic (since he's never worked professionally on high carbon knife steels).

rkagerer 5y ago

This is a huge article. Can anyone give a 1-paragraph synopsis of its main thrust?

bob_loblaw 5y ago
MagnaCut is the first knife steel that does the best job of balancing edge retention, toughness, and corrosion resistance. It is basically a stainless 4V (if that means anything to you). Larrin focused on reducing the amount or chromium needed. Lots of steels will dump chromium into the steel to help corrosion resistance. This only helps if chromium remains in solution and not forming carbides with the iron. Chromium carbides don't offer much in the way of wear resistance (unless you have a ton of them like in ZDP-189) and they are large carbides (relatively speaking) even after the particle metallurgy process. Basically, you give up toughness when helping corrosion resistance (ignoring steels with nitrogen). Larrin uses a lower amount of chromium than you would expect, but it remains in solution. So you get the stain resistance you want without the chromium carbides. Other benefits of the steel include grindability, which means makers can spend less time and abrasives on shaping the knife. You can obtain higher hardness than a standard stainless steel, which helps with forming an apex and removing the burr (sharpness for lack of a better word). Spyderco, a major player in the knife world, has a line of knives called their Salt series. These knives are supposed to be as rust-free as one can make. MagnaCut will first enter their catalog as a Salt knife. This was a big shock given how well LC200N (nitrogen-based steel used by NASA for ball bearings) can resist rust and remain tough (wear resistance isn't anything special though). Bottom line, Larrin built a well-balanced steel exclusively for knives. Many steels are adopted from other industries or were "knife-specific" but based on something like 440C, which was never intended for cutlery. So MagnaCut is upending the knife steel market by offering something you can't get elsewhere.
- jfengel 5y ago
  Is it possible to sharpen such a thing when it does get dull, or does that require a professional? In between sharpenings, does a steel work? (Sorry, I don't know much about steel or knife making. I just appreciate a really good kitchen knife.)

gxt 5y ago

Since I presume steel is a more or less uniform substance compared to biological processes, why is metallurgical research still more or less experiment first? Shouldn't it possible nowadays to bruteforce a search for an alloy of any given properties using computer simulations of the atomic or molecular structures?

unbanned 5y ago
No. This is knives, not science.
kristjansson 5y ago
Per TFA, it is to an extent? The author briefly discusses a computational search of the design space, and uses that data to encourage the partner company to make a batch of the steel. That said, simulating material properties from atomic scale principles seems nontrivial compared to predicting them given observed parameters and properties of other alloys. I’d be interested in more informed comments on that possibility!
Tuna-Fish 5y ago
The search space is much, much more vast than you'd imagine, and there are so many ways that things get non-linear that we have absolutely no idea how (way) more than 99.9999% of the possible alloys that we could make would actually perform in reality. The way most of the alloys we are using were found was that we started with something that we already knew, and then tweaked from there to optimize some property.
kragen 5y ago
It's a good question; unusually, that doesn't mean I don't have a good answer. Steel is so far from being a more or less uniform substance that it's not even funny. There are four major phases that play roles even in the commonest carbon steel (ferrite, cementite, austenite, and martensite), plus others that can form at times like graphite, which plays an important role in cast irons. Ferrite and cementite can form nanolaminated microstructures called pearlite and bainite which have a major influence on the properties of the steel, and there are other microstructures that form depending on cooling speed, heat treatment, and cold working. So even the simplest steel is a nanostructured composite of metal and ceramic whose properties are hard to model computationally, though great strides have been made in recent decades. Then, once you add other alloying elements besides those two (intentionally or not), steel stops being so simple. You can find phase diagrams for most of the binary systems (vanadium-carbon, for example, or vanadium-iron) but most of the ternary systems probably include compounds that haven't been identified yet. In theory you could find them computationally, I think. Even when you have a phase diagram, though, that doesn't tell you how fast the phase transitions happen, which depends on things like the crystal structures of intermediate unstable phases. I don't know anything about this stuff, I just read about it. Recommended! Start with https://www.tf.uni-kiel.de/matwis/amat/generalinfo_en/guided_tour.html https://www.tf.uni-kiel.de/matwis/amat/generalinfo_en/guided...

Straw 5y ago

How does this compare to Japanese steels such as HAP40 and Aogami White/Blue/Super?

bob_loblaw 5y ago
If you look at White/Blue/Super funny they will rust. HAP40 is a high-speed tool steel. CPM M4 is a good comparison to it. MagnaCut will offer corrosion resistance that you don't tend to see in Japanese steels. MagnaCut will have better edge retention than White/Blue/Super. Those steels are low-alloy and rely on high hardness for wear resistance. MagnaCut has vanadium and niobium plus it can get pretty hard as well. MagnaCut is so far ahead of White/Blue/Super in this regard. Japanese steels are known for being great to sharpen (even HAP40). From what I have read, MagnaCut sharpens well. If we say that MagnaCut = stainless 4V and HAP40 = CPM M4, then HAP40 should have some more edge retention but less toughness when compared to MagnaCut. The differences aren't all that great. Corrosion resistance is the real difference maker.
- namibj 5y ago
  Do you know how tungsten carbide with nickel binder stacks up in comparison? The usual cobalt binder of course isn't that good in terms of corrosion resistance, but for e.g. vegetable knife purposes, sharpness is very much required, toughness only so much as a brittle blade shatters if you look at it funny, and edge retention determines whether you have to (learn to) sharpen it at location, or can transport it to a service center.
  - bob_loblaw 5y ago
    It is hard to make comparisons like this. I know that is a crappy answer. But geometry by far the most important characteristic. How thick is the overall blade stock? How thick is the knife behind the edge? Those two things will matter more than steel composition. Then you have heat treat. A great steel with a crappy heat treat is going to make for a lackluster knife. But, regarding tungsten. There is a steel called Maxamet, and it is used in several knives by Spyderco. It should be noted that I am a Spyderco fanboy, so take my recommendation of this company with a grain of salt. I like them more than any other production knife company, perhaps to a fault. Anyways, Maxamet is run really hard, like 67 HRC. Most production companies will run their knives in the upper 50's so the knives roll instead of chip. Quality production companies (Spyderco, Benchmade, Hinderer, Chris Reeve, etc.) will run most of their steels to around 59-60 HRC. Maxamet can cut for a long, long time. This steel has 2.15% iron (which helps with attaining a higher hardness), 10% cobalt, 13% tungsten, and 6% vanadium. I can't think of another steel used in cutlery with as much tungsten as Maxamet. The cutting numbers from this steel are near the top of the charts. So Maxamet will blow MagnaCut out of the water when it comes to edge retention, but it was designed as a high speed tool steel. MagnaCut was designed to be a "jack of all trades, master of none". Steels like Maxamet require skill and some special tools as a sharpener. It's all about choosing the right steel for the job. Often tradeoffs are involved. Steel chart - https://www.spyderco.com/edge-u-cation/steel-chart/ https://www.spyderco.com/edge-u-cation/steel-chart/ I will say that hard, thin knives have a reputation for chipping. Triple B Handmade Blades is a custom maker that focuses on maximizing cutting performance. So he uses high-carbide, high hardness, thin (like crazy thin) edges. You would think that his knives would shatter, but they do surprisingly well in his testing. Here's a short video of Rex 121 (has the highest percentage of carbide volume) heat treated to over 70 HRC. He is performing twisting cuts with a hard wood. At the end, the knife still cleanly cuts paper. You don't see/hear any chipping. https://www.youtube.com/watch?v=xAPMXGvrJ1I https://www.youtube.com/watch?v=xAPMXGvrJ1I

nimbius 5y ago

I'm sure this will get down voted as its a Luddites call to arms, but all my cutlery is simple high carbon steel. Its cheap, holds an excellent edge, and in the kitchen it develops a wonderful rustic patina. For a pocket knife, a few drops of oil once or twice a year will keep it in good order, or you can chemically blue it if that suits your style as well.

jimmar 5y ago
I have family members who refuse to clean knifes properly. I need stainless steel. Personally, I'd prefer to have high carbon, but I know it'd be a rusted mess in a month.
- yumraj 5y ago
  I've had great success with Victorinox stainless steel knives. They are pretty sharp, for us anyway, and seem to keep that way. And, they seem to be pretty reasonably priced.
yumraj 5y ago
any recommended brands? or are these custom made?
- bob_loblaw 5y ago
  Spyderco, but I am a fanboy. Their forums are really insightful. If you do down the rabbit hole of knives and steel, Spyderco does a better job of catering to this market. They experiment with all kinds of steel that will never make it to another production company. It should be noted, Spyderco knives tend to be on the "ugly" side. It took me a while to get them as a company. Benchmade, Hinderer, Chris Reeve, Spartan, Demko, etc. The list goes on and on. This is a great time to be a knife knut.
  - yumraj 5y ago
    > This is a great time to be a knife knut. Curious as to why is that?

BatFastard 5y ago

Great looking knife, but 10 minutes of looking doesn't reveal where to buy one!

bob_loblaw 5y ago
The first batch was given to smaller makers, often custom makers. Right now, Tactile Turn is offering a couple knives in MagnaCut (change the option in the drop down). I've seen people say they have used up their MagnaCut already. The steel will probably trickle into the market. Spyderco announced that the Native 5 Salt will come in MagnaCut. No date has been given for that. https://tactileknife.co/products/rockwall-thumbstud https://tactileknife.co/products/rockwall-thumbstud
- rdtwo 5y ago
  That’s a nice knife, the spiderco looks pretty shitty in comparison
  - spekcular 5y ago
    Spyderco takes pride in their knives looking ugly. They're totally form over function. Comparing the handles, I'm pretty sure the Spyderco would feel many times better in my hand. Also, they have amazing fit and finish, and come razor sharp from the factory. An expensive brand, to be sure, but I have only good things to say.
    - rdtwo 5y ago
      How do you sharpen those serrated blades? I get function on serrated but I don’t really want a 150$ + knife to be disposable because it can’t be sharpened
      - spekcular 5y ago
        It's tricky. Typically you get thin rods and do each serration individually. Spyderco sells their "Sharpmaker" for this. It's a bit overpriced; you can find decent substitutes elsewhere. Generally non-serrated edges are preferable unless you have a special requirement, like cutting rope. That yellow Native is part of their "salt" series for people who work on/around boats and water, and hence need to cut rope for sails, etc. Here corrosion resistance is obviously of paramount importance, which is why they use different steels for "salt" knives. There are also plainedge Natives around, for example: https://www.smkw.com/spyderco-native-5-lghtwt-blue-frn https://www.smkw.com/spyderco-native-5-lghtwt-blue-frn.

causality0 5y ago

I wonder how MagnaCut compares to INFI. I've seen knives made of the latter do things I would've considered flatly impossible.

bob_loblaw 5y ago
Elastic ceramic is a pretty wild material as well. You can do stuff with it that seems impossible with steel.

ChrisMarshallNY 5y ago

Now, that is a labor of love! I find good chef's knives to be worth their price, but the truly awesome ones are a bit out of my price/performance range. If I made my living as a chef, I might think differently.

denton-scratch 5y ago
I like to cook; I bought a carbon-steel chef's knife 25 years ago, made by Richardson Steel of Sheffield. Regrettably they don't make steel in Sheffield any more, and that brand was sold to some Chinese company. The knife rusts if you let it; I call the result a 'patina'. It takes a wicked edge. It's still my go-to kitchen knife. Just now I'm a beardie-wierdie; but I usually shave through the summer, using straight razors. These are also carbon steel, although I think one of my razors at least must have some chromium in it - it seems to resist tarnishing. So: I wonder how this material compares to that Sheffield carbon steel for hardness and toughness. And I wonder how it compares with the Solingen steel my two daily razors are made of. As far as I'm concerned, a straight razor is the pinnacle of blade-making (I might take a different view if I was into swords). One of my razors belonged to my father, and is Sheffield carbon steel. It was made in the 1930s, and I can't get it nearly as sharp as the modern Solingen steel razors (I tried shaving with it once, but it wasn't 'smooth'). I didn't get what hardening, tempering and annealing processes he applied; that makes a huge difference to the kind of steel you end up with. I'm just a blade user, not a metallurgist or cutler. I'm just interested in high-performance blades. I wonder if this metal makes nice razors?

thurn 5y ago

So is this getting us any closer to making a knife I can regularly put in the dishwasher, or are we still limited by the technology of our time?

driverdan 5y ago
Why? It literally takes less than 15 seconds to clean and dry a stainless knife.
teruakohatu 5y ago
I put my Victorinox in the dishwasher with no ill effect. The biggest danger is when a visitor decides to chop a tomoto on a ceramic plate. It's no Japanese chef knife, but a bargin for what it is.
- jerrysievert 5y ago
  I have a nice set of Japanese chefs knives, and still use my victorinox on a regular basis. it's hard to argue with being able to drop it in the dishwasher. my 8" victorinox will be 8 years old in march, and is still going very strong, quite the bargain.
- bob_loblaw 5y ago
  I read that Victorinox regular tests their knives with a dishwasher. While knife people will cringe at this, to many a knife is but a tool. When the tool is dirty, throw it in the dishwasher with the other dirty kitchen tools. Makes sense, but I'd never do it. The best part about the Victorinox line of knives is there handles. You can't ruin them with the dishwasher. Wood and other natural materials don't fare well in the dishwasher. Their steel (note quite sure what it is) is very corrosion resistant as well. It holds an edge long enough, and it is easy to sharpen. If you are a "knife is a tool" kind of a person, go with Victorinox.

insaneirish 5y ago

Larrin was on one of my favorite podcasts, Cooking Issues, to talk about various knife related things. Very good discussion. Episode link: https://www.patreon.com/posts/knives-out-with-52817284 https://www.patreon.com/posts/knives-out-with-52817284 You do not need to be a Patron subscriber to listen to the episode. Also, if you're interested in the technical side of cooking and drink making, Cooking Issues is the podcast to listen to. There's a huge back catalog of shows on their former network, HRN, as well as a bunch of shows via their new arrangement.

dunham 5y ago
Thanks. I occasionally read their blog back in the day, but didn't know they were still producing stuff.
- insaneirish 5y ago
  And making stuff!: https://www.indiegogo.com/projects/searzall-pro#/ https://www.indiegogo.com/projects/searzall-pro#/

deleted 5y ago

[deleted]

The_rationalist 5y ago

Where can we buy magnacut knifes? (for cooking if possible)

vxNsr 5y ago
This knife enthusiast[0] implies that this steel isn't necessary in the kitchen Though I had the same question, I'm guessing it'll be a few years and it'll be very expensive. [0]https://news.ycombinator.com/item?id=29697285 https://news.ycombinator.com/item?id=29697285
bob_loblaw 5y ago
Spyderco already announced MagnaCut in their 2022 catalog. However, they are backed up at the moment. I am not holding my breath for a release in the near future. Custom makers tend to be on the cutting edge (no pun intended) when it comes to using "odd" steels. I expect more and more people to use it. That said, will Crucible make enough for demand? There's not a ton of money in knife steel production. Right now, Crucible's latest cutlery steel is S45Vn. S35Vn and S30V are still widely used as well. 20CV has taken off a bit too. I don't think Crucible will start making large batches just yet. But, I could be wrong.

ks92 5y ago

In metallurgy, several computational models are available based on specific applications. University of Cambridge is involved in neural network modeling. Just recently I published a paper that analyzed a welding electrode database to provide specific insights. One could see it here, https://s3.amazonaws.com/WJ-www.aws.org/supplement/2021.100.036.pdf https://s3.amazonaws.com/WJ-www.aws.org/supplement/2021.100....