Corrosion Testing of 9 Stainless Knife Steels

Discussion in 'The Kitchen Knife' started by Larrin, Oct 14, 2019.

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  1. Oct 14, 2019 #1

    Larrin

    Larrin

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  2. Oct 14, 2019 #2

    Gjackson98

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    Good read!
     
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  3. Oct 14, 2019 #3

    Alder26

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    I would be interested to see how VG-10 would perform in such a test.
     
  4. Oct 14, 2019 #4

    Larrin

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    Perhaps my rating for VG-10 in the table near the bottom of the article would provide some information on how it might do.
     
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  5. Oct 14, 2019 #5

    Alder26

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    haha My bad! Seems as though it is a middle of the road competitor. Also interesting to read about heat treat effecting corrosion resistance. I have always felt some of my knives with the same steel are more/less reactive but never knew for sure whether I was founded in thinking that
     
  6. Oct 14, 2019 #6

    Sharpchef

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    Please come to topic.......

    You do so nice tests... but they are not worth it. sorry.

    Take a look on the kitchen knifes used, this is just like your catra test not at all worthy for kitchen work.

    Greets Sebastian.
     
  7. Oct 14, 2019 #7

    Larrin

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    Doesn't sound like you're that sorry to me.
     
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  8. Oct 14, 2019 #8

    Sharpchef

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    You got the opportunity to do very good things.. But you simply don`t do it. This is what i argue about. Take the Catra testing, the outcome was the complete opposite of the real world cutting experience...

    Make it simple (only a few here understand your writings...) and make it clear, point to it! You can do it, but test maybe edge retention on common steels for the kitchen, not with XYZ steels...

    Btw. i like your research very much! i understand maybe 50% and i am in this steel thing...

    Hope you get me,

    greets Sebastian.
     
  9. Oct 14, 2019 #9
    Those with no education and no research behind them are the most critical.

    Hoss
     
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  10. Oct 14, 2019 #10

    Barclid

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    Similar to how it seems those who use their tools the least care the most about things that don't matter.
     
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  11. Oct 14, 2019 #11

    Interapid101

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    This seems like proof that gut feelings are often more persuasive than real data (for some folks).

    What are you trying to achieve with these posts?
     
  12. Oct 14, 2019 #12

    Keith Sinclair

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    Stainless steel has it's place. Just watched how they built a huge containment structure to cover Chernobyl.

    Stainless bolts on exposed motorcycle engines are a must. Knives I like are sure to rust:)

    I like Larrin's posts
     
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  13. Oct 14, 2019 #13

    valgard

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    That was fun to read.
     
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  14. Oct 14, 2019 #14

    LostHighway

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    I make no pretensions of being a metallurgist but I appreciate the Larrin/Knife Steel Nerds posts. While this is way outside of any area where I can even pretend expertise I have worked as a research assistant and at least have a vague grasp of how science works. Research tries to control for a single variable at a time and unless you have unlimited time and funding accounting for every possible variable is almost never an option. I would guess that variations in water temperature, water chemistry (including the presence or absence of surfactant/detergent exposure), ambient humidity in storage, steel tempering, possible contaminants introduced in forging and finishing, and a number of other variables might potentially change the results. None of this in a any way negates the value of Larrin's work. Anecdotal experience may suggest the need for further research but it in no way negates the data nor is it a good basis for generalization to broader "truths."
     
  15. Oct 14, 2019 #15

    Scribbled

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    I have absolutely no background in metallurgy, and freely admit to taking notes when I started reading Larrin’s site, but I found it hugely enjoyable and very interesting. I hope that he doesn’t simplify his writing.
     
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  16. Oct 14, 2019 #16
    Thank you for the article Larrin. I just gave it a quick read, but those results do give the denomination’Stainless’ a true meaning - especially when compared to ‘Rostfrei’ :)
     
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  17. Oct 14, 2019 #17
    A lot of litter in here....

    Appreciate (but can't always follow) your work Devin and Larrin.
     
  18. Oct 14, 2019 #18
    Sharp(?), perhaps you could post your own hypothesis and defend it elsewhere in the forum. It's easy to throw rocks, gets a little tougher when they're being thrown at you.
     
  19. Oct 14, 2019 #19

    M1k3

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    Thanks Larrin! Great article.
     
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  20. Oct 14, 2019 #20

    Barmoley

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    Thanks mods for cleaning this up a bit. It got rediculous fast. It always bugles my mind when people claim that studying and testing steels and their various attributes has no relevance to kitchen knives or outdoor knives or folders or whatever. How can a study of the matterials your tool is made out of have no relevance to your tool. It seems to matter in every other industry, but when it comes to knives, all of a sudden, "Oh this test or that is not relevant to me cutting tomatoes, etc" Of course it matters, wear resistance, toughness, corrosion resistance all matter. Some claim that specific tests don't mimic exactly what they do or cut, so what? They still give you a reference point, you can extrapolate and you can draw conclusions. Moreover, suggest something better, or better yet do your own testing and present it.

    Larrin doesn't tell you which steels to use for kitchen knives, he tests steels and explains his testing and conclusions. Draw your own conclusions about your own use or do your own testing and report back. So far I haven't seen anyone do this better and explain it better than Larrin, so I am not sure what some people are complaining about.

    Sometimes I feel like most people who complain about these tests, didn't even read the articles.
     
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  21. Oct 14, 2019 #21

    bahamaroot

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    I try to just skim some of these articles but I find them so fascinating that I have to read them from start to finish.
    Another great article Larrin, I thoroughly enjoyed it! I learn something new with every read.
     
    Last edited: Oct 15, 2019
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  22. Oct 14, 2019 #22

    captaincaed

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    There's great value to both quantitative and qualitative information. These investigations are the quantitative (measurement) side. Your experience in the kitchen is the qualitative (lived experience) side. Both really matter.

    E.g. Are condoms 99 percent effective at stopping unplanned pregnancy when used correctly? Damn right they are. So why is teenage pregnancy high? Because they're not fun to use, reduce pleasure the one place you want it, and they stink like monkeys in formaldehyde. So while the ITEM is super effective, the APPLICATION of the tool varies in context.

    Let's try another experiment. How many cool articles will be published when the tone of feedback is "eh....I think you're wrong *mic drop*"?
     
  23. Oct 15, 2019 #23

    rob

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    Great read,

    Thank you.
     
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  24. Oct 15, 2019 #24

    McMan

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    Thanks for this Larrin.
    You're a smart dude and, after today, it's clear a patient one too :cool:
     
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  25. Oct 15, 2019 #25

    GoodMagic

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    Larrin,

    I am really appreciative of your posts, they offer sound empiric data which informs and educates me. They are relevant and thought provoking. So thank you for the time and effort. Eric
     
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  26. Oct 15, 2019 #26

    K813zra

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    Thanks for posting. Many, many of your posts are above and beyond anything that I actually need to know but I enjoy reading them. It is fun comparing your findings to what I see in my home use as well. (Not much in the way of corrosion but other topics carry over quite a bit.)
     
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  27. Oct 15, 2019 #27

    HRC_64

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    There is tons of useful content and information in these articles larrin puts out,
    we should appreciate that and read them with an open mind.

    Its sort of a mark of education to be able to take "imperfect information" and make it useful yourself....
    so complaining that these articles aren't perfect or aren't perfectly suited to one person's view of the world, etc
    i think is a bit narrow minded.

    In "reality" a kitchen is very much a controlled environemnt, with a roof over the head,
    and access to plenty of fresh water and plenty of towels...this makes the defnition of "stainless"
    effectively different than if we were looking at hunting knife, scuba diver knives, pocket knives
    for the armed forces, etc...

    That is OK, and we can talk about all these things and how we might want diffferent tradeoffs
    for sharpening and machinability on a 10 inch vs a 3 inch blade also...

    But those kind of conversations are often shallow and meaningless without good data,
    good refrence points, etc to provide for real world evidence to discuss these issues.
     
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  28. Oct 15, 2019 #28

    Nemo

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    A couple of observations about some of the comments (some of which have now been removed) made in this thread:

    1) Larrin's articles follow a scientific approach, which is specifically designed to find things that don't agree with intuition. This is how new discoveries are made.

    As an off-topic example, general relativity and quantum physics are ridiculously counterintuitive but they have been proven by experiment time and time again. You rely on technologies every day that wouldn't work without our understanding of them.

    It is interesting that on the one hand, one of the commenters in this thread often asks us to suspend our intuition on sharpening jigs (FWIW, I suspect with good reason, although I am interested to see actual empirical (measured) data rather than simply assertions) yet is not willing to suspend his intuition on (for example) edge angles.


    2) I reject the assertion that Larrin's articles are not useful to most forum members because they use a scientific technique. Many members have commented that they have found Larrin's articles interesting and enlightening. If you don't, don't read them.


    3) If Larrin's results disagree with your intuition, either:
    A. Review your intuition,
    B. Provide some evidence that contradicts his results or
    C. Make a coherent argument that the methodology needs fine tuning.

    Dont just make unsubstantiated assertions that it can't be true because... intuition. And keep your comments and arguments polite and focussed on the facts. Play the ball, not the man. Too much playing the man in this thread. Easy to see as trolling, this behaviour is.


    4) As regards the cardstock: Of course cardstock is not food and there may not be a 1:1 correlation in wear between cardstock and food. However, cardstock does allow an empirical measurement of edge retention, whilst eliminating variables (such as cutting force, cutting skill, inter-vegetable variability.... etc) which is a whole lot better than the firmly held beliefs or intuitions that is the only other datapoint that I have seen.

    5) Larrin, please don't stop doing really useful and interesting experiments on knife steels and please continue sharing your knowledge of knife metallurgy with us.

    Now, back on topic please.
     
    Last edited: Oct 15, 2019
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  29. Oct 15, 2019 #29

    Qapla'

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    Pretty cool article; never thought of any of this in that fashion. It's a good info as to what "stainless" might really mean. I like your site, by the way.
     
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  30. Oct 15, 2019 #30

    Carl Kotte

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    @Nemo Great! Just great! And btw: are you a philosopher or something?
     
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