Quantcast
Is sharpness directly related to thickness
Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: Is sharpness directly related to thickness

  1. #1

    Is sharpness directly related to thickness

    Hi

    Quick question

    I have seen in the knives that ive purchased over the last 6 months that the thinner the knife the sharper it comes OOTB. Is this just the way it is and to get razor sharpness you need laser blades ? or can thicker knives acheive the same sharpness ?

    Alan

  2. #2
    I have a Deba that is 9mm over the shoulders. It is one of my very sharpest blades. Steel, grind and honing has everything to do with it. A laser blade will wedge less and perform better on cutting harder stuff, but for raw meat and fish a Deba will probably work just as good as a laser. There is no direct connection between sharpness and thinness of a blade. There are a lot of factors in play.

    DarKHOeK

  3. #3
    Senior Member

    Join Date
    Feb 2011
    Location
    Pensacola, FL, USA
    Posts
    3,926
    No, there is no correlation between sharpness and thinness. A crappy edge on a very thin knife will be perceived as sharp, and that's what your noticing on your OOTB edges.


    Quote Originally Posted by welshstar View Post
    Hi

    Quick question

    I have seen in the knives that ive purchased over the last 6 months that the thinner the knife the sharper it comes OOTB. Is this just the way it is and to get razor sharpness you need laser blades ? or can thicker knives acheive the same sharpness ?

    Alan
    “Ignorance more frequently begets confidence than does knowledge.”

  4. #4
    Thickness doesn't control sharpness, it controls cutting ability.

  5. #5
    Senior Member Citizen Snips's Avatar
    Join Date
    Mar 2011
    Location
    St. Louis, MO
    Posts
    454
    sharpness is sharpness.

    thickness affects performance in certain tasks
    It's like my ol' grandpappy used to say; "The less one makes declarative statements, the less apt he is to look a fool in retrospect"

  6. #6
    Literally speaking, yes. It is exactly correlated.

    Because "sharpness", as defined, is the ability to cut with ease. Thinness behind the edge improves cutting efficiency, by way of directing stress/pressure over a smaller overall object. This is why Straight Razors are so thin--because it allows them to have the bulk of the pressure applied over a smaller, more directed area, meaning you need less pressure to cut hair(which is good when pressure is being applied to your face).

    As far as knife performance, thinness is just one way of producing a knife that gets through food well. Essentially, by making a knife very thin, you can do one of two thing:
    1. Drop weight, and create a knife that is either balanced where you like it or simply lightweight overall, which reduces fatigue over long shifts.
    2. Skimp out on perfecting the distal taper and face bevels, because you are relying on thinness to provide efficiency. This is why Tojiro DP series is very thin--1.5mm spine thickness at the heel--thin stock, decent profile, slackbelt it, cut & ship.

    Generally, thinner means:
    Cuts better when dull
    More likely to snap when stressed sideways(not an issue in a kitchen, except the tips)
    lighter weight blade(can be good on long knives that are too front-heavy, but can make things very handle-heavy...weight on top of the edge helps cut)
    adds flex
    less steel to work with(faster sharpening, faster overgrinding, faster overheating)
    Less likely to wedge
    More likely to stick
    cheaper material stock if grinding the blade

  7. #7
    Senior Member
    Join Date
    Feb 2011
    Location
    Vancouver, WA
    Posts
    407
    A keen edge can be put on just about anything that can be ground. Years ago, I saw a demo, put on by the Forest Service, on fighting wild fires. What surprised me was all their tools, were sharpened, including the picks and shovels. The edge on the shovels, was able to cut hair and thread.

    Double bevel edges are similar to the triangular shape of an axe. If a knife is sharpened but not thinned behind the edge, the edge will get thicker and thicker. Dave notes a saying in his video, "The more I sharpen my knife the duller it gets".

    One thing has puzzled me, is that in theory thin knives should be the most efficient cutters. While they are good at making fine cuts, the thicker so called work horse or all around knives are easier to cut items such as tomatoes and proteins. I've found it easier to cut up a bag of chicken breasts for sates, with a Sugimoto 22, a heavy cleaver, then with a Masmoto KS 270mm sujihiki. I believe other forum members have experienced something similar when they have tried a thicker gyuto such as a Shigefusa or a Wattanabe.

    What the medium thick knives have in common are wide bevels. My hunch is that once the knife has gone a quarter inch in, that the thicker part of the knife starts to force the veg/protein apart. The weight of the knife also plays a part.

    At this stage of my experience with Japanese knives, I am finding that I prefer thin knives for precision work, while thicker knives for prepping larger amounts of food.

    Jay

  8. #8
    Quote Originally Posted by jaybett View Post
    One thing has puzzled me, is that in theory thin knives should be the most efficient cutters. While they are good at making fine cuts, the thicker so called work horse or all around knives are easier to cut items such as tomatoes and proteins. I've found it easier to cut up a bag of chicken breasts for sates, with a Sugimoto 22, a heavy cleaver, then with a Masmoto KS 270mm sujihiki. I believe other forum members have experienced something similar when they have tried a thicker gyuto such as a Shigefusa or a Wattanabe.
    I think it's the sticking that makes the thin ones feel less efficient. That and the lack of weight behind the edge. But mostly it's the sticking. Ever used a thick knife with a crappy flat grind? It's actually worse than thin with a crappy flat grind.

  9. #9
    Quote Originally Posted by Citizen Snips View Post
    sharpness is sharpness.

    thickness affects performance in certain tasks
    +1

  10. #10
    Senior Member Citizen Snips's Avatar
    Join Date
    Mar 2011
    Location
    St. Louis, MO
    Posts
    454
    Quote Originally Posted by johndoughy View Post
    Literally speaking, yes. It is exactly correlated.

    Because "sharpness", as defined, is the ability to cut with ease. Thinness behind the edge improves cutting efficiency, by way of directing stress/pressure over a smaller overall object. This is why Straight Razors are so thin--because it allows them to have the bulk of the pressure applied over a smaller, more directed area, meaning you need less pressure to cut hair(which is good when pressure is being applied to your face).

    As far as knife performance, thinness is just one way of producing a knife that gets through food well. Essentially, by making a knife very thin, you can do one of two thing:
    1. Drop weight, and create a knife that is either balanced where you like it or simply lightweight overall, which reduces fatigue over long shifts.
    2. Skimp out on perfecting the distal taper and face bevels, because you are relying on thinness to provide efficiency. This is why Tojiro DP series is very thin--1.5mm spine thickness at the heel--thin stock, decent profile, slackbelt it, cut & ship.

    Generally, thinner means:
    Cuts better when dull
    More likely to snap when stressed sideways(not an issue in a kitchen, except the tips)
    lighter weight blade(can be good on long knives that are too front-heavy, but can make things very handle-heavy...weight on top of the edge helps cut)
    adds flex
    less steel to work with(faster sharpening, faster overgrinding, faster overheating)
    Less likely to wedge
    More likely to stick
    cheaper material stock if grinding the blade
    kinda disagree. this would mean that a straight blade with a dull edge is sharper than a CCK with a very refined and stropped edge.

    sharpness, performance and efficiency are all different in my opinion.

    i think your definition of sharpness applies in most places but here on these forums, i would have to disagree
    It's like my ol' grandpappy used to say; "The less one makes declarative statements, the less apt he is to look a fool in retrospect"

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •