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How to quantify knife-edge sharpness

  1. Feb 12, 2009 #1
    I'm designing a cutting blade and I'm working on the drawing right now. I have the geometry and surface finish spec'd but I was wondering is there some way to quantify sharpness of an edge? Can I just say to grind the edge until a burr forms and knock the burr off?
  2. jcsd
  3. Feb 13, 2009 #2
    I believe I've heard of this before. The best steel blades are melted and folded... melted and folded--- look at the samurai blade.

    What you said sounds right, just make sure have some sort of edge to begin with. I think I the actually cut the burr off with another knife if I remember correctly.
  4. Feb 13, 2009 #3
    Sharpness I don't think can be quantified. However, you might would want make a prototype and check how well it holds it's sharpness--- that is the true test.
  5. Feb 13, 2009 #4
    We're making the blade from CPM-S90V, a particle metallurgy steel. It makes a very good blade and we've done some testing with a blade that's not as sharp as it could be.

    I just want the machine shop to be able to make the part properly.
  6. Feb 13, 2009 #5

    I think you just tell them to knock the burr off, because when a blade has a burr it's as sharp as it can get. At least that what I saw in "how it's made" or a show like it with kitchen knives.
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