How to quantify knife-edge sharpness

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Quantifying knife-edge sharpness remains a challenge, as sharpness is subjective and difficult to measure precisely. The discussion suggests grinding the edge until a burr forms and then removing it, as this indicates optimal sharpness. The participants emphasize the importance of creating a prototype to evaluate how well the blade retains its sharpness over time. The blade in question is made from CPM-S90V steel, known for its quality in knife-making. Ultimately, clear communication with the machine shop about the burr removal process is essential for achieving the desired edge quality.
mooktank
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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?
 
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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.
 
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.
 
violin_writer said:
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.

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.
 
cool...

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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