Sharpness vs Cutting Ability

[Larrin]

New article on the definitions of sharpness and cutting ability, where I answer such questions as:

How is sharpness defined in the scientific literature?
Is sharpness better measured with its cutting behavior or by observing the edge?
Is a thinner edge automatically sharper than a thicker edge?

https://knifesteelnerds.com/2018/08/06/sharpness-vs-cutting-ability/

 

[danbot]

Thanks for another interesting article Larrin! Does anyone run similar tests for chopping ability?

 

[ScooterG]

Thanks for another interesting article Larrin! Does anyone run similar tests for chopping ability?

Didn’t that guy get banned?

Thanks for the article Larrin

 

[Larrin]

Thanks for another interesting article Larrin! Does anyone run similar tests for chopping ability?

I haven't run across anything though I haven't yet made a specific effort to look.

 

[TheEdge01]

I’m not a scientist, but if it cuts cleanly and easily, it’s sharp in my opinion.

 

[Larrin]

I’m not a scientist, but if it cuts cleanly and easily, it’s sharp in my opinion.

Sharpness is binary? It's either sharp or dull?

 

[TheEdge01]

Sharpness is binary? It's either sharp or dull?

Please keep in mind, this is just the opinion of a backwoods county boy. Any knife will cut if it is indeed sharp, but a knife with a thin hollow grind will slice better than a scandi grind. I do my usual paper cutting/arm hair shaving tests to measure the level of sharpness.

 

[Larrin]

Thanks for sharing your experiences.

 

[MolokaiRider]

Great test and data. I also experience less media stiffness on a more blunt edge for most cuts. Meaning... the media being cut will deflect more on a duller edge than a more acute edge.

It feels like once the initial cut is started, geometry from the secondary grind becomes a major factor in the continuation of the cut.

It’s interesting in your test how the media being cut presents an enormous amount of variables as well.

I wish my tiny brain could digest your work with better grace, but I will keep re-reading and hopefully I can absorb more of the data.

Thank you again for the great read!

 

[Mo2]

Some have found this tester to be inconsistent for sharpness testing.

 

[Hickory n steel]

Anyone seen that new sharpness tester thing ?
You put this string in it and it measures how much pressure it takes to cut through it which gives you an idea of how sharp your knife is i guess.
I saw a video about it on YouTube, but don't remember who's video it was or I'd link it.

 

[Kbrasmodeler]

That's not new. Did you read the article? He mentions this as a standard sharpness test.

 

[Alberta Ed]

I measure sharpness by tossing a silk scarf into the air and letting it drift down onto the upturned edge of the blade. If it falls in half evenly, leaving no trailing threads, it's sharp.

 

[Hickory n steel]

That's not new. Did you read the article? He mentions this as a standard sharpness test.

I missed that as I didn't click any of the linked videos.
I figured the one you can buy for home use was a new thing.

 

[Larrin]

Some have found this tester to be inconsistent for sharpness testing.

I don’t see anything in the video that calls the tester into question. Most tests have potential for human error and this tester requires human hands to work.