Sharpness test

[coop1957]

How do you measure the sharpness of your knives? I am not obsessed with sharpness but after sharpening a blade I like to give it a test. Usually I use a 3x5 index card and cut it long ways. I also have some 1/2 nylon cord that I like to try. If it is good and sharp it will cut without much effort.
What do you do to test sharpness?

 

[cerulean]

Lately, I've been testing sharpness mainly on sisal twine. It's pretty inexpensive and I use it a lot. The kind of edge I shoot for will push cut fairly easily through a loop of twine held in the opposite hand. It will also slice through the twine with a tiny bit of draw and very little pressure, but it won't slide or slip.

 

[Fonly]

nice thin slices on a piece of paper.

 

[Alberta Ed]

If it shaves arm hair above the skin it's scary sharp. If I just wave it over a tomato and the tomato falls into even slices out of pure fear, it's really, really sharp .

 

[FlyingMuskrat]

I use paper...both newsprint and heavier papers.

 

[Cougar Allen]

 

[Jamesh Bond]

Cigarette paper is the ultimate test! Though, with a thick blade or obtuse grind, even if it's hair popping sharp, it won't cut smoothly.

 

[cutlerylover]

Cigarette paper is the ultimate test! Though, with a thick blade or obtuse grind, even if it's hair popping sharp, it won't cut smoothly.

I have used smoking papers (EZ-Widers) before to test thin blades like on my SAKS...newsprint for bigger thicker blades...

 

[stdlrf11]

Here's how I do it. Plain old yellow legal pad paper.



stdlrf11

 

[AR fan]

I sharpen mine until it will pops hairs without touching skin.

 

[roughedges]

On most of my knives I look for a good sharp rather coarse edge that is sharp enough to turn magazine subscription inserts into slivers and shave my arm smooth at the skin. On most of my knives, I find a polished, hair poppping sharp, edge to be counterproductive.

 

[Joe Talmadge]

I tend to test a bunch of different ways for my EDC folders, since they're used in such a general-purpose way.

One test I do religiously that I don't see anyone else doing: I take some 1" hard poly rope and do a hard slice, then see how deep the slice is. While I don't cut a lot of poly rope in real life, I've found that this test is a fine measure of how well the knife will slice in general. From doing tihs for years, I have a sense of what constitutes good slicing performance.