I'm Curious... would constant checking knife sharpness slightly dull the edge?

I

Iyonk

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Jan 29, 2010
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i'm not talking softer steel.. its more like CPM S35VN, 154CM or VG10..

the case:
you have sharpen your edge to be hair spitting sharp.. some time people run their fingers to feel the edge, like rubbing left to right to feel softy to check the edge bite..
since the edge is very accute, would your finger oils or skins act like some kind of reverse stropping to slight dull the sharp edge?
no its not about working edge, but would the extreme sharpness decrease?

i know in some steel, after you make an extreme sharp edge that's hair whitleing sharp, a few paper slice would take the extreme edge.
so would playing and feeling the edge with fingers might have the same effect ?
 
It shouldn't have much of an appreciable affect. If there is a noticeable amount of dulling, you likely had a "wire edge".

The keenness of an edge is more often due to the cleanliness of the apex than it is the acuteness (though that is not an absolute, it is pretty much agreed upon, explanation as to the counter argument later).
- In machine shops and on some industrial food processing equipment, I have seen 90° edges that would easily cut you due to the edge being so crisp.

The strop has an effect on the alloy due to the abrasive media imbedded in the strop surface.
Loaded leather, loaded denim, sub micron diamond dust, even bare leather has some innate silicate inclusions that will have an effect. Each of these will likely have more of an effect than your fingers.

That being said, if you are doing this a few times throughout the day to get a feel for the condition of the edge (pardon the poor pun, :rolleyes: ), you wouldn't likely notice any change from it. But if you spent 4 hours doing it constantly while binge watching your favorite show, you might see some degradation.
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If you had two edges, one at 20° inc/.035 shoulder and one at 60° inc/.035 shoulder and both had their apex deliberately blunted to the same measurable degree, the steeper edge would result in a wedging effect faster and thus be perceived as "duller", even though the apex was the same width.
(Geometry cuts)
 
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I could see it making an impact in a very specific set of circumstances. You would have to have a low corrosion resistance steel like M4 (which is pretty decent as far as tool steels are concerned for corrosion resistance), and have a body chemistry that gives you very corrosive sweat and skin oil. This would apply to around 5 or so people out there.

Realistically, you will see no appreciable difference on the edge from simply touching it, unless you happen to be Colossus, or your fingers are calloused so badly that you can strip paint with your bare hands. I have had very rare instances of light spotting on the cutting edge, and it took a handful of swipes on the strop and it was gone. Mind you this was with carbon steels. Stainless super steels can see some spotting on the grinds, but the edge is usually far more refined, usually with a semblance of polish to increase the rust resistance even more.
 
I've heard jeans can be used as a Poorman alternative

In theory, it should act the same. Stropping compound is to add a grit, which jeans has naturally. Kind of.

Canvas should work too.
 
I use a piece of paper from an old telephone book to test sharpness. If my blade will cut it cleanly and easily, then it's sharp enough for any task I would do. I don't see where that test would effect sharpness significantly. I also run my thumb down each side of the blade from back to edge to see if I have a burr, rolled edge - if not then it's ok.
Rich
 
Maybe, I have super sex smooth arms at the moment and patches on my legs from being bored while pooping.
 
which lead to another curiousity...

How much shaving your arm/leg hairs would dulling the super keen edge? they do dulling the straight razor right?
 
They do, but most straight razors have Very little meat behind the edge to support the edge. Due to this, they tend to roll Very easily. Which explains why you see barbers strop their razors regularly as opposed to sharpen them as often.

JohnB: just make sure you don't drop your knife, you might drop one piece and pick up two... :eek:
 
Cutting anything for an extended period of time will more or less dull your knive, maybe with the exception of air and water. It is just a matter of how long and how soon.
 
sharp_edge said:
Cutting anything for an extended period of time will more or less dull your knive, maybe with the exception of air and water. It is just a matter of how long and how soon.
Click to expand...

^ This....and if you're sharpening to "hair splitting sharp" that edge ain't good for much but slicing TP and "splitting hair"

You do any real work with it, and there will be no need to chech the edge, you'll know right away that it's not going to hold up for long, especially on the steel's you mentioned....
 
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