"Shaving Sharp"-- Practical value or parlor trick?

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BubbaGump

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Oct 30, 2015
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What is your experience with this and opinions? A 'shaving sharp' steel may be a sign that a properly polished apex edge was formed. It could also mean that overly aggressive or improper sharpening created an extremely fine wire edge that was formed by a burr, which will quickly fall/wear off and leave the blade as dull as a butter knife. In either case, the 'shaving sharp' property doesn't last that long and I never really found it to be of much value for practical EDC tasks. I used to be pretty anal about it but not I no longer really use it as a gauge of when I have finished the sharpening task. I usually get to the point where the blade will cut cleanly and evenly through paper and I am good to go. Going beyond this I have found to be a waste of time as the 'razor' sharp edge doesn't last long enough to present any real extended practical value.
 
You are right that the sharper a knife is, the faster it gets dull. So what value does "shaving sharp" have? Well, at least the knife can be used to shave :D When a knife is being used to cut cardboard, e.g., I agree with you that shaving sharpness is neither necessary nor an optimal choice.
 
I don't think you would want to (or even could) shave with a wire edge.

That said, if people like to give their blades a mirrored "razor" edge, and that makes them happy, who is to call that a "waste of time" or "parlor trick"?
 
I agree. I'm the same way. I used to concern myself with keeping my knives, especially my users, as close to shaving sharp as possible. Now, I hit my users with the Sharpmaker when I think about it/feel like it and almost never with my others. And as long as they cleanly shave/cut paper, I call it good. No worries, really. All my knives are excellent steels like ATS34, 154CM, CPM S30V, CPM S35VN, D2,...so they stay quite reasonably sharp/user-sharp for a long time.
 
I simply have no need for an edge that sharp.

Even 'phonebook paper' sharp is more than enough for me.
 
sharp_edge said:
You are right that the sharper a knife is, the faster it gets dull. So what value does "shaving sharp" have? Well, at least the knife can be used to shave :D When a knife is being used to cut cardboard, e.g., I agree with you that shaving sharpness is neither necessary nor an optimal choice.
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Depends what you mean by "sharper." Do you mean "more refined" or "thinner edge angle"? A polished 35 inclusive wont get duller faster than a 35 inclusive without a mirror polish.
 
My edges are "razor sharp" at 300 grit. You don't need to polish an edge to make it sharp, just make sure you remove the burr. Sharp is sharp, how far you refine it is up to you.
 
Shaving sharp is just a benchmark where I stop.

It's in between printer paper and phone book paper sharp.

Also something to shave is always with me. Paper I'd have to get somewhere.
It's an easy test and not that hard to reach that level. If there's an easier test I'd be interested to hear.

Also sharp doesn't mean dull fast. Many people mistake sharp for thin. I've seen knives which have roughly an 45 degree edge and cut magnesium. They where sharp and cut easily cut through a fingers skin without much effort.
 
sharp_edge said:
You are right that the sharper a knife is, the faster it gets dull. So what value does "shaving sharp" have? Well, at least the knife can be used to shave :D When a knife is being used to cut cardboard, e.g., I agree with you that shaving sharpness is neither necessary nor an optimal choice.
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I always thought that the more polished the edge, the less resistance and wear, but I have not done or researched cut tests extensively. Also, my knives dont shave well when they have a burr. Every once in a while I'll get an edge I think is sharp and was a wire, but usually it's not a problem as I finish on a fine stone alternating sides w a light touch.

Also, my knives are shaving sharp by the time I've finished with course grit, but refinement makes it smoother.
 
Jason B. said:
My edges are "razor sharp" at 300 grit. You don't need to polish an edge to make it sharp, just make sure you remove the burr. Sharp is sharp, how far you refine it is up to you.
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I agree, sharpness is a shape.

A while formed apex shaves at almost any grit.

Some round there apex when moving up to higher grit

Some never form a crisp apex due to not making a burr

Some don't properly remove the burr an shape a wire edge.

There are some pit falls involved

But my edge are razor sharp as a consequence of just being sharpened well.
It doesn't take much effort and a good edge lasts longer.
 
correct me if I am wrong:

- for the same knife, meaning other factors are the same, a thinner edge is sharper than a thicker edge.

- still for the same knife and this time with the same edge thickness (i.e., same dps), a refined/polished edge is sharper.

- I thought "shaving sharp" always means to shave human hair (arm, leg, beard, etc.). By "shaving paper" do folks just mean cutting paper?

And just add to the confusion, what is the difference between shaving hair and poping hair? is it just a degree of pressure you push the knive through hair?
 
sharp_edge said:
correct me if I am wrong:

- for the same knife, meaning other factors are the same, a thinner edge is sharper than a thicker edge.

- still for the same knife and this time with the same edge thickness (i.e., same dps), a refined/polished edge is sharper.

- I thought "shaving sharp" always means to shave human hair (arm, leg, beard, etc.). By "shaving paper" do folks just mean cutting paper?

And just add to the confusion, what is the difference between shaving hair and poping hair? is it just a degree of pressure you push the knive through hair?
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Shaving sharp means to remove hair w/o damaging the skin.
Shaving paper means it's sharp enough to shave paper off the the piece of paper...think "peeling a piece off like the skin off an apple."

A thinner edge does not mean sharper, just thinner. Sharpness a subjective term. You can have a an edge that shaves hair and a thinner edge that shaves hair but they are both "shaving sharp." In general a thinner edge is more likely to be subjected to damage, but is a better slicer. For example, it takes a thin edge to shave paper due to the geometry of the cutting action.

A polished edge does not mean sharper, just polished. A polished edge does not always cut better. For example, if you are cutting rope, you don't want a polished edge you want a "toothy" edge i.e. coarser. In general, a coarser edge has more utility. For people who carry slipjoints, many will have a coarse edge on the big blade but a polished edge on the small blade, but both edges are "sharp." In general, for routine utility use, a polished edge is not needed, but then the people who love Rockstead knives would disagree :)
 
From what I have observed, poor sharpening (or technique) wears out a blade quicker than anything.
Put a good edge on it and maintain it. I touch up my edc every 2 weeks or so.
 
Jody744 said:
From what I have observed, poor sharpening (or technique) wears out a blade quicker than anything.
Put a good edge on it and maintain it. I touch up my edc every 2 weeks or so.
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Quite true. The Sharpmaker is good for that reason as it removes minimal material, yields a very satisfactory edge in a reasonable time, and does it fairly quickly with minimal setup.
 
None of my EDC knives leave the house until they are capable of shaving arm or leg hair. No time is wasted if you have the proper equipment and knowledge. I don't recommend this to other people as most are not accustomed to using a very sharp knife and usually cut themselves.
 
Personally, I vastly prefer my collector-knives (all fixed blades) to be as stupid sharp as possible...but ya, the few that I designate as users, do spend most of their lives in a state of usable sharpness & not necessarily hair popping, if that makes sense.

I suppose there are a couple of reasons I prefer the knives I EDC for light duty &-or display in my home to be super sharp: I enjoy seeing how sharp all of the custom makers I work with/buy from will deliver their creations...it's typically not the best of signs to me when I receive a custom knife that can't cut paper very well. I also enjoy showing my knives off to family & friends, & the one thing that most non-knife nuts do is "check" for sharpness, & I'd rather they be blown away than left saying, hmm, that needs a sharpening. And finally, I don't enjoy sharpening knives, so since I do EDC most of my knives, even my bigger fixed, I perform only light tasks with my really nice ones that I want to keep pristine, so an initial very sharp edge (with a great knife steel & a great HT), is going to last me for years.

And again, the few that I do use for heavier stuff, I keep them sharp enough & I tend not to miss the hair popping-ness...save for some slicing tasks. And just to touch on the OP's title of Practical value or parlor trick - I'd argue that impressing the humans in my life with my crazy sharp knives is practical value....to me.
 
sharp_edge said:
correct me if I am wrong:

- for the same knife, meaning other factors are the same, a thinner edge is sharper than a thicker edge.

- still for the same knife and this time with the same edge thickness (i.e., same dps), a refined/polished edge is sharper.

- I thought "shaving sharp" always means to shave human hair (arm, leg, beard, etc.). By "shaving paper" do folks just mean cutting paper?

And just add to the confusion, what is the difference between shaving hair and poping hair? is it just a degree of pressure you push the knive through hair?
Click to expand...

These are some great questions IMO. Much of this is relative. So shaving sharp means just that, able to shave hair. "Hair poppin" is kinda slang I think, but I've noticed when an edge is really good for shaving, the hair literally pops. You can hear the sound and feel it in the draw. So maybe that's what people mean. Sometimes a knife will need to be pressed a little more or take more swipes, but will still shave clean. I'd consider that barely shaving sharp, but far short of hair poppin.

And different hairs have different shavability. So as someone else said, I test my degree of sharpness through this as well. My leg hair is easy to shave. If my knife cant shave a clean patch in my leg in one pass, its not sharp enough.

My arm hair is much finer, much harder to shave. I don't always make my knives sharp enough to shave my arm hair, but when I have time I do. It really doesn't help much in edc, but its fun. Also that much more satisfying when opening things with that clean glide that you can't even feel.

Now facial hair is a whole nother story! There's only been 2 times I've gotten any of my knives sharp enough to actually shave my face and they didn't feel too good. And that's fine, I'll get to continue to enjoy the experience of learning how to sharpen in the quest of achieving "!!ultimate sharpness!!"
 
I would probably draw the line at actually trying to shave with a knife. Although its semantics and a razor or shaving blade is technically a knife blade, there is a reason they exist and people don't put on the morning coffee, lather-up and grab their pocket knife, even a very sharp one. Although the phrase is often used as a metaphor for extreme sharpness, the only thing as sharp as a razor is another razor. They make them for a reason.
 
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