Looking for ways to tell if a knife is sharp.

[JeFF D]

I got a spyderco sharpmaker and I can get my knives shaving sharp quite easily, but how do you tell if your knives are shaving sharp without actually having to shave. because as my knife collection grows I seem to be getting random bald spots on my arms and legs its starting to become more and more noticable

I know of using your thumb but I cant reliably tell that way. Are there any other good ways of telling if your knife is really sharp or not.

thanks
-jeff

 

[Brass]

Find your friends or co-worker to test the sharpness of the knives for you! Some of my friends have random bald spots on thier forearms. The trick is to get them into knives and then show them the sharpmaker. They will be more than happy to shave their arms for you. LOL
Another way to tell if your knives are sharp is to LIGHTLY touch the edge of the blade and see if it "stick" to the skin.. If it sticks and leave a thin white (or red) line on your skin it is sharp enough for most task.
I got the sharpest edge from using a spyderco sharpmaker and then a leather strop.

 

[CWL]

I've been told that you can drag a blade perpendicularly across your thumbnail and it should smoothly create a single curlicue of nail.

Shouldn't skip, jump or scrape little bits off.

Don't rightly know if this is true since all of my (handstropped) blades can do this.

 

[Joe Demko]

After a while, you learn what a really sharp edge looks and "feels" like. There is a cerain visceral satisfaction, though, in watching the hair pop off your arm.

 

[scottgun]

I use a piece of paper, a really sharp knife will slice straight through with out grabbing or tearing. Use the whole length of the blade to make sure its uniform.

 

[fatboyclone]

I've been told that you can drag a blade perpendicularly across your thumbnail and it should smoothly create a single curlicue of nail.

this is the method that i use

 

[Ol' Badger]

Thanks for the tips. My Cat will be happier now!

 

[bubbygator]

I've always used the thumbnail... but a little differently from above. I lightly rest the blade on my nail & try to move it perpendicularly. If it catches at the start rather than sliding, it's sharp enough for me.

 

[CWL]

Using paper to test how sharp a knife is, is good way to make sharp knife into a dull one.

 

[5ptdeerhunter]

Hey don't give Jeff D any ideas about making me check the sharpness of his knives for him. I don't have any noticable bald spots. And I want to keep it that way.

 

[Penman]

Lay the edge against your hair at a slight angle and push down gently. A sharp edge will grab the hair and not slide. Ease up on the pressure as soon as you feel it grab, or you'll look like you got a cheap haircut.

 

[Mikul]

I usually touch the blade to the edge of one of my hairs. If it splits neatly in half, it's sharp enough.

Acutually, I rest the blade on a fingernail held at a 45 degree angle. If it catches, it's fine.

 

[SAWBONES]

Many edges will "pop" hair. That doesn't mean that they're necessarily all that sharp, though they may serve for many purposes.

My favorite test of a well-sharpened edge is to lay the vertically-held edge onto my 45 degree-angled fingernail.
Every single milimeter of that edge, tested this way, should stay put, that is, the slightest touch of the edge to the nail, under the influence of only the blade's own weight, should hold the knife in place.

FWIW, the Edge-Pro sharpening system is the best I've found.
It provides consistent control of the relationship of edge and stone along the whole length of the edge.
It's FAR superior to any variety of "crock sticks", such as the the Spyderco Sharpmaker system, or any of the several popular alternative guide systems like those made by Lansky. I own all of those, as well as several others, and found the Edge-Pro to be the best of all, plus you can adjust the angle of the edge as you sharpen.

Best.

 

[coldshot03/04]

I agree with what Golgo-13 said.

 

[Sir Galahad]

Bald spots on arms=Knife Lover's Mange.

 

[gunsmith]

dont try this method