How sharp, is sharp,and how to tell???

[Kai Winters]

I've never been satisfied with the level of sharpness from any out of the box knife I own...they were sharp but not sharp enough.
I've learned how to sharpen a knife to a hair whittling edge but I don't put that fine an edge on all my knives. I purpose sharpen them...my garage, yard work, hack stuff without thought, inexpensive Gerber folder gets a "sharp" edge but that is it.

If I can push the blade across the grain of phone book paper without it catching it is sharp enough for me. That is also hair splitting and shaving sharp. That is also a polished edge...I like the look of a polished edge a lot.

 

[jdm61]

How sharp is sharp? VERY sharp. I had the opportunity to compare the edges on two pretty much identical custom W2 kitchen knives that Steve Fowler had at Blade. One was sharpened VERY sharp using Japanese natural stones and the other was then tortured to the limits of human endurance and patience with diamond honing sprays up to the 160,000 grit range applied to a plain balsa block and then a non-abrasive cloth covered strop and you could tell the difference just by feeling with your fingers.......LIGHTLY AND GENTLY FEELING, mind you. No factory edge is ever going to come close to either of those IMO.

 

[edctac]

This is my 561 after a pass on the paper wheels, I'd say she's sharp

 

[grybsh7]

After sharpening or stropping I like to run the blade through my arm hairs, without touching my skin and if it pops hairs that is sharp enough.

I sent this BM 710 with a M4 blade to knifenut1013 to have him put a mirror polished edge on it. It turrned out pretty sharp.

Jason's pic

 

[Ed G]

… Didn't feel it + Blood = Very sharp …

I have definitely experienced that one - and the ER doctor commented on how clean the cut was. "Sharp knife" he said. Then I noticed the clip on the pocket of his scrubs - couldn't tell for sure, but I think it was a Benchmade clip.

The knife that caused my cut? Spyderco ParaMilitary 2 (ultra fine sharp maker rods and a leather strop).

~ Edge

 

[Piper Maru]

You know you have a sharp knife when even if you are holding the handle you still can kinda feel the edge.

 

[Bill1170]

This is exactly how I test my sharpness before putting that puppy in my pocket. My dad taught me this when I was a kid and I've done it ever since, super easy and quite reliable in determining working edge...

Yes my father taught me the thumbnail test as well. It is extremely handy for quick assessment.

 

[TheSharpStuff]

To me the level of "oh yea" type sharpness is when it will pop hairs of my arm, I am not a good sharpener by any means but I have played with some very shallow bevels on my victorinox tinker, I put around a 10 degree edge on the main blade, then went to a medium ceramic rod then a fine then stropping on a belt with aluminum/mag polish, it will pop hairs of my calf without having to touch the blade to my leg and shave facial hair as good as a razor, to me thats crazy crazy sharp. I wont carry a knife if it doesnt at least push cut through note book paper. But sharp is one of those words that you cant define.