What’s wrong with my edge?

Lapedog said:
To be fair though you will be needing someone to hold your beer for you.
Click to expand...

My wife can hold my beer. (She only likes Lite (for the most part) and I like 'em with, let us say, a somewhat higher ABV. So, no fear on that score. :cool:)
 
LMAO, I've already tried the comb one a little while ago, so I see what they mean there. Just sounds so bizarre from the outside looking in.
now I will lightly set my thumb on the blade and go sideways and feel how it "sticks" to the skin, but never have I considered running my finger lengthwise along the blade to see. I mean, I just spent 20 minutes with it and the stones. If it wouldnt cut my dang finger by then, Ima give all these things away and just go fishing!
Actually, with the water getting warmer they might be up in the shallows anyways......hmmmmm
 
KnifeCarsen10 said:
However, when I go to do the Murray carter 3 finger test, my edge has no bite at all. What am I doing wrong?
Click to expand...
Well other than wasting time with stropping I would say testing the edge with the three finger test.

Polish on stones.
Test the knife cutting the stuff you use your knife to cut.
Honestly I can tell how my edges are MUCH better by sensing how far the edge sinks into my thumb nail.
  • Shave sharp = doesn't really "sink" but catches nicely
  • Hair whittling = sort of sinks into the face of my thumb nail a microscopic amount but none the less it is a little scary / cringe worthy.
  • Tree topping = sinks in more and my butt puckers involuntarily.
Yeah loose the strops, don't cut up your finger tips.
Happy Dog !
 
Gary W. Graley said:
Your fingers should really stay almost in one spot to feel that the toothy edge is grabbing your skin
Click to expand...
All kidding aside (well some kidding a side) Yes I GET that they want saw tooth edges and all like that for cutting . . . what ? . . . fish scales and rubarb and . . . oh I don't know what . . .

Problem is with the edges the OP and I are talking about there is no sensation and the edge just slices the skin and then you look later and your arm is off.

Madness.
 
Lol then you are doing it too hard
But as I said, that’s how it works, not telling anyone else to do it, up to you.
G2
 
@b00n Let me share a personal experience from years ago:

I hand someone my knife and warn: "be careful it's very sharp." They run their thumb down the edge a few times and say: "it doesn't feel that sharp to me." Surprised, I ask for the knife back to look at the edge myself, and while I'm doing that I hear "oh shit." I look up to see several lines of red beads forming on their thumb where it has been cleanly cut by my knife, without this person feeling a thing.

So when I read "your brain won't let you cut yourself" all I can do is laugh and shake my head.

I rarely hand someone my knife these days but if I have to I just say "don't cut yourself."
 
The three finger test as I use it (and dare I say, as MC uses it) is more of a process method.

I have a dull knife and begin grinding side for side. Once it begins to drag on the stone I will lightly use a three finger test to see if it is catching. This tells me I have either ground to a burr on one side, or am within a few passes or grinding a fresh apex, or have just ground a new apex. The advantage to using this is you don't have to squint, hold the tool up to the light, etc - you can check pretty much on the fly.

Don't just grab a knife and press your fingers into it thinking you're doing it correctly, watch a MC video and see how he applies it. He did not invent this test but he certainly popularlized it.

As the edge gets more refined on higher grit stones, it should still be catchy, this is an important part of the equation. Care/experience is needed, the more you use this test, the more it will tell you. I consider it a near perfect do-anything edge when it leaves small cut lines across the fingerprint whorls, oftentimes not immediately visible until the skin dries out. I can tell by feel pretty accurately without having to actually allow it to drag, but if I do, and the edge is right, this is the result. A wicked sharp, but catchy edge that can pressure cut and draw cut equally well. I do not normally use this test on plane irons and chisels etc, nor would it be a good idea to use this on straight razors. Though I have used it on these tools, it is better to test them on wood and hair respectively.

MC also uses it as a general test of sharpness, paraphrased "if it is three finger sticky and shaves arm hair it is sharp". Not as sharp as it might get with a more specialized finish, but in a general sense as a description of an off hand cutting tool.

Side note, I have used this test on freshly sharpened blades for the paper cutters at work, just to see if there really is an upper limit to what can safely be done, and it still works. Not that I would recommend using it this way - it really isn't safe to use on tools you cannot readily hold in your hand to carefully moderate the pressure. Bringing your unsupported fingers to a blade is not how the test is supposed to be done.
 
When the edge gets to the maximum level of sharpness, it bites with the minimal thought of moving the fingers, and of course you don’t do it. This is the part of the brain telling you to stop.
After a couple of knives
EEF6-A39-C-687-F-43-B3-AAD5-EE29-CAA57-ACE.jpg

Those lines in the first layers of skin is what the fellows are talking about.
It’s a great general sharpness test, but I cannot detect clean apex vs burr with it.
 
I could never do the 3 finger on my kitchen knives as they are really small angles on the edge.
I do the fingernail. Yeah it will stick on the nail but I do it at angles to see where it will slide.
Also I try to cut wax paper rolled up, even sharp blades will slide on rolled wax paper and when I get a really good sharpen it will just glide through it.
 
You must log in or register to reply here.
Back
Top