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How you know it's sharp

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Shinob1

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What tests to you all use to determine if our knife is sharp enough? I know of the paper test, but outside of that I'm not sure how I can tell I have a sharp edge or perhaps just a grabby wire edge.
 

Eamon Burke

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Cut what you are going to be cutting with it.

There is just no substitute. I mean, I will push cut paper, rub it on my arm(I used to shave hair, but then learned that I just know how the edge feels on my skin as a side effect of doing it a lot...plus there's no hair there anymore), feel it with my fingers, etc...but the proof of the pudding is in the eating.
 

ThEoRy

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Push cut paper without slicing at different parts all along the edge. Push cut ripe tomato with no pressure. Shave arm hair.
 

slowtyper

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yeah I like the paper test because I can test all along the blade and see which spot needs more work. As for when it is sharp enough to stop, you kind of just know. It really doesn't take much to get it sharp once you get the hang of it.
 

SpikeC

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Balance the edge on your tongue, if it falls through it's sharp!
 

Crothcipt

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Forget that. Its called the how deep test. You set knife edge on thumb and pull very fast. If you see bone you win... err... its sharp.:justkidding::sarcasmalert:
 

EdipisReks

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Cut what you are going to be cutting with it.

There is just no substitute. I mean, I will push cut paper, rub it on my arm(I used to shave hair, but then learned that I just know how the edge feels on my skin as a side effect of doing it a lot...plus there's no hair there anymore), feel it with my fingers, etc...but the proof of the pudding is in the eating.
x2

Colin's folded paper cut test is a good one, though.
 

mpukas

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I think any test that you like is fine - push cutting paper, shaving arm hair - as long as you use the same test so you can develop a refence point. The important thing is to pay attention to HOW it cuts, not just that it cuts.
 

Bill Burke

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if you can cut a strip from the edge of a sheet of paper that is thinner than the paper is thick your knife is sharp!!!
 

EdipisReks

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if you can cut a strip from the edge of a sheet of paper that is thinner than the paper is thick your knife is sharp!!!
hmm. i don't know, it would depend on the composition of the paper.
 

memorael

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I just cut stuff and either fail or not, cutting paper and what not has lead me to wire edges and other stuff... try getting through service with a knife duller than a spoon, scary stuff.
 

jmforge

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Cut the gum strip cleanly off of a very thin cigarette paper, then stand another paper up on it's end folded and see if you can slice it half clean with one swing.
 

jmforge

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That would tell you that the edge is not only very sharp but very thin!! :biggrin:
if you can cut a strip from the edge of a sheet of paper that is thinner than the paper is thick your knife is sharp!!!
 

Pabloz

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Skiving Tissue2.jpgTissue Thickness2.jpg

I think this might be close to what Mr. Burke is referring to.
 

quantumcloud509

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I listen to the knife as i run my finger tip across the blade at various points. Sound is good. Danger is fun. Blood is bad. I agree with the other guys...nothing better than to test it on the line.
 

Taz575

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I cut a paper towel. I hold the paper towel between thumb and index finger and make slices down the paper towel. When it's very sharp, I can cut across the paper towel instead of down the paper towel :) Or I use receipts (the thin printed waxy paper kind), envelopes or the brownish grey paper that people use when shipping stuff to you. Got lots of that! But the paper towel shows me the best how sharp the knife is.
 

zitangy

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I use yellow pages paper.. there should be one around. thin enough, for cutting through sheets.. How it cuts ( eyes) Sound ( ears) adn feel of the cut for smoothness ( touch) adn if you really want to see how good it is, should be able to cut through a corner of the whole phone book.. smoothly in one push cut; with thumb on the spine for more push power. ( definitely not a pinch grip)

Yellow pages ....Also good for stropping.

You have to engage more than one of your senses to do anything well.. most applicable for sharpening too...
Eyes.. smoothness of cut adn the cut on the paper
Ears: sound of the cut.. Coarse sound of smooth and quiet sound
Touch: Feel how it glides across the paper. Rough or smooth....

Have fun
D
 

Shinob1

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Thanks for the advice so far.
Yellow pages ....Also good for stropping.
Now I'll have a use for that thing! :plus1:
 

DanB

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I use yellow pages paper.. there should be one around. thin enough, for cutting through sheets.. How it cuts ( eyes) Sound ( ears) adn feel of the cut for smoothness ( touch) adn if you really want to see how good it is, should be able to cut through a corner of the whole phone book.. smoothly in one push cut; with thumb on the spine for more push power. ( definitely not a pinch grip)

Yellow pages ....Also good for stropping.

You have to engage more than one of your senses to do anything well.. most applicable for sharpening too...
Eyes.. smoothness of cut adn the cut on the paper
Ears: sound of the cut.. Coarse sound of smooth and quiet sound
Touch: Feel how it glides across the paper. Rough or smooth....

Have fun
D
Yellow pages good for stropping? Really? I've been thinking I need to get a strop. Does this really work? Or should I still go for leather?
 

Citizen Snips

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i used to do lots of things to test how sharp and how refined the edge was...cutting paper, shaving arm hair, cutting tomatoes while checking the skin very closely, thumbnail test, 3 finger test, etc.

the best advice i can offer is to constantly check using your thumb and CAREFULLY moving it up the edge making sure there isn't enough pressure to break skin. you will feel sharpness and toothyness from this. after that you just use the knife like you would normally at work or whatever tasks you use your knives for.

once you learn how you like your edge, find your means to get there with consistently. the only thing i do now is use a paper towel to check for a wire edge.

also i use newspaper for stropping. my leather strop and CR02 loaded felt just sit around. i find that it really does give me the edge i really like the most
 

Sarge

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Since I'm using it to cut food that is my final test. I do use my fingers and thumb nail to feel for bite/tooth before I finish but the only real test I use is food. Like others have said I can shave arm hair with it, but I'm not looking for it to just cut the hair it is how it cuts the hair and how the edge feels in the cut that helps me know if I'm there or not. So paper, newsprint, papertowels they are fine and dandy and can tell me things about the edge, but ultimately it boils down to how it feels with the food.
 

bieniek

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And I dont cut anything anymore. I just look for the result same as after previous sharpening.
 

slowtyper

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Yellow pages good for stropping? Really? I've been thinking I need to get a strop. Does this really work? Or should I still go for leather?
Yellow pages works quite good for stropping IMO. I went to a sharpening tutorial at a local store and he showed me this technique. Its thick and padded so it has a bit of "give" just like leather. I also don't really use my cr02 loaded strop much anymore except for deburring by cutting into the handle.
 

adletson

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Can you elaborate on stropping with the yellow pages?
 

slowtyper

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I just open up the book in the middle somewhere and use edge trailing motions to strop. I like it better than using a skinny strop because you can do the entire length of blade at once. When using the skinny strop, I never got the hang of stropping from heel to tip all at once so I would strop in sections. Hell, mid-heel, mid, mid-tip, then tip.
 

Citizen Snips

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Could you elaborate on how that helps you determine if you have a wire edge?
sure, i use a paper towel dry off the knife while im doing my final stropping on the stone. i run the towel along the edge with a little force. be sure to be very careful. the paper towel will catch on the wire edge and make it more visible because of the paper bits getting caught.

some of it is the paper towel and some from the pressure at the point where the wire edge would be. combined they make it easy to detect with a little direct light.
 

zitangy

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Stropping on the yellow pages. and then leather. The results are a little different but i can just live with teh yellow pages.... The final analysis is how rough the material is which equates to grit or roughness of the material. They produce different results.

I tend to use the raw hide of leather ( rougher side to remove wire edges)

Wire edge: Hold the knife ard arms length in front and light the light dance on the edge of the blade.. Twist the balde slightly sideways or upwards / downwards and should you see uneven glint.. that is the wire edge!.

on stones below 1200 grit, I find it easier to remove wire edge on rods with teh appropriate grit. A smooth ceramic rod shld be about 1200 grit adn some steel rods ard 800 grit.and work on the finishing stone only.

FOr Burrs: i usually try to remove it on an equivalent grit of rods.. ON my my last 2 stones 5K and 10K, I like to ensure that burrs are completely removed as it will take a long tiome to remove the burrs on a higher grit stone as the main task is polishing and very light steel removal. I also suspect that harder stones ( chosera series) are better suited to remove burrs and also harder steel knives

have fun..
 

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