What's the secret to sharpening a knife?

How about I reshape my edge at a sloppy 12 to 16 or 17 degrees. Not consistant at all I'd say. Then I do my sharpening at 18 to 22/23 degrees. Cliff sharpening doesn't have to be difficult. Holding an exact angle isn't necessary. My example is a exsteme one but shows my point. The final angle and and back bevels do not have to be perfectly flat to be sharp. Some will even argue that flat bevels aren't even as good, but thats not really my point. I'm saying that most don't sharpen, grind, enough and that is why they aren't getting sharp. I'f you aren't hitting the very edge it doesn't matter if your holding an angle or not.
 
db said:
The final angle and and back bevels do not have to be perfectly flat to be sharp.
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Of course not, all that matters in regards to sharpness is the last micron of the edge, the rest of it doesn't cut anything, it just effects the wedging forces on the blade similar to the primary grind.

However getting that last micron well shaped is much more efficient the more consistent the pattern from one pass to the next and the less the systematic variances the lower the number of passes needed. The pattern can be flat or convex, it doesn't matter as long as it is consistent.

And yes if you freehand long enough then this will become very natural, and you will eventually get to the point where you don't think about angles at all and just go by feel. Of course angle control matters a lot if you use different steels because some edges will crumble at 10 degrees and others are fine at five.

Lee discusses this at length in his book on sharpening as one of the three main reasons for guides, different steels require different angles, as do different knives for different tasks. The other reaons being efficiency as noted, and the tendancy to over increase or use a *natural* angle when resharpening.

I'f you aren't hitting the very edge it doesn't matter if your holding an angle or not.
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You are not hitting the very edge *because* the angle is off. If you are hitting the edge consistently then obviously your repeatability is high.

-Cliff
 
Big Ugly Tall Texan said:
What is the secret?
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I think the secret is that your father found the right stone for the knife he had and he kept it sharp, he did not let it get dull. You use a fine stone to touch up the edge on a knife. You use a course stone when the knife has gotten dull and you need to put a new edge on it.
 
Cliff Stamp said:
Of course not, all that matters in regards to sharpness is the last micron of the edge, the rest of it doesn't cut anything, it just effects the wedging forces on the blade similar to the primary grind.
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The angle effects what happens when you break though the material you are cutting. That is why drill bits have a different angle depending on if your cutting through thin or thick material. If you were to grind off a drill bit straight, it would drill just fine, but it would drift off. The reason they are V shaped is so they cut straight.
 
So which freehand method would be the best? My grandfather uses a circular motion, I use a flat draw/pull, etc. How critical are the microserrations to the cutting? If they were angled toward the front of the blade I would imagine its push cutting power would be more effective than its hair removal.
Straight down with the grind would indicate good slicing but less effective shaving as it would bite easier, etc.
 
GFarrell3 said:
So which freehand method would be the best? My grandfather uses a circular motion, I use a flat draw/pull, etc.
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If you go to a really fine finish, then it doesn't really matter, however if you leave the edge coarse then the problem with circles is that they can leave scratches running along the edge which will weaken it significantly.

How critical are the microserrations to the cutting? If they were angled toward the front of the blade I would imagine its push cutting power would be more effective than its hair removal.
Straight down with the grind would indicate good slicing but less effective shaving as it would bite easier, etc.
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You can see exactly these effects by altering the angle of the micro serrations, I tend to keep them at 90 because it allows equal aggression on slicing either by pulling towards you or pushing away from you.

-Cliff
 
On coarse edges I like to have the scratchs at about a 45 slant towards the tip. For me I have more power pulling towards me and less pushing it works like a saw. Very good question I've wondered if I was the only one who wondered about scratch paterns.
 
i choose knives that i can sharpen and keep sharp easily. i find it makes more of a difference that what equipment i have, or even the quality of the blades.
 
GFarrell3 said:
So which freehand method would be the best? My grandfather uses a circular motion, I use a flat draw/pull, etc. How critical are the microserrations to the cutting? If they were angled toward the front of the blade I would imagine its push cutting power would be more effective than its hair removal.
Straight down with the grind would indicate good slicing but less effective shaving as it would bite easier, etc.
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GF- no matter how well the blade is sharpened and stopped/honed there will always be some micro-serrations. It is just the nature of steel.

There were some real good electron microscope pictures of edges and it is amazing how rough they are at that level.
 
The Razor Edge Book Of Sharpening, by John Juranitch, took the mystery out of sharpening for me. Before that I read many posts, articles, theories, etc., about sharpening and tried several devices, aids, methods, etc. There was a lot of great info in all this, and I learned a lot, but I still never got the "big picture". I wanted to understand basic sharpening theory and technique but couldn't see beyond all the details, some of which were conflicting.

The book made understanding sharpening clear and simple. It has a lot of good drawings and photos to make it even easier to understand. Even though the book was written over 20 years ago it's still very relevant, I think. I've seen it recommended by several people who are way more advanced and knowledgeable about sharpening than I am.

My goal is to learn how to freehand sharpen well but, regarding sharpening devices, the Sharpmaker is the best for what I need. I haven't tried every single device but for speed, simplicity and ease of use, quick and easy assembly and disassembly, very few parts, almost no learning curve, fairly low cost, compact package, low maintenance, etc., I haven't found anything better.

Everybody has their own sharpening needs and goals, though. Fortunately there are several excellent tools on the market to help people attain them.
 
I support the idea that Jeff Clark, Crayola, etc should make a how to free hand video. It's not that hard, once you see it done
 
I agree Jeff, When I was a kid, my Grandpa would test a knife a couple of times on a stone to see if it would "give".
Stainless never made the cut if you will (Pun intended).
If it wasn't non-stainless he had no use for it.
He wanted a knife that would hold a mega sharp edge, and when he used/abused the edge on the farm in whatever way he deemed necessary, he didn't want to spend much time on the stone.

I love to sharpen knives, but I don't think I've ever gotten a blade to do what he could with it.

And when he looks from heaven at me with my S30Vs etc, he probably says "Lord, the boy ought to know better than that."

Man, he was good, I look so forward to seeing him again.

Seth
 
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