The Seven Secrets Of Sharpening Redux

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bgentry

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When I original wrote the Seven Secrets and posted it to bladeforums, the forum software was different than it is now. Since the upgrade all my original links seem broken and my old post isn't very readable. So I'm reposting the Seven Secrets in this new form. I've also done some very minor re-writes of some of the sections that I hope make it more understandable. It'll be broken up over several posts, as the forum won't allow the entire thing in one big post. If there's interest, I might make a PDF of this whole thing. Here's my new Seven Secrets Of Sharpening (Redux).


The Seven Secrets of Sharpening

Introduction:

The Seven Secrets of Sharpening are a set of ideas that I've slowly figured out while trying to become skilled at sharpening. I've been lucky enough to learn a lot in this forum, through watching good sharpeners working, and through my own experience. When I got the idea to write these down, I initially thought there were only 2 or 3 really important ideas. But as I thought about it, I came up with a total of seven things that I think can help almost anyone who wants to be a good sharpener. Every one of these Secrets has helped my sharpening tremendously.

I’d like to acknowledge BladeForums in general for this knowledge. Jason B, HeavyHanded, and many others have given me a lot of insight. Some of the Secrets are almost direct quotes or ideas from the people here.

Without further ado, here are the Seven Secrets:

1. Feeling the bevel on the stone.
2. The Japanese stroke.
3. Following the curve of the blade.
4. Observation.
5. Selective grinding.
6. The burr.
7. The coarse stone.
 
Secret #1: Feeling the bevel on the stone.

This is idea is simple and powerful. Let’s define terms real quick. When I say “bevel” I mean the final bevel leading to the cutting edge. So, the last facet on the side of the blade that touches the edge. This bevel might only be 1/16 of an inch wide on some blades.

Now, if the bevels are flat, we should be able to hold that flat bevel flat against a stone. In fact, we should be able to *feel* when the bevel is touching the stone in a reasonably flat way: Not with edge digging in to the stone. Not with the edge standing WAY off of the stone. But flat.

If you hold a knife with the handle in your hand and you move your wrist to angle the blade up and down against the stone, you can feel when it becomes flat. On some blades it almost seems to “click” into place. Now, if you take your other hand and press down *right* on top of the edge bevel, you can REALLY feel when it becomes flat against the stone. This feeling is so strong in some blades, that you can hold the blade in place on the stone without using the handle. Just your off hand, pressing the bevel flat to the stone. This is just an illustration of how strong the feeling in the off hand can be.

Play with this, using both hands, and you’ll certainly feel when you get the bevel flat on the stone. This is one of the primary and key ways to maintaining a constant angle. If you can feel it, you can maintain it. When I first figured this out, my sharpening consistency immediately increased.

This two handed approach to sharpening naturally leads us to Secret #2.
 
Secret #2: The Japanese Stroke

Japanese cutlery of all types, is generally regarded as being some of the sharpest available. The traditional method of Japanese sharpening hasn’t changed in hundreds of years. There’s probably a good reason for that. I find the Japanese method of using two hands to produce better results for me than using only one hand.

To give you an idea of what it looks like, and the basics, check out this video:


There are many variations of this technique. The essential parts for me are:

1. Two hands help increase control over the blade dramatically.
2. The off hand, which presses on top of the blade focuses the grinding to specific areas.
3. The off hand can be used to help with angle control, especially if the thumb of the off hand is placed on the spine of the blade.

You’ll notice that almost every sharpener using this technique sharpens with the dominant hand holding the handle for both sides of the blade. This means that on one side, the edge is facing you. On the other side, the spine faces you. You can absolutely produce fantastic edges doing it this way. But I like to do it a little differently. I like the spine facing me at all times, so I can judge the height off of the stone. So when sharpening the left side of the blade, I hold the handle in my RIGHT hand. When sharpening the right side of the blade, I hold the handle in my LEFT hand. This promotes a consistent "sight picture" of the blade no matter which side I’m sharpening. You can do it either way: Dominant hand only on the handle, or ambidextrous switching.

Let’s talk about the off hand pressure. The usual advice is to use 2 or 3 fingers of the off hand to press down on the edge bevel. The area directly underneath your fingertips will get most of the grinding action. Even if 6 or 7 inches of blade are touching the stone, the 1 to 1.5 inches under your fingertips are where the grinding will happen. This is why you see everyone sliding their fingers along the bevel as they go: To distribute this concentrated grinding force along the whole blade. This ability to focus the grinding force provides you a tremendous amount of control. It lets you grind in ways that you just can’t do using one hand only.

I sometimes use 3 fingers, sometimes 2. When I really want to concentrate on just the tip of a blade, I’ll use one finger and even roll that finger to adjust where the grinding is happening. Sometimes using only a small part of the finger tip to really focus the grinding.

Note that you can also grind more at the shoulder of the blade by moving the pressure closer to the spine. You can focus it closer to the edge by moving your fingers forward. You can experiment with your finger position and see how it affects the grinding on the blade.

Heavy Handed has a lot of good advice about hand and finger position when doing a two handed stroke. His isn’t exactly the same as a traditional Japanese stroke, but that doesn’t matter. What matters is the principles and how they work. My technique doesn’t look all that much like the videos you’ll see either. But my technique works for me and it works much better than the one handed stroke I had been doing for so many years before I tried the Japanese Stroke. It all comes down to control over the grinding on the edge bevels. The Japanese Stroke gives me a degree of control that's unmatched by any one handed approach and that makes it essential for me.
 
Secret #3: Following the Curve of the Blade

Many blades have a curve near the tip. One of the most common problems in sharpening is failure to grind this curved section of the blade correctly. Incorrect sharpening of the curved part leads to dullness in the curve, blunt tips, and ugly uneven bevels in these areas. There’s all kinds of advice about how to follow the curve, and it’s all mostly correct. But it’s really, really hard to illustrate the proper technique with words alone. So let’s take a look at the master himself, Ken Schwartz, explaining what to do and showing how to do it


This approach to following the normal line (the lines he marked on the blade) is *the* way to make sure you follow the curve of the blade when sharpening it. Of course, you should use secret #1 to help you feel the bevel on the stone, and secret #2 to give you good control over the blade as you grind along the curved portion.

Incidentally, the technique that Ken shows, also leads to ultra sharp tips. As long as you grind ALL the way to the tip and stop before you go past it, your tips will get needle sharp. Again, secrets #1 and 2 are your friends here to help you get to the tip, feel the tip, and focus the pressure where the grinding is supposed to happen.

There are many approaches to making a nice smooth bevel as you go through the curve. I like a technique that Jason B uses that I call “the swing”. A video is worth a thousand words here, so let’s watch Jason do it. (Jump to 12:13 to see the relevant part.)


Watch again on a blade with a more dramatic curve and you’ll see “the swing” in action. (Jump to 11:20 to see the relevant part.)


Watch him do both sides of the blade and you’ll see the U shape he’s describing, but turned sort of at an angle. Like the U is leaning in two dimensions both backwards and to the side. Again, the video is worth 1000 words.

Follow the curve of the blade, and you’ll make edges that are sharp from the heel, all the way to the tip, and everywhere in between.
 
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Secret #4: Observation.

Now we’re really getting somewhere! We’ve got solid techniques for controlling the blade during sharpening and grinding the entire thing the way we want to. But how do we know if we’re doing it right? Are we making nice flat bevels? Is our angle correct through the curve of the blade? In short, are we doing what we think we are?

The answer is secret #4, Observation. I’m embarrassed to say, that for many, many years, I didn’t know where I was grinding while sharpening a knife. I couldn’t point to the grind lines that I had made, or even know what they looked like. Because I wasn’t looking! It’s really embarrassing to admit, but it’s true.

So start with the obvious: LOOK at the edge bevels as you grind them. Do a little work. Stop. Look at the bevel to see what you’ve done. Now, looking for grind marks in shiny steel isn’t quite as easy as it sounds. The edge bevels are typically less than 1/8 inch wide, and most are much thinner with 1/16 being more typical. I’m going to give you two powerful observational techniques that you can use to help with this:

1. The reflected light technique.
2. The sharpie technique.

Reflected Light:

Another embarrassing thing for me to admit: An old man told me about this technique around 12 years ago. I thought he was nuts and pretty much totally ignored his advice. Around 6 or 7 years later, I read someone else giving the same advice and I tried it. Holy WOW! It works. Here’s how you do it:

Stand under (or to the side of) a bright light source. The sun works well, as do strong overhead lights. Now, hold the blade so that you catch a reflection of this bright light on the edge bevel. If you move the blade around some, you’ll find that you can reflect a nice bright line off of the edge bevel, and by changing the angle slowly, you can play this line of light along the entire length of the bevel. This will show you details that you didn’t know were there. You’ll see variations in bevel width. You’ll see nicks and imperfections. You’ll also see grind lines much more clearly.

This same technique can be used straight down on the cutting edge. Hold the blade with the edge facing the ceiling. Have the handle pointed at your chest and the point facing straight out away from you. Look straight down at the cutting edge. Now, move the point slowly down towards the floor, and then up towards the ceiling. With a truly sharp blade, you won’t see anything because the cutting edge is too narrow to reliably reflect light. But a blade with any dull spots, nicks, or other problems, will reflect light. These bright spots on the edge are your key to finding where the edge is dull and needs work. I can’t overemphasize this technique enough. It’s like carrying around a microscope. Except all you need is light and your eyes. Try this!

The Sharpie Technique:

Let’s say you’re sharpening a blade, and you’ve done 4 or 5 strokes along the whole length. You think you’ve got the angle right. You think it feels correct. But how do you know if you’re getting to the cutting edge or not? You can observe the bevels and look for the grind lines. If the grind lines are in the right place, then you’re doing your job correctly. But this is hard to do. The bevel is narrow and grind lines can be hard see clearly. So let’s make it easy.

Grab a sharpie or a marker of some sort in a dark color. Now, color the edge bevels with the sharpie so that they are no longer silver and are covered in black marker (or another dark color). Again, I’m talking about the final edge bevels of the blade that are 1/32 to 1/8 of an inch wide.

Now, do a few strokes and observe the bevel. If the marker is only being removed near the shoulder of the bevel, it means you are grinding at too low of an angle. If the marker is only being removed in an ultra-thin line near the cutting edge, your grind angle is too high. What you want to see is no marker at all. It should get removed, evenly, from the whole edge bevel. This indicates that you are grinding flat on the bevel, which you can feel using secret #1. Well, now you can SEE it too.

If you do this with enough blades, you’ll probably find that you aren’t really grinding in some spots on the blade hardly at all. This is most common at the very tip and at the choil (heel). Sharpie can help you correct this so that you hit the whole blade during sharpening.

Observation should form a feedback loop when sharpening. Do a little work. Observe. Adjust if necessary. Do a little work. Observe. Adjust if necessary. Repeat. The goal is to have the observation confirm that you are grinding correctly. Or to show you minor variations that you might want to correct. When you start doing this, you’ll have to correct often. That’s ok. It’s expected. As you gain more experience, you’ll correct less often and make smaller and smaller corrections. Don’t be afraid to apply the sharpie many times during sharpening. It’s not uncommon to reapply 4, 5, or 6 times on each side. If you want to get it perfect, you’ll want to observe often.

Note that observation is not just a visual thing. Secret #1 is actually an observational technique too. You use your sense of touch to feel where the bevel is. Touch can tell you other things as you progress. Sound plays a role also. Grinding at too high an angle produces a sound as the blade digs into the stone. Too low an angle sounds (and feels!) different.

You shouldn’t try to do ALL of this all at the same time. You’ll overwhelm yourself with too much input. But as you progress, you’ll notice things. Pay attention.

This is one of the longer explanations in this series. That’s because it’s one of the most important of all of the secrets. This one can really change sharpening for you. It did for me.
 
Secret #5: Selective Grinding:

If you sharpen enough blades, sooner or later you’re going to find one that’s more dull or damaged in one spot than all the others. This is very common, particularly near the front of the blade. People tend to use the point and the first few inches more than the rest of the blade, so it tends to be the dullest part.

You’ll also find blades where, despite your best efforts at holding the correct angle, some of the sharpie just doesn’t get removed on some parts of the blade. These areas need more work than the rest; so more grinding is required.

So the answer is simple: Grind more in the spots that need it more. It’s so obvious, I can’t believe I never thought of doing it until someone mentioned it. It’s totally ok and expected to do 10, 15, or even 20 back and forth strokes on one concentrated area of the blade.

For example, if the tip is very blunt, I might sharpen normally all the way to the tip. Then spend 5 to 10 extra strokes *right* on the tip, using my finger pressure (from secret #2) to apply the grinding force to the part of the tip I’m trying to grind. After doing repeated strokes, I’ll then do several full length strokes to blend the bevel together. Use your judgement, and Observe the blade. If you start to widen the bevel at the spot you are working on, you’ve gone too far. Blending strokes along the entire bevel, in between concentrating grinding in one spot, will help prevent you from making the bevel too wide, or otherwise making it cosmetically unappealing.

Of course you want to use Observation the entire time to check your work. Check to make sure you’re removing the sharpie. Check the bevel widths and see if they are changing as you grind. In some cases, you might be trying to increase the width of an area that wasn’t properly ground before. This is very common with factory edges, especially at the heel of the blade.

Selective grinding will save you time and steel. By selectively grinding the areas that need it, you’ll save steel in the areas that don’t. You’ll save time by only grinding in the areas that need it.
 
Secret #6: The Burr:

At this point we have a lot of good techniques. We should be able to grind a bevel very evenly and consistently along it’s entire length. We can check to see that we are grinding where we are supposed to and make corrections as necessary. There’s just one thing missing. How do we know when to stop? The answer, is secret #6, The Burr.

The burr has been discussed and detailed in a lot of sharpening literature. I’m just going to briefly cover what it is and then get to what I think is important. What is the burr? The burr is a curl of metal that forms when grinding reaches the edge. The burr is a positive indication that you have ground the bevel until it hit the apex. In most cases, this means you are done grinding on that side of the blade. Here’s a picture showing the burr forming on the opposite side from the grinding.

raising-the-burr.jpg


(from: http://www.knifeplanet.net/wp-content/uploads/2015/10/raising-the-burr.jpg)

The burr tells you that you are done grinding. Form a burr on one side of the blade, full length. Then grind the other side of the blade until you get a second full length burr on the other side. Now remove the remaining burr. This tiny paragraph is a summary of a complete sharpening of a blade. That’s it.

If there’s a “secret” about the burr, it’s this: You must make a full length burr on each side of the edge in order to correctly grind the edge bevels. Full length is the important part here. Many people, myself included, check for a burr and as SOON as we detect a burr in one spot, we switch to the other side of the blade. This is wrong. Once you have a burr formed in one section of the edge, you should continue sharpening until you can detect the burr along the ENTIRE length of the blade. Use secret #5, selective grinding, to concentrate your work on the areas that don’t have a burr yet. Do blending strokes. At some point, you will probably be grinding an area less than 1 inch wide. The burr will have formed on the whole edge, except for this one section. Continue grinding in that area until you get a burr, or that part of the blade will never be truly sharp. This is the real secret of the burr.

The three important aspects of the burr are:

1. How to form a burr.
2. How to detect the burr.
3. How to remove the burr when you are done.

Forming a burr:

This is simple. Just keep grinding, using all of your tools and techniques, until the edge bevel reaches the apex and a burr will form. Keep going until you have a burr along the entire edge from heel to tip.

Detecting the burr:

There are many, many different ways of detecting this delicate curl of metal. Feeling with your finger tips seems to be the most popular way. Here are a few for you to try. If you need help with this, seek out other resources that detail burr detection. This is a HUGELY important part of sharpening, so you want to get it right.

A. Sliding your fingers off of the edge. Move your fingers from spine to edge on the blade, trying to feel the curl of the burr digging into your finger prints.

B. Testing for sharpness, both directions. Have you used your thumb to test a blade for sharpness by moving across the edge? You can use this to detect the burr. Stroke your thumb on the edge as normal feeling for sharpness. Now spin the blade around so the left and right sides of the blade swap places. Do your test for sharpness again. Did it feel sharper one way than the other? If so, the side that felt sharper has a burr. That’s because the burr is thinner than the real edge, and it digs into your finger prints more deeply. This works surprisingly well with a little experimentation.

C. The fingernail catch. Slide your fingernail from spine to edge on the blade. When it reaches the edge, it should just slide right off of the blade. If you have a nice big burr though, the burr will catch your fingernail and stop it. It’s sort of an amazing feeling actually. This is a very positive test that you pretty much can’t get a false positive from. It either catches your fingernail and stops it, or it doesn’t.

Burr Removal:

Once you’ve raised a burr on one side, switched sides, and then raised a full length burr on the opposite side, you want to remove the burr completely, leaving behind a clean crisp edge. Again, there are many many ways of doing this. Seek out another resource for more complete directions and techniques for burr removal. I’m just going to highlight a few that I like.

A. The double angle technique. Let’s say you’ve been sharpening at roughly 15 degrees per side. You’ve formed the burr twice and you’re ready to remove it. Put the side with the burr down on the stone. Now raise your angle to roughly 30 degrees. It doesn’t need to be exact at all. Just a much higher angle than you were using. Now, do 1 or 2 very, very light strokes. Not even the weight of the blade. Flip the blade over and do 1 very light stroke on that side. If you’ve done it correctly, the burr should be essentially gone from both sides. Check and see. If some burr remains do another single light stroke on the side with the burr and check again. Once it’s gone, lower the angle back down to the original and do one light stroke per side, switching sides after each stroke. Do perhaps 3 to 5 of these original angle strokes and your blade should be done.

B. Drawing through wood, cork, or felt. Just lightly running the length of the blade through end grain of wood, a wine cork, or hard packed felt can rip the burr off. This is most useful when the burr is very small or there are just little burr chunks remaining on the edge. Notice the gray or black residue that’s left on the cork or wood. Experiment with this and see how it works for you.

C. Deburring directly on the stone. If you are very careful with light strokes, you can remove the burr fully, at the original angle, just by using light pressure and checking after each stroke. Ken Schwartz advocates doing sideways strokes, parallel to the stone (not forward, not backwards, but sideways) to grind the burr off. I’ve had limited success with this and I only mention it because Ken is exceptionally skilled. I’ve had my best results removing the burr at the original angle by doing forward strokes only.

What if you can’t seem to form a burr? Use secret #4 observation. Use the reflected light technique to see if the blade edge is reflecting light. If it reflects light, it’s dull enough that more grinding is necessary to form a burr. Reflected light (directly on the edge) is a really good way to monitor your progress. Once the reflections disappear, you are very close to forming a burr.

Learn to detect the burr consistently. Work on making a full length burr every time you sharpen. On both sides. If you’ve never formed a full length burr before, you’re probably going to be rather surprised by the resulting edge. I know the first time I did it, it changed everything for me. I couldn’t believe that I just hadn’t been grinding for long enough. My edges improved markedly once I got this figured out.

Learn to deburr fully. This can be tricky. If my example methods above don’t work well for you, seek out the advice and techniques of others. Burr removal is absolutely essential to forming clean, crisp, durable edges.

Master this and you’ll be well on your way to making outstanding edges.
 
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Secret #7: The Coarse Stone:

A lot of beginners are told to not use too coarse of a stone to start with. The idea being that they can do less damage to a blade with a finer stone. I think this advice is backwards and flat out wrong. Here’s why:

A coarse stone:
Shows grind lines more easily, thus allowing you to monitor your progress more easily (secret #4).
Allows you to make progress faster, thus preventing fatigue. Fatigue destroys angle holding ability, which makes edges worse.
A feedback loop is formed by grinding flat on a coarse stone: The edge bevels become flatter faster, thus increasing the *feeling* of the bevel on the stone (secret #1), which improves the ability of the sharpener to hold a consistent angle, which makes the overall edge better and flatter.

I think everyone should start any big sharpening job with a very coarse stone. How coarse? I like the DMT XXC, which is 120 micron, or about 100 grit. This is very similar to a Norton Coarse Crystolon (silicon carbide), which also grinds very fast I’m told. Essentially, unless you have a some really exotic super coarse stone, you should start every big sharpening job with the coarsest stone you own.

Let’s define that: A big sharpening job is one where you will significantly grind the bevels. You might be removing nicks, sharpening an abused or neglected blade, or even changing the edge angle to a lower angle. These jobs need a coarse stone. Touchups and minor sharpening don’t qualify.

Here are a few things many people, even experienced sharpeners, don’t know about coarse stones:

1. They can make really sharp edges. Something in the 220 to 350 grit range, like a DMT C, can make edges that pop hair off of your arm. I was totally shocked the first time I made a hair shaving edge from a DMT C. Now I can make an even sharper edge from the DMT C. Sharpness does not equal refinement. In other words, a fine stone is not necessary for a very sharp edge. A fine stone is only necessary for a polished edge.
2. Edges made on coarse stones can cut abrasive materials *better* than highly polished edges. In my experience, the difference between a ~600 grit edge and a ~100 grit edge, when cutting cardboard is about a 2 to 3 times edge holding difference. The 100 grit edge holds it’s edge for much longer when cutting things like cardboard.

In summary: The coarse stone is your friend. It will get you results faster, which actually means you’ll get better results because you don’t get fatigued as fast. It will give you better psychological results as well, promoting your feeling of accomplishment. This is no small task when learning a new skill. Or even practicing an old skill. Coarse stones can make very sharp edges. Coarse edges can last longer for abrasive cutting tasks.

If you don’t have a stone that’s at least ~200 grit, you need one. This is another one of the secrets that dramatically improved my sharpening. I hope it does for you too.
 
Thanks for making this available right on the forum software. There are lots of good bits on information to point people to.
 
Very well presented!
Concise, and to the point(s)!
This will be very useful to many people!

(I don't always use exclamation points, but when I do...)
 
I read the whole system again (of course I had read the first sticky long ago).
Thank you again for taking all the time and effort to hammer this out and make it extra good !
Without going off the rails on my normal stuff I have a question or comment here and there :
What is the smallest practical size blade that you find works with the two hand / feel the bevel secrets ?

What is the smallest bevel you can still feel on the stone. You have mentioned 1/16” (1.5mm) and as small as 1/32” (0.8mm). Very often I get down in the range of the latter and feel like there is no way I could detect the bevel at that width especially on a curved edge.
Yes I know the short answer : Wowbagger go try it and see for yourself.

I have done a lot of this kind of bevel detecting on wider chisel edges (single bevel) for Japanese hand plane blades and actual woodworking chisels and I find I rock on a wider bevel trying to get down to the edge and have given up on that for two reasons the swarf coming off a wide bevel over whelms the very fine pores of the finish stones and once the bevel is a little rounded I am back to failing to detect when I am on the edge and so round it more. But that is on bevels that are > 1/4”

Bur detection :
I don’t like the feel for a bur methods. The burs I tend to end up with are so fine and light that I find it is better to sight them as you did for glints on the edge but with the light source roughly behind and above my head; the spine of the knife toward the light and the light streaming down the side of the knife and off the edge. If there is a bur it will reflect light back to my eyes and I can detect the finest bur. Then check the other side of the knife. Of coarse I do this with quite strong magnification; I wear a jeweler’s visor that tilts up when I don’t want it over my eyes.

Why do it this way ?
Well once the bur gets thin enough the act of feeling for it can bend it over to the other side of the knife.

When I sharpen a side and go back and forth first one side then the other to refine the edge and the bur is getting super thin if I use the light method to detect the bur then I can go edge leading on that side to help take the bur off. I keep the bevel angle the same (I don’t go steeper) so this should work fine while feeling for the bevel. One or two edge leading very light passes on each side is then often enough to remove the bur. From there I do one or two edge trailing passes per side to refine the edge. Of course this is all done with my evil sharpening jig. When I have done the above deburing as described I know without even testing that we are hair whittling and the knife can go in my pocket (no stropping).

I strongly recommend the light method for fine bur detection; I even use it for the initial bur detection and never feel for it. If I were working where I was out side and it were cloudy or I didn’t have magnification that would be all different. I would be feeling for it like crazy but the final edge probably wouldn’t turn out as satisfying.

An important Redux !
Thank you !
I'll keep practicing.
 
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Wowbagger Wowbagger ,

Thanks for sharing the burr method you use. I found it depends a lot on the steel and abrasive, also whether it has slurry or not.

When successfully deburred at existing angle edge leading, sometimes it becomes small grainy feel on the stone. Quickly wipe it clean (both stone & blade) and check is recommended.

I don’t think the jig is evil. Just don’t want to spend $ on it if my free hand can satisfy me. Of course it won’t be as flat as jig produced edge, but I am challenged to be better each time, like HeavyHanded HeavyHanded , 1° wobble. I am nowhere near that, and not sure how much it is, but my right hand (spine facing me) is now getting more consistent compared to my left hand (I’m right handed, funny isn’t it, the weak hand is more consistent).
 
Relative to #1, another method of finding this on the fly is to, while grinding, lower the spine for a pass or two, very light, very short.

The shoulder will feel like it has more drag. Slowly elevate the spine till you don't feel that drag anymore and keep going.

When starting in on a knife unknown to me, I will often bounce back and forth between the apex and the shoulder a few times to ID the existing angle, then reset it.

On a knife with an existing angle that is acceptable, bouncing off the shoulder will help make an edge with the absolute minimum deviation you are mechanically capable of. As you come off the added drag of the shoulder you immediately feel the apex dragging - you know the bevel is darn flat, and whether there is a burr or not the edge has been apexed or is within a few strokes of being so.
 
Wowbagger said:
What is the smallest bevel you can still feel on the stone. You have mentioned 1/16” (1.5mm) and as small as 1/32” (0.8mm). Very often I get down in the range of the latter and feel like there is no way I could detect the bevel at that width especially on a curved edge.
Click to expand...

I quoted numbers for bevel width as an illustration of size. To give the reader a reference point for what I was talking about, particularly for those that aren't quite as familiar with blade geometry as many here are.

I haven't really studied bevel width versus my ability to feel the flatness. It seems to work well for me with kitchen cutlery which tends to have somewhat narrow bevels (1/16" or so).

I can tell you this though, which I don't think I really talked about enough above: When you are riding on the shoulder of the blade, it's very easy to detect with your off hand. Because when you are way too low the edge of the blade will not be touching the stone. Your off fingers will feel this pretty clearly because there will be a gap between the blade and the stone. Lowering back down, you'll know when that apex touches the stone. Getting it perfectly flat combines several sense points including how "wobbly" the blade feels as you move it. When you really have a nice flat bevel, that wobble seems to disappear and you know you've got it right.

I don't think this really completely answered the question, but I hope it provided maybe a little more info that might help someone to understand the concept and things to look for as you execute this technique.

Thanks for reading and commenting. I'm gratified that others are getting something out of this.

Brian.
 
I needed to do a little touch up on my latest knife, it is a Case Trapper in CV steel. I cut some dirty old window screen and the edge was no longer shave / catch on the thumb nail sharp. No damage though.

The Factory edge bevel width is right at 0.5mm (less than 1/32 of an inch) by actual caliper measurement.

This knife has an edge length of 3 inches, the handle length is over 4 inches (this is not a particularly small EDC). I mean what could be more average in a pocket knife for a person new to pocket knives ? A Case Trapper with a factory edge geometry ? ! ?

I busted out my Shapton Pro 5,000 bench stone and figured I would use that to try again to learn to use this technique.

I could not detect even a hint of the bevel. while holding the blade down on the stone with my finger tips and supporting the handle with my other hand.

Keep in mind this is a bevel that was already made perfectly flat because it was refined on the Edge Pro just a few days ago. If I should be able to feel the bevel this is optimum since I didn’t have to first produce a flat bevel by feel. It is already as flat as can be.

Granted the handle of this Case Trapper is quite heavy and tended to overwhelm any attempt at pressing the bevel down on the stone to the point the knife is held in place only by fingers on the blade at the stone. Although hahaha I have even lightened this particular handle by removing the Spay blade the other day.

Maybe with a knife with a really light handle it might be possible to detect the flat of this width sharpening bevel. I seriously doubt it though.

I make my living working with my hands assembling and tuning fairly light weight mechanisms that require a fair amount of dexterity and fine motor skills. Including fabricating or modifying parts by hand and hand sharpening drill bits. Not just bolt it together and go like say . . . an automobile.

I have a good decade under my belt of producing easily hair whittling edges off stones with no strops. Meaning I have a good idea of what it takes to produce a decent edge. (hahaha a sharpening jig hahaha)

My point is what hope does a person have using this method to sharpen their knife who is new to edge tools with lesser skill with their hands and a knife like the Case Trapper ? I fear they will have very little success.

I really do think you should quantify this technique and give some parameters so that unsuspecting new sharpeners know when to use this technique and when to look else where.

I could have fooled around with my own methods of hand sharpening and produced a hair whittling edge which tends more to the method Michael Christy favors; knife in one hand and stone in the other. I take it further and sight the gap between the edge and the stone while wearing a jeweler’s visor and align it so the gap just closes. It wouldn’t have been fun though. A lot of wasted motion and time spent abrading metal that was not right on the edge. I do this sort of thing when I am away from my shop and my sharpening jig but I can not recommend it . . . especially to a new sharpener looking for gratifying results.

In the end I used my Edge Pro, first with a Shapton Glass 1,000 then the 4,000. It was no challenge. That’s the way I like my sharpening. Painting a picture or playing music is one thing (individual talent and technique make a difference). Grinding edge tool edges into a practical configuration is just a process . . . and is best done with a tool designed for the task.

I’ll say it again what could be more average in a pocket knife for a person new to pocket knives ? A Case Trapper (three inch edge with a four inch handle) with a factory edge geometry ? ! ?

Newbies . . . you’ve been warned.
 
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bgentry said:
I can tell you this though, which I don't think I really talked about enough above: When you are riding on the shoulder of the blade, it's very easy to detect with your off hand. Because when you are way too low the edge of the blade will not be touching the stone. Your off fingers will feel this pretty clearly because there will be a gap between the blade and the stone. Lowering back down, you'll know when that apex touches the stone. Getting it perfectly flat combines several sense points including how "wobbly" the blade feels as you move it. When you really have a nice flat bevel, that wobble seems to disappear and you know you've got it right.

I don't think this really completely answered the question, but I hope it provided maybe a little more info that might help someone to understand the concept and things to look for as you execute this technique.
Click to expand...

ooooh kaaaaay
I'll try that.
:) :) :rolleyes: :)
 
Just did a minor edit to Secret #3 noting the time signature you should watch in the two videos by Jason. The forum software doesn't like the time signatures being coded in, so I've just written the correct times before the video so you can jump to them.

Brian.
 
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