# A few questions re: Edge Pro stones and What is the ~ factory bevel of K-Sabatier carbons?



## betowess (Feb 14, 2013)

I'm new to this nice forum, and have been enjoying reading various reviews from BDL and others and the article on Japanese Knives 101 by Chris Lehrer etc. Its been fun reading and researching this material, which is a bit daunting on first exposure.

Anyhow...

I had bought an electric chef's choice sharpener online, but didn't really like it. Though it worked pretty well, it seemed to dull the tips and was kind of burpy / noisy and burnished the sides etc.

So...after reading around this forum, I recently I ordered a Edge Pro "essential" kit from CKtG. It has the basic Shapton glass stones which are the 500, 1000 and 4000 grits, which I hope will do me fine with my Sabatier carbons - which I absolutely love.

*1.* So here is my first query... I know I will be sharpening some friend's _really_ dull knives. So I also ordered a couple of Edge Pro OEM 220 grits, thinking they were course grits and hearing from Mark that they don't last that long. But now I have read that the Edge Pro stones are rated on a different scale, so that is really just a medium grit stone, right?

So would it be smarter to get the course DMT 6" that fits on the EP? Or what might you recommend to get a decent bevel started on my friend's _scary _dull knives?

(I have a DMT "Duosharp" course blocks, but its the 8" x 2 & 5/8" and I don't think it would fit on the Edge Pro. And I don't want to waste time with starting the wrong bevel angle free hand anyhow...) What do ya think??

*2*. My second question. Just to make it easier, when I first sharpen up my new carbon Sabatiers, does anyone know what the factory bevel is? I'm guessing its in the 18 to 20 degree range, but I haven't a clue. They are already pretty sharp and so I don't want to change to a new bevel and make more work than necessary.

Also, I use a polished F-Dick's Packhouse steel, which seems to work great the few times I have gently steeled any of the Sabs (or other knives for that matter). Any opinions on this steel?

Thanks in advance to anyone helping with these questions.

And thanks for all the great reviews and posts and articles etc. by BDL , Phaedrus, Chris Lehrer and others.

Its been great reading, and well written too!


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## betowess (Feb 14, 2013)

Thanks Benuser, That is good to know on the polished F- Dick steel, I kind of thought it worked very well, but good to get a confirmation and I was during some real gentle strokes.

Regards the bevels, I'm not too confident yet with free-hand but I appreciate your suggestions. I do want to get some feedback from folks who know about the EP stones. Hopefully someone will respond.

I guess this knife thread area got moved, so it might take a bit  before everyone figures out the navigation to this part of Chef's Talk... it took me a few clicks to get here... Thanks again.  I can call Mark at CKtG if I need to I suppose...


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## boar_d_laze (Feb 13, 2008)

The most acute bevel a carbon K-Sabatier or similar Sabatier (like a T-I, Mexeur et Cie, etc.) will support without collapsing too frequently is 15* with very little asymmetry.

The alloy is very soft and needs a lot of steeling under any circumstances. 15* will give you good "absolute" sharpness without changing the knife's maintenance needs by much. It's amazing -- at least to me -- that carbon Sabs take and hold a more acute edge than nominally "stronger" and harde knives like Wusthofs.

Don't bother "thinning behind the edge." That sort of multi-beveling won't make a positive difference but will weaken the edge and make it more likely to ding out of true.

On the other hand, you might want to try a slightly more obtuse micro-bevel; but because Sab carbon edges are so long wearing, that's probably a waste of time, too. But it's a waste of less time, so feel free to try it.

K-Sab's factory sharpening is very inconsistent. I wouldn't bother trying too hard to repeat it. The nominal factory edge angle is probably somewhere between 20* and 22.5*. I think it's too obtuse for the knife.

If you're going to use the EP to profile a knife to a more acute angle, use the "Magic Marker Trick" to make sure you're sharpening all the way down to the edge. 

Ink the knife;
Using your coarsest stone, grind down to the edge on one side, taking your time, using very light pressure, and not worrying whether you're pulling a burr;
Turn the knife over, and do the same thing on the other side; then
Compare the two bevels to make sure they are of roughly even width and the bevel shoulders are parallel to the edge for the length of the knife;
Re-ink the knife;
Do whatever "sectioning" or "touching up" is necessary to get the bevel shoulders and symmetry exactly right -- still not worrying about a burr, and using as little pressure as possible; finally
Swap out the coarse stone for a medium, and sharpen as usual.
As always with the EP: 

Take your time; and
Use as little pressure as possible.
BDL


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## betowess (Feb 14, 2013)

Thank-you BDL for taking the time to give me such a detailed play by play on using my EP!

Now you've got me thinking I need to find my old loupe (to compare the bevel edges), if I still have it from film days. If not, I suppose I can pull out an old 50mm Nikon or Canon lens and flip it over; they make great loupes and my eyes don't focus like they use to!

I think I might go for an 18* angle, that seems like a fair compromise for durability vs. ease of use. Thanks again. This is very useful information for starting out!


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## boar_d_laze (Feb 13, 2008)

It's in the nature of how most freehand sharpeners find the angle, i.e. by "clicking in," for freehand sharpening to result in an increasingly obtuse edge bevel with each successive sharpening. Consequently, it's a good idea to re-profile the knife -- that is, thin it -- every third or fourth sharpening. As in a lot of sharpening choices there's a balance between waiting too long and thinning too often. In this case, the tension is between losing some _perceived_ sharpness and using up the knife by moving the amount of metal necessary to effectively thin.

I never thin my carbon Sabs "_behind _the edge." I have a lot of knives, and many of them work as well with simple "V" geometry as they do with more complicated shapes. All of my carbon Sabatiers are sharpened to a flat, 15* edge bevel with roughly 60/40 right handed (to benefit my wife, Linda) symmetry. I used to use a more complex 20*/15* geometry, but it turned out not to work better than the flat 15*. So, wotthehell wotthehell.

But not all knives are carbon Sabs. Some knives are better with complex bevels, MAC Pro by way of an example. Because I can get 95% of the benefit out of a "micro-bevel" than I can out of a more complex shape, like a true "multi bevel" or a convex edge, AND because I can lay it in easily freehand, I tend to work with and recommend micro-bevels more than true, complex bevels.

If you sharpen with a tool and jig which sets effective and accurate angles, I'm not sure how long you'd go before re-profiling was necessary. In theory it could be forever. However, I don't use my EP that consistently, and couldn't tell you for sure. If I remember correctly, Phaedrus knows the EP really well, so you could PM him. If he doesn't know, call or shot an email to Ben (Dale) at Edge Pro and ask him.

Time for a linguistics break. I'm dancing around using the term "double bevel" as it relates to the simplest of the multi-bevels because the term is often applied to distinguish between edges which are only sharpened on one side and edges which are sharpened on both and has become ambiguous. The use of the terms "secondary" and "primary" as they relate to which bevel is the more acute angle which transitions from face to edge and the more obtuse angle which does the actual cutting is also ambiguous. Old timers like me, usually use "primary bevel" to mean the one that does the cutting... but if you run into someone who uses the terms make sure to ask what the hell he means before assuming you know.

At any rate, two bevel angles per bevel is the usual multi-bevel. It's pretty easy to create a double bevel with similar angles using an Edge Pro (or similar) but almost impossible to do it by hand. The best work around is to do something called a micro-bevel. That is, profile and sharpen the knife in your usual way at an acute angle, going all the way through your grit progression. Once the knife is sharp, polished and deburred, sharpen it again on your final stone at a slightly more obtuse angle, using only very light pressure and a very few strokes. The idea is to lay in that final edge angle without drawing a new burr.

To get a true double bevel using a tool and jig... profile and sharpen the knife to the more acute angle going through all the "necessary" grit levels, except for the final polishing stone -- whatever that is. Then re-sharpen the knife going through all the levels, including the final polishing stone, at the more obtuse angle. If you're not extremely good at seeing what's going on, use the frikkin' Magic Marker Trick to make sure you don't cut too deeply into the more acute bevel.

If you want a triple bevel (on each side) use a Chef's Choice "Trizor" machine. FWIW, it's not the sharpest possible edge, isn't particularly well polished, but is -- by God -- durable.

For the vast majority of sharpeners, laying in a convex edge on a kitchen knife without a belt sander is doable, but... I'm not a big fan of convex edges for kitchen knives, you can get them sharp (if you know how), and they're very long lasting, but are too hard to maintain. FWIW, you're going to get a fair amount of convexing and a good deal of the benefit anyway as a normal artifact of freehand sharpening. Some people really love them, but I think it's a waste of time to sharpen and maintain them by hand (as with "the mouse pad" trick).

BDL


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## betowess (Feb 14, 2013)

This is fascinating - reading about the art and science of cooking knife bevels. I have read each of BDL's post a couple of times to absorb it all.

I practiced on a quite dull new Ebay "Old Hickory" last night with the EP.  It was their 8"slicer, which is fairly thin blade, and a pain on its tip where it was so thick and blunt ended. I finally ended up putting it on a diamond block to profile that tip, because it was so thick. That made me appreciate the factory grind of the Sabatiers.

I'm going to continue practicing a bit more with the EP on the old hickory, and a Knives of Alaska D2 steel hunting knife and a few others, before I launch into my Sabs. The Sabs are still pretty sharp, from a previous sharpening when I first got them., but I might try that 15* angle you have recommended. Thanks for the wealth of info here BDL. I think you should consider publishing a book on knife sharpening.


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## betowess (Feb 14, 2013)

boar_d_laze said:


> All of my carbon Sabatiers are sharpened to a flat, 15* edge bevel with roughly 60/40 right handed (to benefit my wife, Linda) symmetry. I used to use a more complex 20*/15* geometry, but it turned out not to work better than the flat 15*. So, wotthehell wotthehell.


One quick question BDL. When you say you sharpen at a flat 15* but with a 60/40 right hand asymmetrical, aren't those two slightly different angles? I'm guessing they are, but I'm a newb at this stuff so I'm trying to figure it out... Thanks again...


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## boar_d_laze (Feb 13, 2008)

Betowess,

This question gets asked a lot:


> _When you say you sharpen at a flat 15* but with a 60/40 right hand asymmetrical, aren't those two slightly different angles? I'm guessing they are, but I'm a newb at this stuff so I'm trying to figure it out... _


The answer is: No, my angles are the same on both sides. It's possible to sharpen different angles on the opposite sides of an edge but without using some sort of angle holding jig it's very difficult to do. Worse, it's largely a waste of time.

So, what is asymmetry? Why do it? How do you sharpen it?

As a practical matter asymmetry means moving the apex of the edge so that it's not directly below the center of the spine. If it's moved to the right side of the knife (right, looking down from the spine) the knife will be "left-handed," and if it's moved to the left, the knife will be "right-handed." To create right-handed asymmetry, the bevel is made wider on the right side than on the left side, and -- of course -- vice-versa for a left handed knife. Confused yet? If you are, take a minute and try to visualize.

As an inevitable product of their geometry, an asymmetric edge is thinner at every given point from the edge to the bevel than a perfectly symmetric (50/50) edge; until that is, the edge ends at the wider bevel, and the knife's width is solely a product of the face grind angles.

A narrower edge has less tendency to "wedge," than a wider one -- where wedging is the tendency of the knife to push things sidewise and tear them as opposed to cutting them, and consequently is perceived as sharper than a wider edge, even if the edges are otherwise sharpened and polished in exactly the same way. That's the good part. On the other hand, the more asymmetric the edge, the greater the tendency to deform with impact (rolling, waving, collapsing, etc); this is even worse than you might thing because highly asymmetric edges are extremely difficult to true using a steel -- which is the quickest and most convenient tool for truing.

The "best" combination of bevel angle and asymmetry is going to be the most acute angle and highest degree of asymmetry the knife can take without requiring too much maintenance. How much is too much? Only the user can say.

The way to create an asymmetric edge is simply to sharpen one side more than the other. The degree of asymmetry is expressed as a ratio of the bevels' comparative widths. The most common way to express the ratio is as a matter of percentage. That is, 50/50 and 60/40 are ways of talking about the simple numerical expressions 1:1 and 3:2 as percentages. Neither way tells you more than the other.

The degree of asymmetry is _nearly_ always judged by eye -- as opposed to a more accurate measuring device. Given the vagaries of sharpening, that means that the degree of asymmetry is almost always fairly inexact. In other words, precise ratios are more aspirational than facts and the number is more a range rather than a precise reality. 60/40 and 70/30 both look very much like the 2:1 to the human eyeball. Consequently, you're as likely to get one as the other no matter how careful you are.

Sharpening always represents something of a tension between sharpness and durability. The more asymmetry, the higher the degree of perceived sharpness but the less durable the edge. I like to keep something of a balance, and consequently I tend to sharpen "V" edged knives at 2:1. But when I write about it, I usually say 60/40, because that's more common.

The surprise moral of the story is not that you should sharpen at 2:1 also, but that you would watch out for people who make a big deal of the difference between 60/40 and 70/30 because they usually either don't know what they're talking about or are trying to bull$h!t you. Ditto with people who make an issue out of the differences between very similar angles.

Hope this helps,

BDL


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## betowess (Feb 14, 2013)

OK, much gracias BDL! I imagine you could tire of endlessly explaining asymmetrical knife angle geometry to newbs, but I believe I follow now, *I think*.

After reading your post a couple times I then stumbled upon a Mark Richmond video explaining similar details, because I had one question which formed because I was thinking too hard about it (as usual)... which I believe the video answered - and on re-reading your post again, you also answered quite well.

And that question was: from which point you are looking down the spine, say on a right handed knife, from the point - or from the handle? And the correct answer would be from the handle/choil - and that bevel on that right side is indeed a bit larger/longer than the one on the left side, correct?

Anyhow, you get there by grinding fewer strokes on the left side (assuming the grind pressure and angle is roughly equal) and more strokes on the right side, on a right handed knife.

For example, using a 60/40 asymmetrical right handed knife, you might grind 6 strokes on the knife's right side vs. 4 strokes on the left. At least this is what I get from your detailed explanation and watching Mark's video on utube...

Anyhow, after drawing lots of triangles on paper and looking and over thinking about it, I get it now (I hope) and can only thank-you for taking the time to get me to cognition.

_Little plum angle fairies dancing through my head!_ thanks


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## ron arazi (Jun 8, 2012)

There is a great shop in new york called Korin and they have some knife sharpening

"classes" you can find on you tube, like this-






very proffesional with a lot of good info.

cheers

ron


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## betowess (Feb 14, 2013)

Thanks for the link Ron! I found the 3rd episode on petty knives, very informative.


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## boar_d_laze (Feb 13, 2008)

_Videos and Other Sharpening Learning Aids: _

Regarding the Korin sharpening videos...

I strongly recommend against the "coin trick" for angle finding in particular and don't think the Korin series is really all that good.

Instead look at a couple of other free, sharpening series which are MUCH better, the CKtG and JKI series. They're (respectively) on the Chef Knives to Go and Japanese Knife Imports sites (Shocking, isn't it?). They're both very solid learning aids for beginners, both both far more informative than the Korin videos, and both are technically more solid. For what it's worth, Jon at JKI is one of the best sharpeners in the country. As it happens, I like both series about equally; that either is enough to take almost anyone from virginity to basic sharpening competence; that neither will leave you with bad habits; and that you might as well watch both.

I also suggest reading the eGullet FAQ by Chad Ward in its entirety, The sharpening chapter in Chad Ward's book, An Edge in the Kitchen, is better written and more complete than his FAQ. And if you're really into this stuff you might want to dig up some of John Verhoeven's online articles, especially Experiments in Sharpening. My own journey began with John Jurantich's magazine articles, and his _Razor's Edge Book of Sharpening_, is worth reading even though a bit dated. Steve Bottorff has a lot of good information, and you might want to take a look at Chapter 3 of his online pamphlet. That said, I think a lot of Juranitch's and Bottorff's equipment recommendations aren't very good, and specifically recommend that you stay away from edge guide clamps and the Lansky (rod guide) sharpener.

Otherwise, there are a lot of sharpening videos on YouTube which are just plain wrong and it's probably best to avoid them until you're a good enough sharpener to understand why they're more about _Stupid Human Tricks _than effective sharpening, and enjoy a sadistic laugh at their unintentional humor. You get enough of that here, anyway.

_Freehand Sharpening Asymmetry and Plugging The Burr Method:_

First, I don't count strokes. Ever. I sharpen and teach sharpening according to _the burr method_ (pretty much as Chad Ward describes it), which depends on tactile and visual tests to measure progress. If you choose to sharpen using the burr method, as an aid to visual evaluation you should always use _The Magic Marker Trick -- _at least until you know what you're doing and can see subtle changes without it.

As a way of speeding up the process and saving some metal, I start sharpening on asymmetric blade on whichever side is going to get the wider bevel. On a knife I wanted 60/40 right handed, I'd start sharpening the right side's bevel until I drew a burr, flip the knife and chase the burr to the other side -- because it takes more metal to draw the burr then it does to chase it -- before chasing and refining the burr in the regular way. I touch and look at the knife frequently to check on my own progress.

A consequence of the "it takes more metal to draw a burr" phenomenon is that if -- as a matter of habit -- you always start sharpening on the same side, you'll develop an asymmetry unless you take steps to prevent it. If and when you notice symmetry-creep, section the knife by giving the side which needs some extra work some extra work. Usually it's enough to just start on that side.

Whether you count strokes or not, whether or not you consciously pull a burr, whether or not you deburr by pulling the edge through something grabby; etc., pulling a burr and deburring are necessary of creating a fine, fresh metal edge. It's my experience that the best way for the type of person who learns best by understanding what's going on as a part of mastering a skill is to approach sharpening via _the burr method_.

_Final Caveat and Disclaimer:_

_The Burr Method _is *NOT* the only right way to freehand sharpen. There are plenty of excellent sharpeners who take different approaches, including counting strokes.

BDL


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## betowess (Feb 14, 2013)

Thanks BDL. I have been working through some of Mark Richmond's Cktg demos, though I can't try freehand - I haven't bought any water stones yet.

That Chad Ward link is terrific, full of information. I have watched a few of Jon Broida's great videos and will watch more of them later.

I especially enjoyed reading through the Zknife listing of all the different Japanese knifes. As you know, it is a very long list and fascinating... here is a link if anyone wants to check it out. http://zknives.com/knives/kitchen/misc/usetype/all/index.shtml

Thanks again BDL.


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