Knife sharpeners

[dmt123]

[I use the diamond technology to sharpen knives,tools & gardening tools....what type of sharpening tools do you use? Please let me know.....[/indent]

[Dirk Skene]

DMT I do not use the bench mount for my kitchen knives. I lay the "stone" on the mat & use the angle guide. Since I sharpen them regularly now, I use only the fine/extra fine.

[boar_d_laze]

Steve (or is it Stan?),

This is raw spam, and you ought to know better. Still, it's always a good idea to get a discussion on sharpening going among people who cook.

I use four 8" x 2" x 1" stones for all my sharpening. A 6" stone is too small for kitchen knife sets which include blades 8" or longer -- in other words, most of them.

My coarsest is a coarse India (India stones are Norton's name for aluminum oxide). The stone is used for repairing old knives and re-profiling knives as needed.

The next finest is a fine India. The stone is used for beginning the sharpening process. Like all good sharpeners I do this by raising a wire (aka a burr or a bead), first on one side then the other. Then refining the wire to make sure the knife is evenly profiled and sharpened across the entire length of the edge. I do this by touch.

(The sharpening technique you show on your website -- counting strokes rather than testing the edge -- is problematic even on stones as aggressive as yours.)

A Hall's Soft Arkansas comes next. At first I use it in exactly the same way as the fine India. But once the wire is refined, I change from circular grinding motions to alternately cut-stroking each side, and use the soft Arkansas to sharpen off the wire. The jump in grits from fine India to soft Arkansas may not seem very high, but the fine India raises the wire much faster, and the soft Arkansas leaves the perfect butchers edge.

My final stone is a Hall's Surgical Black Arkansas. When it comes to kitchen knives, I save this for knives used primarily for chopping (what knife geeks call "push cutting").

For the quantification oriented: The coarse India is roughly equivalent to a 200 grit stone; the fine to an 800; the soft Arkansas to a 1200; and the black to a 5000. In fact, stone "grit" is not a very consistent guide to speed or polish, so the numbers and equivalences are, as I said, rough. In DMT terms the find India is very much like your Fine, and the soft Arkansas a lot like your XFine -- although the DMT stones sharpen MUCH faster.

I use my stones without oil, water, or any liquid; and clean them in the dishwasher. The change to dry sharpening and dishwasher cleaning has made an enormous difference in the speed and performance of my stones.

In addition to the stones, I have two steels. One is a HandAmerican borosilicate, and the other a Henckels fine-groove I've had for thirty years or so. Without getting too deeply into the distinctions between these, let me say that I think it's a good idea for a home cook to develop the habit of steeling every time the knife comes out of the block to straighten edges that have begun to curl from impact on the board; and a good idea to steel after sharpening on intermediate stones as a smoothing and polishing final step.

My sharpening tools are appropriate for me and for my knives. My technique is not only too complicated and time consuming for lots of people, it involves developing a skill. Admittedly, not a very difficult skill, but still intimidating to some. Nearly all of my knives sharpen easily and hold an edge well, so India and Arkansas is fast enough.

Even the finest DMT stone surface is too coarse too polish, and the most refined DMT edge is about mid-level meat cutting -- less polished than ideal for a chef's knife, even after smoothing on a good steel. So, great as part of a set but not as a complete solution. In my opinion, your steels are way too coarse for the edge smoothing and straightening tasks they do best. Still, they are the best of their type.

DMT are the best diamond stones you can get. I like them for speed and flatness. In a "cost is no object" set, or in a set for a knife collection including blades made of very tough steel, I'd probably use an 8" DMT Coarse-Fine combination for my coarsest stone, and as a flattener; and add some ceramic Shapton Glasstones for final sharpening and polishing. Fair warning, a set of stones like this, plus a good steel, would run well over $300.

BDL

[Yankchef]

DMT are the best diamond stones you can get. I like them for speed and flatness. In a "cost is no object" set, or in a set for a knife collection including blades made of very tough steel, I'd probably use an 8" DMT Coarse-Fine combination for my coarsest stone, and as a flattener; and add some ceramic Shapton Glasstones for final sharpening and polishing. Fair warning, a set of stones like this, plus a good steel, would run well over $300.

BDL[/quote]

That last bit describes the set of sharpening stones that I currently have and yea if you add it all up it gets expensive. However the DMT stones are excellent as flatteners, way better than any flattening stone I have encountered. Think creme brulee, how many creme brulee torches have you seen that perform really well? Nope the best ones usually come from the hardware store and dont say creme brulee on them... if that makes sense.

Well over 300 dollars I think might be a little big excessive, although they have jacked up the price on the HA borosilicate steel from 55 to 70 dollars. My set for sharpening includes the following and with prices as well to give you an idea of what you might be getting into.

DMT D8C 320 grit $35
Shapton Glassstone 1k grit $42
Aoto Natural Mountain Stone 2-3k grit $65
Stone Holder $12-15
HA Borosilicate steel (Tks BDL it kicks ***) $70
Idahone Fine Ceramic Steel 12 inch $27

All of those prices are without shipping charges so I would say tack on another 20-30 bucks depending on how many different sites you buy everything from or if there is a store near you that you can purchase.

This set is awesome, I don't find highly polished edges necessary and I use the aoto as my finishing stone with excellent results. I am also sharpening all gyutos, santokus and paring knives so I am not talking about slicers. If you want a basic starter set you can get just the DMT and shapton makes a great kit for home cooks and even most pro cooks. Also norton makes a good combi 1k/4k grit stone that isnt too expensive and King makes a 1k/6k that you can get for about 30 bucks and see if water stones are for you. I find then to be the best way to sharpen knives, specifically hard Japanese knives and the fastest way to sharpen european knives as well. However you must keep them flat so even if you buy one all purpose stone you are buying 2 for just that reason. You don't have to spend over 300 bucks to get a nice set... but nice things cost money

O what are you trying to sharpen by the way that would be good to know...

[adamm]

Right now i use a 325, then a 1200 dmt. I finish with 6000 grit water stone and leather stops. Im upgrading to Glastones. I like the diamond stones but they dont seem to cut as good as when i first got them.

[MaryB]

I use the Apex Edge Pro. Keeps the sharpening angle pretty constant except at the tip. Edge Pro, Inc. puts on a very good edge.

[MikeLM]

I just got a ChefsChoice 110 sharpener, since I'm too lazy to do a good job by hand, and practiced on several old knives. I had a Forschner boning and two old Henckels, all stainless. I couldn't raise a burr on any of them, but they worked out to a pretty good edge.

I took an old Sabatier 12" Chef's with a cast-on bolster which is - quite obviously - not stainless. I raised a strong burr on each pass through the pre-sharpening wheels, and then worked it out to such an edge I'm damm near afraid to pick the thing up. Don't know yet how long it will last. Certainly a difference in the metals.

I guess I'll just touch it with my diamond steel whenever I use it, to see how it goes, although the instricutions with the sharpener say not to do that.

Later, I'll try it on my good stuff. (No Japanese or ceramic.)

Mike

[boar_d_laze]

Originally Posted by MikeLM

I just got a ChefsChoice 110 sharpener, since I'm too lazy to do a good job by hand, and practiced on several old knives.

Chef's Choice electrics are excellent sharpeners for people who won't or can't hand sharpen -- maybe the best choice for most people who can afford one. Your particular model is a little tricky, in that the knife can wander a little in the holder as you draw it through. Pay attention always and you'll be alright. Look away and you'll cut a scallop into your knife.

I had a Forschner boning and two old Henckels, all stainless. I couldn't raise a burr on any of them, but they worked out to a pretty good edge.

The Forschner -- if it's from the Rosewood or Fibrox series -- should come up with a wire pretty easily. Henckels stainless is particularly tough because of the ice-hardening. It's possible the wire is being ground off as soon as it's ground in. Try multiple passes on each side, continue checking for a wire before moving on to the other side. If you don't get a wire after 15 or 20 passes, even out the profile and move on.

I took an old Sabatier 12" Chef's with a cast-on bolster which is - quite obviously - not stainless. I raised a strong burr on each pass through the pre-sharpening wheels, and then worked it out to such an edge I'm damm near afraid to pick the thing up. [...] Don't know yet how long it will last.

The "trizor" edge will last a long time. It's a triple bevel and not even the primary bevel is very acute. The Chef's Choice edge is a good one. But it is not nearly as good as the edge a skilled hand sharpener using appropriate stones can put on your knives.

Tangentially, I've never heard the term, "cast-on bolster" before. What do you mean?

Certainly a difference in the metals.

Yes, it's a difference you notice even with the diamond abrasives in your machine. If you can tolerate the extra care carbon steel requires (and most people can't) it's better for most purposes.

I guess I'll just touch it with my diamond steel whenever I use it, to see how it goes, although the instricutions [sic] with the sharpener say not to do that.

Trust the instructions, at least as to a diamond steel. You can use a fine groove or smooth between sharpenings if you like, but that diamond steel will do more damage and less good than running the knife through stage 3 for a "touch up."

Later, I'll try it on my good stuff.

What's your good stuff? You may find that the weight and balance make your old carbon steel Sabs the best stuff.

No Japanese or ceramic.

The angles are all wrong for Japanese knives -- way too obtuse. Otherwise, it would be fine. In fact, Chef's Choice makes two sharpeners which sharpen to 15 deg simple bevels. They're excellent. The model M15 is particularly interested. It's not only designed for Japanese knives, but to put a Japanese edge profile on Western knives made from good enough steel to handle it. Many Japanese knife owners would be best served with a Chef's Choice yet avoid them for the wrong reasons. Similarly, many high-end Euro owners could benefit by profiling their knives to more acute angles.

Ceramic is its own world. Let's not go there.

BDL

[Yankchef]

Hate to be that guy but something should be said of what these high octane diamond sharpening machines can do to a blade... I don't know what kind of longevity they offer in terms of edge retention but I do know from having a diamond stone myself that diamonds are very abrasive and remove a lot of material. Chefs with 200 dollar plus knives wouldn't let their knives within 10 yards of such a device and the crazy amount of material it removes. If you have cheap knives and want a quick and painless way of making them sharp fine but for my high end knives i will stick with hand sharpening with wet stones.

[dscheidt]

Originally Posted by boar_d_laze

.

The next finest is a fine India. The stone is used for beginning the sharpening process. Like all good sharpeners I do this by raising a wire (aka a burr or a bead), first on one side then the other. T

BDL

I'm going to call you on the "all good sharpeners raise a burr". To get an edge maximally sharp for a given included bevel angle, it's necessary to have the two bevels meet at a point that is the edge. If you've raised a burr, you've gone past that point, and correct for it by sharpening the other bevel. There's not much wrong with that; it means you remove a bit more metal from the edge than is absolutely required, and it means that the bevel at the edge gets a bit more obtuse faster, and so requires sharpening the primary bevel a bit more often. It's easy to get it right, which for the vast majority of people outweighs the disadvantages.

It is perfectly possible to get the bevels to meet properly without raising a burr, by visual inspection. That requires bright light, and some level of magnification. The only people who do this are the sort of people who like to whittle hair.

[boar_d_laze]

Originally Posted by dscheidt

I'm going to call you on the "all good sharpeners raise a burr". To get an edge maximally sharp for a given included bevel angle, it's necessary to have the two bevels meet at a point that is the edge. If you've raised a burr, you've gone past that point, and correct for it by sharpening the other bevel. There's not much wrong with that; it means you remove a bit more metal from the edge than is absolutely required, and it means that the bevel at the edge gets a bit more obtuse faster, and so requires sharpening the primary bevel a bit more often. It's easy to get it right, which for the vast majority of people outweighs the disadvantages.

It is perfectly possible to get the bevels to meet properly without raising a burr, by visual inspection. That requires bright light, and some level of magnification. The only people who do this are the sort of people who like to whittle hair.

Okay. Your point is well taken. Change that to: "Like '99 and 44/100%' of all good sharpeners..."

I agree with "possible to get the bevels to meet properly" but what is possible is not practical. There are a number of reasons why I believe this to be so.

No actual edge is perfect along its length. Every edge has some width. The narrower and more consistent the width is, the better the edge. "Sharp" is usually defined as somewhere under .003" along the length of the edge. "Very sharp" is probably around .001".

Edges are usually created and restored with a regimen of decreasing sizes of abrasive (grinding, sharpening, polishing) requiring many iterations of contact. The contact, if done by hand, is usually performed with two or three distinctly different types of motions (grinding, sharpening, stropping), at two or more different pressures (firm with pressure from the off hand, firm, light, etc.). Consequently, few hand sharpeners can sharpen every part of the blade evenly. Even using aids like rod-guides, it's nearly impossible to bring every part of the edge to "sharp," i.e., "to meet properly" as you put it, without going beyond "proper" in at least a few places along the edge -- and bringing up a wire.

It is highly impractical to stop after every iteration to inspect the blade under magnification. It is much simpler to go a little beyond "ideal," because a wire is easily detected by feel, and sharpening the wire off is a useful way to approach the practical limits of sharpness. While microscopy and micro-metrics are useful in learning about efficient sharpening, they are not efficient for usual practice. They take too long.

Your description of how a wire is raised, i.e., "going past that point" is established dogma. But, is it true? Let me stress that what you're saying is absolutely right in the sense that it agrees with nearly all of the knife people who have written on the subject from a sharpener's perspective. But [ahem] my understanding of the math, physics and metallurgical aspects, leads me to believe that a wire inevitably forms when using stones for sharpening all but the toughest and thickest blades as the edge of either bevel approaches the ideal sharp point. This is as much a consequence of the bevel face lengthening as the top of the bevel moves up the blade as the bevel face is "sharpened" as of anything else. That's because the "equal and opposite force" on the opposing blade face is concentrated over a smaller area, and this results in bending. Admittedly this is not the common view, take it for what it's worth.

The "glint" method of evaluating an edge is primarily useful (to me anyway) for illuminating (hah!) regions along an edge which are disproportionately dull or waved compared to the rest of the edge. It works well for highlighting (did it again!) areas which need more work, but is of lesser utility than many other tests for determining ultimate sharpness. To name just a few: Razor Edge Systems' (Jim Juranitch) Sharpness Tester; various paper tests, (Murray) Carter three finger test; thumb nail test; back of the hand shaving; thumb drag; and using the blade for the purpose for which it is intended.

I'm sufficiently sanguine about my knife sharpening skills -- which include raising a wire -- that dragging my well educated thumb usually tells me all I care to know on the way to using the blade, which in turn tells me all I need to know at all. Shaving, "popping," and carving hairs doesn't convey much real information -- especially for culinary knives. That doesn't mean that my arms and the backs of my hands aren't patchy with bald spots. It ought to be abundantly clear that I like farting around with this stuff enough to play with most of the other tests occasionally. Not to mention new and/or other peoples') equipment. If a good test really matters to you, I recommend the Razor Edge Systems Sharpness Tester, it's certainly cheap enough.
Testers - Razor Edge Systems

I'm okay, but by no the world's best sharpener. No one mistakes me for Chad or Jim or Murray or Lee (I know you like him) or Dave or ... well, a gazillion other people. If one thing should be clear about my skill level, it is that I'm a student and not a master. Although I'm using very old technology (India stones, Arkansas Stones, carbon steel) my technique continues to change and evolve -- sometimes as a result of new information, and sometimes because my native complacent stubbornness is sufficiently overcome for me to act on something that's been obvious to anyone with a brain for a long time. As you know, I recently started using an adaptation of Juranitch's dry method (published in the fifties) combined with using a dishwasher (thirties tech) to maintain my stones (nineteenth and early twentieth century).

Some skulls are thicker than others,
BDL

[MikeLM]

BDL-

"I've never heard the term, "cast-on bolster" before. What do you mean?"

Just that. It's evidently a stamped blade (anyway, it's all flat) with a full tang, and a bolster in front of the handle (!) that is clearly quite different metal from the blade material.

Looks a lot like zamak but a little less grainy. I've seen several references to these, but the Sabatier is the only one I've seen. Got it so long ago I've forgotten where. Handle still in good shape.

The Forchner boning looks to be the Rosewood; I've never worked with that wood, but I think the handle probably is. It's also pretty old, and faded. I'll oil it and see what I get.

I enjoy kicking this kind of stuff around.

Mike

[boar_d_laze]

Originally Posted by MikeLM

BDL-

"I've never heard the term, "cast-on bolster" before. What do you mean?"

Just that. It's evidently a stamped blade (anyway, it's all flat) with a full tang, and a bolster in front of the handle (!) that is clearly quite different metal from the blade material.

While not totally sure about this, I don't believe any of the companies making Sabatier stamped carbon blades. I'm fairly sure all of the carbon was forged. Most of them were either true martinet forged or forged by very heavy hammers. In either case, they are forged into shape using a mold, and the bolster is an artifact of metal moved off the blade during the forging process.

Is it possible you're confusing the ferrule for the bolster?

Looks a lot like zamak but a little less grainy. I've seen several references to these, but the Sabatier is the only one I've seen.

I'd love to see those references. I (sort of) collect carbon steel Sabs.

Got it so long ago I've forgotten where. Handle still in good shape.

What kind of handle? POM with a full tang or ebony with a rat tail? Any identifying marks on the handle or blade? Stars? An oval with the Sabatier name? Anything like that?

The Forchner boning looks to be the Rosewood; I've never worked with that wood, but I think the handle probably is. It's also pretty old, and faded. I'll oil it and see what I get.

If the handle's wood, there's no ferrule or bolster, it's a "Forschner Rosewood." They made boning knives with straight and offset handles, in several flexes. For the handle, use plain mineral oil from the drug store, according to the following schedule: 1st day, 2d day, 4th day, 7th day, 14th day, 30th day, 60th day, and 90th day. After that the wood will be as restored as it's going to get, and you can oil it whenever you sharpen it.

I enjoy kicking this kind of stuff around.

Yeah. Me too.

Thanks,
BDL

[MikeLM]

BDL-
I've been tied up and slow to respond. I'll get to it, including a couple pix, as soon as I can.

Mike

[DMT]

Dang, I may need to inquire about a user name change...

I am in no way associated with the products advertised in the opening post...