How sharp is "sharp"?

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Curious, Alan, how you are holding your knife? That could be affecting your perception of sharpness.

Not sure what you mean...I hold it with my right hand and put my index finger over the top of the blade.
 
That is true. However, inattention or improper cutting technique will land you in trouble with a sharp blade. Redeeming factors are that the cutting won't hurt much if you feel it at all because it will be cleaner and the cut will heal both faster and with less scarring.

I don't know, with that tomatoe demo, I don't even want to think what a knife like that would do to a finger with even the lightest force.

My Wustoff is far from dull, but I'd have to put a fair bit of force and just completely straight on chop into my hand to do serious damage (which is unlikely with proper chopping technique).

With that Japanese knife, I think even a graze could be devastating, like cutting through butter with a hot knife :ohmy:
 
I keep my Chroma 10" Chef's knife super sharp so that it cuts effortlessly. A sharp knife will indeed let you know when you are stupid. Fortunately, I have strong thubnails and they have saved the corner of my thumb a few times.:LOL: Learn to use the knife properly and you won't get hurt. Chopping, slicing, necomes effortless and faster. Food quality goes up as well. Just keep finger and thumb tips out of the way. And if you are one of the truly accident prone (I'm not saying you are), then you can purchase finger and knuckle gaurds just to protect the parts you are most likely to injure.

Seeeeeeya; Goodweed of the North
 
A sharp knife will let you think you've had a near miss. I've had times when I've cut myself and it's taken over 30 seconds for the bleeding to start.
 
Not sure what you mean...I hold it with my right hand and put my index finger over the top of the blade.

Here is a good site to learn everything you ever wanted to know about knife sharpening: Sharpening Made Easy

Even an inexpensive knife can have a reasonable lifespan between sharpenings with proper use of a steel. A good cutting surface is also important. Wood is still the best surface for edge preservation (end grain in particular), with plastic next (plastics vary... softer is usually better). Glass or stone cutting boards should never be used with a good knife.
 
Here is a good site to learn everything you ever wanted to know about knife sharpening: Sharpening Made Easy

I've previously read all of Bottorf's stuff before. While the information is good, remember that it is one man's opinion. If you're tempted to try his paper wheels, be careful and practice with some beaters. It's all too easy to overheat the edge and ruin the temper.

Even an inexpensive knife can have a reasonable lifespan between sharpenings with proper use of a steel.

I use a steel that came with a block set 30 years ago to poke holes for planting seeds in the garden. Don't use them for knives if you can avoid it. Use a fine ceramic steel like the Idahone or a HandAmerican Borosilicate steel. I steel "steel" will rip up the edge as can easlily be seen with a loupe. Not good, and diefinitely not sharp. :glare:

A good cutting surface is also important. Wood is still the best surface for edge preservation (end grain in particular), with plastic next (plastics vary... softer is usually better). Glass or stone cutting boards should never be used with a good knife.

A Sani-Tuff rubber board is every bit as easy on knives as end grain wood. They're kind of ugly but there's a reason they're found in many commercial kitchens. Poly boards have a place in my home, but only for proteins, and I am very careful to have minimum edge/poly contact. The sharper the knife, the more problems with poly.
 
I've previously read all of Bottorf's stuff before. While the information is good, remember that it is one man's opinion. If you're tempted to try his paper wheels, be careful and practice with some beaters. It's all too easy to overheat the edge and ruin the temper.



I use a steel that came with a block set 30 years ago to poke holes for planting seeds in the garden. Don't use them for knives if you can avoid it. Use a fine ceramic steel like the Idahone or a HandAmerican Borosilicate steel. I steel "steel" will rip up the edge as can easlily be seen with a loupe. Not good, and diefinitely not sharp. :glare:


A Sani-Tuff rubber board is every bit as easy on knives as end grain wood. They're kind of ugly but there's a reason they're found in many commercial kitchens. Poly boards have a place in my home, but only for proteins, and I am very careful to have minimum edge/poly contact. The sharper the knife, the more problems with poly.

You're saying that using a "steel" steel is wrong???? Gee, it seems to have worked for me for a good many years. It also works for a LOT of professionals, including the instructors at the cooking school classes I attended some years ago. They even have a professional sharpener come in to teach proper knife maintenance, and HE used a standard steel.

So I'm justifiably puzzled by your assertions.
 
Several years ago I stood through a boring demonstration with the promise of a free knife at the end. This free knife is the sharpest and easiest to use knife among all of my expensive cutlery. The only problem is that it is too small, only three inches. I have tried to find another longer one but they don't seem to make them. The box said: Paring Pro, surgical stainless steel. Has anyone ever heard of these?
 
You're saying that using a "steel" steel is wrong???? Gee, it seems to have worked for me for a good many years. It also works for a LOT of professionals, including the instructors at the cooking school classes I attended some years ago. They even have a professional sharpener come in to teach proper knife maintenance, and HE used a standard steel.

So I'm justifiably puzzled by your assertions.

You can see for yourself. Sharpen a knife on stones up to 4k grit, better yet, 8 or 10k if you have one. Look at the edge with a 20x loupe. It's nice and smooth. Now steel it with a 1200 grit ceramic steel and look at it again. Roughed up a little (very very little) but still sharp and serviceable. Now steel it with a steel steel and look again. There are some micro chips and lots of tiny steel hairs.

It had been along time since I've even thought about such simple concepts so I actually took the time to screw up a very nice edge to reprove it to myself. I took a thirty year old Chicago Cutlery slicer with steel comparable to modern day German forged knives. It had been sharpened and polished with a 10 degree secondary bevel and a 15 degree primary bevel and polished to 4k grit. It was sharper than anything you can buy by a long shot. To test the edge I used a combination of visuals with the 20x loupe and the Murray Carter 3 finger test. First I used a 1200 grit Idahone ceramic steel. The result was as always, toothy, and very sharp with almost no changes visually. Then I used a steel steel and the resulting edge was only moderately sharp and contained the steel hairs as described above. The 3 finger test screamed dull dull DULL. I once again used the ceramic steel and the edge came right back to being sharp and toothy with no microchips and no steel hairs.

A steel steel is nothing more than a common hardened tool steel round file!

You tell me that the steel steel makes your knives sharp and that's the way the "experts" teach it at culinary schools. The experts are teaching a way to put an edge on a knife that will cut but just barely. I can tell you with no reservations that you have probably never seen a really sharp knife. If you don't believe me you can do some independent research. There are two dedicated kitchen cutlery knife sites, here and here. Both forums are populated by many Chefs who also happen to be knife guys like me. Please go to them, join up, and ask them if a steel steel will make your knives sharp. Also, don't forget to ask them their opinions on the knife sharpening classes at cooking schools.

Buzz
 
buzzard767, you taught me something today. When I purchaced my Chroma, the directions stated that a steel would ruin my knife. I didn't understand that statement as many years ago, when I purchased a 3-piece set of Chicago Cutlery knives, they came with an accompanying steel. The steel is harder than many that I've seen, and is smooth. Instructions stated that when my knives became dull, I could back steel them, then steel forward again and return the knives to a reasonable sharpness. Now those old knives hold an edge very well, but are hard to sharpen. Back-steeling proved to be a quick way to at least partially restore the edge. I've used the technique for years and my knives go through tomatoes, and virtually everything I cut or slice with ease.

On the other hand, I have two crock-sticks (ceramic rods) that are very smooth. After sharpening with my Smith's Arkansas stone, If I then try to finish them with the crock-stick, they actually seem to be less sharp. But if I very lightly steel them, and I mean barely touching the metal, the edge becomes much more keen.

Still, my knives are not truly razor sharp. They don't shave the hair on my forearm unless I put an extraordinary amount of work into them. Will they slice through paper, like a hot knife through warm butter. But I can't shave with them.

I have heard that finishing a knife edge with a strop that has been rubbed with jeweler's rouge will put a proper convex curve on the edge, making it stronger, less resistant to fold-over, and give the ultimate sharpness. Leather belts suitable for making a strop seem hard to find in my town.

So, I'm still looking for the ideal method to sharpen my blades. My Chroma is plenty sharp to do what I want it to. But I'm kind of a perfectionist, and the knife edge isn't perfect. So I am forced to settle with pretty darned sharp.

Seeeeeya; Goodweed of the North
 
I have an old Crock Stick sharpener, like a Lansky Turnbox. Two ceramic rods, with holes in the wooden base for a primary and secondary bevel. I removed the acrylic handguard and replaced it with a piece of chrome tanned live oak leather, which I can dress with compound. It's fast, and will give a shaving edge. Not a perfect edge, but sharp enough for my needs.
 
when I purchased a 3-piece set of Chicago Cutlery knives, they came with an accompanying steel. The steel is harder than many that I've seen, and is smooth. Instructions stated that when my knives became dull, I could back steel them, then steel forward again and return the knives to a reasonable sharpness. Now those old knives hold an edge very well, but are hard to sharpen. Back-steeling proved to be a quick way to at least partially restore the edge. I've used the technique for years and my knives go through tomatoes, and virtually everything I cut or slice with ease.

I'll be darned. I've never seen a set come with a "smooth" steel. They are very appropriate for soft to medium hard edges. These edges tend to roll with use. That is, the final .5 mm or so will be pushed slightly to the side and the knife will no longer cut as well. The smooth steel rectifies this by gently pushing or pulling the bent portion back into alignment and the cutting ability is regained. This can be accomplished several times between actual sharpening sessions. Eventually the metal becomes fatigued and falls apart in use and you'll know it by its inability to recover. Then its back to the stones.

On the other hand, I have two crock-sticks (ceramic rods) that are very smooth. After sharpening with my Smith's Arkansas stone, If I then try to finish them with the crock-stick, they actually seem to be less sharp. But if I very lightly steel them, and I mean barely touching the metal, the edge becomes much more keen.

The finest ceramic rod is 1200 grit. If you sharpen with a 2k stone followed by the rod you are dulling the edge you just completed. Don't use a rod until you need it as it is not part of the sharpening sequence.

I have heard that finishing a knife edge with a strop that has been rubbed with jeweler's rouge will put a proper convex curve on the edge, making it stronger, less resistant to fold-over, and give the ultimate sharpness. Leather belts suitable for making a strop seem hard to find in my town.

Convexing: This technique makes a very strong edge. The caveat is that compared to a straight bevel, the rounded portion makes the blade fatter near the edge and increases friction thus lessoning cutting ability somewhat. Straight bevel weakness is compensated for by adding a micro bevel which adds strength. It's a little hard to explain without pictures so if you need the references I'll dig them up for you.

Pure straight bevels are only possible using mechanical devices such as the EdgePro. Free handing on stones imparts a convex edge to one degree or another because it is impossible to maintain the exact same angle at all times on the stones.

Strops: Nothing finishes an edge like a strop. The difference is mind boggling and must be seen to be believed.

A simple strop is as easy as gluing a thin, smooth piece of leather onto a 2x4. You can load it with any non greasy or non pumice laden media you want. Your suggestion of jeweler's rouge works. I prefer higher quality control and use only one particular brand of .5 micron liquid and powdered chromium oxide because the particle size is consistent. .5 micron equals about 50k grit so you can see what a high degree of polish it imparts.

When I go all out I finish with a 10k stone, then strop with .5 chromium oxide followed by stropping with .25 diamond spray. This is overkill for sure but extreme sharpening is a hobby of mine so I push the limits on a regular basis.

I've done some experiments using several different types of steels, ie. carbon, stainless, and even semi stainless tool steels. I sharpened them and used 2k as my final stone. I finished with chromium oxide stropping. In every case the increase in cutting ability was beyond description. If you're interested in this I'd be happy to post my sources.

Buzz
 
Well, I guess I just don't feel the need to go to such extremes. I can perform the same test you did with the tomato with my lousy Cutco (don't ask :rolleyes:) chef's knife after my own sharpening, which includes an occasional application of that steel you so dislike. I don't use hard pressure with it, certainly not enough to remove any metal. All it's used for is to realign the burr on the edge.

While what you advocate may be accurate and technically perfect, most home cooks aren't ever going to go through all that just to slice a tomato. It's way over the top and mostly unnecessary. I don't even own any of the sharpening tools that you speak of so casually, yet my knives seem to work well for my needs. For those who want more, it sounds like you have the ticket.

Since all I'm after is a functional knife, and I seem to be able to get that without spending a great deal of time at it, I'm happy with my methods. I'm not, nor will I ever be a professional. I also don't plan to use my knives for shaving... Gillette takes care of that for me. :ROFLMAO:
 
Since all I'm after is a functional knife, and I seem to be able to get that without spending a great deal of time at it, I'm happy with my methods. I'm not, nor will I ever be a professional. I also don't plan to use my knives for shaving... Gillette takes care of that for me. :ROFLMAO:

Each to his own and whatever works for you. I fully realize that I am the exception but that's what works for me. Like I said in the previous post, "This is overkill for sure but extreme sharpening is a hobby of mine so I push the limits on a regular basis."

This is what I do. For anyone who want truly sharp knives, just ask me how.
 
So here's the thing...I have a cheap set of knives that I sharpen several times a week. I'm obsessive about them being sharp, but others have told me I'm being ridiculous and there's no need for a knife to be sharpened that often.

What I would like to know is what is a reasonable sharpness? Is there some kind of test that's recognized to mean a knife is really, really sharp? For me it's the tomatoes and bell peppers that get to me. If I have to apply pressure and really start sawing, I think the knives aren't sharp enough. Unfortunately, I've never gotten to that point with my knives...so I'm wondering if I just have impossible standards or whether my knives are substandard.

You are obsessed but that's not such a bad thing. Try moving your sharpener away from the cutting board, and moving your steel closer. When the knife doesn't perform as well as you like, gently steel it - and see if that helps. You may find that you only need to touch them up with the sharpener once a week or two... and spend more time steeling your cutlery between work.
 
You're saying that using a "steel" steel is wrong???? Gee, it seems to have worked for me for a good many years. It also works for a LOT of professionals, including the instructors at the cooking school classes I attended some years ago. They even have a professional sharpener come in to teach proper knife maintenance, and HE used a standard steel.

So I'm justifiably puzzled by your assertions.

Lots of debate on steeling hows and whats - I use a steel at work, because it is fast, durable and handy. I use a steel steel because a ceramic or glass rod wouldn't last half a day before it got slammed into something, knocked in half, ect... I am also in agreement that the steel will always have a place next to the cook's knife - even when there are better quality options available. If I took 60 seconds to setup and use my SpyderCo during service, the chef would stuff it (and the knife) right where . . . . Suffice to say that a steel is the best and only option for most cooks operating in a busy kitchen.
 
Several years ago I stood through a boring demonstration with the promise of a free knife at the end. This free knife is the sharpest and easiest to use knife among all of my expensive cutlery. The only problem is that it is too small, only three inches. I have tried to find another longer one but they don't seem to make them. The box said: Paring Pro, surgical stainless steel. Has anyone ever heard of these?

I think I was in the same boring presentation, and got the same knife when I lived in Wa. The closest thing you'll find is a Victorinox-style paring or utility knife. You'll be equally or more impressed with those and they're very inexpensive.
 
Lots of debate on steeling hows and whats - I use a steel at work, because it is fast, durable and handy. I use a steel steel because a ceramic or glass rod wouldn't last half a day before it got slammed into something, knocked in half, ect... I am also in agreement that the steel will always have a place next to the cook's knife - even when there are better quality options available. If I took 60 seconds to setup and use my SpyderCo during service, the chef would stuff it (and the knife) right where . . . . Suffice to say that a steel is the best and only option for most cooks operating in a busy kitchen.

Um...yes, and no. I am currently using Japanese gyotus, 210cm Masahiro MSC ms-3000 and 240cm Tojiro DP. Very hard steel, and not to be "steeled." I have an aluminum oxide ceramic stick with a wooden handle I "borrowed" from a Chicago Cutlery steel. It has a square thumb guard, so it can't roll, and I use it like a steel if needed, which is not often. The ceramic only looks delicate...it has been dropped numerous times, with nary a chip. Steeling is for softer blades, and chips harder edges.
 

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