The parts of a knife can be divided into two major parts: the blade and the handle. Each of the common component parts of the blade and the handle are described below.
The blade of a knife is constructed by either forging or cut from stamped steel.
Forged knives are made by heating a bar of steel until softened and dropping the steel into a mold. The steel is then hammered into the correct shape and excess steel is trimmed. The forged blade is then tempered by a sequence of heating and cooling of the steel in order to improve its durability and hardness. The blade is finally sharpened, fitted with a handle, and finished (which may involved polishing to remove any unwanted edges or burrs).
Stamped knives have their blades cut from large flattened sheets of steel. The steel may then be ground down to provide a taper from the spine to the edge as well has from the heel to the tip. Finally, the edge is sharpened, and the blade fitted with a handle. Both forged and stamped blades are made with a protrusion called the tang. The tang is where the handle will be attached through riveting, bonding, or another means.
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Point - The point is the part of the knife at where the edge and the spine meet. The point is generally used for piercing.
Tip - The tip of the knife is usually considered the first third of the cutting edge including the point. This region is usually used for fine work or delicate cuts. The tip is also used as an anchor during mincing.
Edge - The cutting edge of the blade extends from the point to the heel. Virtually all cutting actions of the knife will use this region. Most cutting motions are performed by utilizing a slicing motion (drawing the knife horizontally while pressure is applied downward through force or gravity). In general, the main type of edges are taper ground edge (where the edge is formed by two straight bevels), hollow ground edge (where convex curves are carved out of the edge to form a sharper, thinner, more delicate edge), serrated edge (where the edge is shaped in a series of teeth), scalloped edge (where the edge is shaped in a series of small sharp arcs or bumps), or single edge (where only one side of the knife is beveled - like a chisel's edge). Some knives are labeled granton edge, but typically these knives have a taper ground edge and the blade has shallow divots cut out of it to reduce drag on the knife. These knives are also labeled scalloped, hollow ground, or dimpled by some vendors.
Heel - The heel is the part of the cutting edge farthest away from the point. Usually used when more weight and force are required to cut through (such as hard squashes or thin chicken bones).
Return - The return of the blade is the termination point of the heel. If the return is curved just right, then it allows a gentle rocking motion when preparing to make another stroke or slice with the knife. A well designed return can reduce fatigue and make repeated slicing a smooth cyclical motion instead of a staccato, paper cutter motion. If a finger guard is present on the knife, the return is often unable to be sharpened properly.
Spine - The spine is the top of the knife blade opposite of the cutting edge. A thick spine improves stability of the blade but may also make some cuts feel like you are driving a wedge instead of slicing with an efficient kitchen knife.
Bolster - The bolster is a collar that joins the blade of the knife to the handle. It's function is not to attach the blade to the handle, but to provide additional mass just forward of where the chef's hand is. This improves the stability, balance, and strength of the knife. Some bolsters are constructed with the blade (as in forged knives), while others are attached after the blade is constructed. In the past, it was easy to say that all such bolsters should be avoided because they were of poor quality, however many knife manufacturers have found ways of attaching bolsters to their blades with the same effectiveness as if they were constructed from the same piece of metal. Two notable examples of this are Zwilling J.A. Henckels (who manufacturers their forged blades with different metals for blade, bolster, and tang in a process they call Sintermetal Component Technology) and MAC Knife (who uses stamped steel for their blades). In general, knives which incorporate bolsters in their design are of higher quality than those which do not.
Bolster lip - The bolster lip is where the bolster tapers down to the blade. The lip can be steep, resulting in a sharp angle where the lip meets the blade or the lip can be gently sloped so it blends into the blade. Sharp angles can be a problem when washing the knife because small food particles may lodge in the corner and not be properly washed off. This may result in rusting, metal discoloration, or even bacterial growth if the material persists over time or water is trapped along with it. For this reason, preference should be given to knives with bolster lips that blend into the blade.
Finger guard - Often considered part of the bolster, the finger guard is designed to strengthen the heel of the knife, provide additional weight forward of the handle, and help a little to protect the finger from accidental slipping across the blade. The presence of the finger guard may make use of the heel easier by providing greater mass and stability, but at the same time may make it difficult to use the heel because it is physically larger and does not carry an edge. The use of the finger guard to strengthen the heel of the knife is generally unnecessary with modern steel formulations. A finger guard can be added to a stamped blade.
Tang - The tang is the part of the blade that actually extends into the handle of the knife. The handle is affixed to the blade through the tang. A full tang is a design where the tang is cut to the same size and shape as the handle and handle scales are affixed to both sides. Generally, a full tang is considered to be the most secure method of attaching a handle to a knife and is recommended for knives that will be seeing heavy duty action - like cleavers. Also common are encapsulated tangs which have handles molded onto a tang. Rat tail tangs are also enclosed within the handle and are generally affixed through the use of a bolt or pommel at the handle head. Half tang knives have a tang that only extends about halfway down the handle. These tangs are generally too short for knives that are used constantly or with a decent amount of force. Some half tang knives simply take the tangs and push them into the handle. These knives should be avoided. I recommend knives that have tangs of 3/4 length or full tang as these knifes will last the longest. The long tang gives the handle a better connection to the blade and whole knife will feel a little easier to control because of this connection and the extra weight it will provide to the back of the knife.
Scales - On knifes with riveted handles, the pieces of material (generally a type of wood) which are attached to the tang to form a handle are called the handle scales. The shape and material of the scales determines how the knife handle feels in the hand, if it will be comfortable after a long period or use, and whether or not it becomes slippery when wet or covered in fat. Scales should fit neatly behind the bolster and on both sides of the tang without slits or cracks (to ensure easy cleaning to avoid bacterial growth). The junction where the bolster and tang meet the scales should also be smooth (otherwise, the chef may develop blisters or rub their skin raw during use).
Rivets - Rivets are metal pins used to mechanically join the handle scales to the tang to form the handle. If the rivets are visible, they should be flush to the scales and no cracks should be present along the circle where the rivet meets the scale. Rivets are generally constructed with metal alloys that do not expand or contract much due to heat change to ensure a solid fit throughout the lifetime of the knife.
Handle guard - Many knives have a curvature that the end of the handle that is called a handle guard.
Butt or handle head - Butt is the terminal end of the handle of the knife. Handle head is another name for this part of the knife but is generally used when specifically discussing the handle of the knife.
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What's the professional opinion on those knifes?
The best method I have found for keeping my knives sharp is using a proper ceramic knife sharpener like this: http://www.surfasonline.com/products/21705.cfm
It sharpens the knife perfectly every time and is very easy to use. Certainly a good investment for anyone who wants to look after their knives properly.
Sweet! Which stones do you have?
I ended up getting the Norton stones you recommended: 220, 1000, 4000/8000 plus a flattening stone.
The 8000 puts a beautiful shine on the bevel. I've been practicing on old hand me down knives and bringing each one up to a pretty good level - but none have yet reached the keenness of my Japanese knives. I'm still working on my technique - I'm not perfectly consistent with my angle while drawing the blade across... practice practice practice.
Also, for the person interested in the ceramic knives...think twice before you buy, you them and they BREAK! Both friends who owned them(past tense) chipped and/or scattered them.
Also, for the person interested in the ceramic knives...think twice before you buy, you them and they BREAK! Both friends who owned them(past tense) chipped and/or scattered them.
When buying a santoku for it's rocking motion, be sure to actually try the knife on a cutting board before committing to buying one. Some santokus just don't rock because of the curvature of the final few inches of the blade. If I remember correctly, the Wustof Grand Prix II and Henckels santokus have and abrupt stop while the Global and Wustof Le Corden Bleu santokus have an excellent return for that rocking motion you're looking for. My recommendation? Go to a store like Sur La Table where they have an area set up for you to try the knives on a butcher block. (Most stores will let you hold the knife but not actually slide the knife around on a cutting board to feel how it moves.)
BTW, since this is cooking for engineers, you should do a little research into hardening and tempering steels. :) Knives need both as part of their heat treat, both forged and stamped.
Good description of the function of each part of the knife from a cooking point of view.
As I understand it, the NSF requires stainless steel blades for restaurant use. Since these are also mass-produced by stamping and stock removal, the steel tends to be a little soft. A hard, forged, tool steel kitchen blade is rare any more, since it can't be used commercially and because folks have forgotten how to care for carbon steel.
On the other hand, I own a couple expensive hand-forged steel knives and one maker recommended the Lansky system for maintaining a constant grind angle. That's what I've used on my hunting knives.
For kitchen use, I use the Spyderco Tri-Angle Sharpmaker to sharpen plain and serrated blades. Since most kitchen blades are relatively soft for the reasons mentioned earlier, I sharpen frequently.
IMHO, unless you have spent $200-300 for a knife, there really isn't much reason to become a sharpening wizard. I expect my knives to slice tomatos, not a silk scarf falling through the air. <grin>
Cheers!
Dave
This is what I have done. I bought some cheap knifes. So, I can learn to keep them sharp. I got a 20 dollar kitchenAid chef knife. The box says it is some kind of 420 ja stainless steel forged. Also, I got a Chicago Cutlery Santoku knife and a paring knife, Also stainless steel forged.
Once I feel I can keep these sharp. I plan on getting some Wusthof. I think the Japanesse knifes are great , from all that I have read here. But the sharping thing seems to be a bit more involved than I am will to do.
However, For the price , the knifes I got do Alot better than What I have being using.
Thanks to everyones post. I now have a game plan
Thanks William!
I wouldn't imagine much of a difference between the serrations on a Ginsu and a Forever Sharp knife despite the fact that each manufacturer seems to have created their own pattern in the serrations.
If you want to remove more material (for example, if you want to make the edge angle more acute for better cutting), you need something coarser than the stones that the SharpMaker comes with. I use an EdgePro Apex for this task, which is an excellent system, but more spendy that many people want to go at around $250. You can, of course, use a variety of coarse sharpening stones (diamond stones, water stones, oil stones, etc) if you have the skill, but the Edge Pro takes much of that need out.
If you want to go for REALLY fast material removing, you can pick up a cheap 1x30 stationary belt sander from Harbor Freight for about $40 and get a selection of sharpening belts from Lee Valley. This will also give you a quick entry into the world of convex sharpening if you want to go that direction.
I would stay away from any of the dedicated electric "knife sharpening" devices as some of them use very rough carbide bits that tear the hell out of your edge.
Similarly, I would stay away from Cutco.. they are WAY overpriced for what you get, which is a cheap steel (440A, IIRC) coupled with an edge you can't sharpen yourself. For a European style knife, try Wusthof or Messermeister. I'm not familiar enough with the Japanese knives to recommend a brand, but for a nice fusion of Eastern and Western styles, I really like the Shun Classic series. If you want to go WAY fancy, check out the kitchen knives made by Bark River Knife and Tool, available from www.knivesshipfree.com, DLT Trading, or a few other stocking distributors.
Finally, for a great community with in-depth discussion of all aspects of knives, from manufacture to selection to use, visit www.bladeforums.com and/or www.knifeforums.com
Enjoy!
Fox
Why does a Knife cut
The principle that is responsible for the amplification is essentially a force balance on the knife in the vertical direction:
Pressure*Area of knife edge on material = total vertical force pressed downward by user
As you can see, the knife edge with a small area results in a larger pressure transferred to the material and correspondingly, results in the fracture or splitting of the material.
There are also important considerations of the horizontal forces that occur from the tapered edges of the knife that push away the cut material so that the knife can continue cutting (dependent on angle of the blade edge).
Hope this helps.
here's a 24 pc set priced at 85 Euros (123 USD)
http://www.internet-webshop.com/webshop/huis-en-inrichting/detail/79/zwitserse-meisterbach-messenset-24-delig-in-luxe-koffer.html
never heard of the brand / name -
8 inch chef
7 inch santuko
10 inch slicer
4 inch paring
if you're into artisan bread - 10 inch serrated bread knife
as for brand name - all of the 'top names' are good stuff - but they do have different handle styles and it is very important the knife "fit" your hand. if possible get to a kitchen store and pick them up, handle them, see how they fit. if it is not comfortable in your hand, you likely will not "grow into it."
the Japanese style knives are typically thinner, lighter weight and are most appreciated by folks who like to spend a lot of time sharpening and honing their knives to razor blade edges. this is impractical for the average home cook. they can also get quite pricey.
get a "storage device" - block, tray, whatever - a $20 or a $400 knife that is just tossed in the junk drawer is not going to be worth a hoot in terms of staying sharp.
I keep my knives in a drawer laid out next to each other, with a double layer of corrugated cardboard at the back so the tips don't get whacked.
an awful lot of one's preference is what happens in _your_ kitchen?
butcher / chef style more or less fills the same role - a heavy duty get at 'em. rock&chop til you drop....
I managed for many years without the santuko style - but I find the flatter blade shape just the cat's meow for veggie prep - slice - dice. other than "mass and bone smashing" methinks it does a good imitation of the Chinese cleaver! the 7" santuko "blade flat" is about the same as my 10" chef's - but it's a whole lot 'handier' to work with.
the slicer is good for roasts, melons - big soft things.... one can hack away at a pork roast with a mini-Swiss Army knife - but a 10" blade slicing a 4" roast makes for more pretty.
same with the bread knife - if one only ever has to address a baguette, those cute 8" bread knives are fine. pick up a 8 inch round Bauerbrot, ya' need something bigger than the fingernail Swiss Army size....
but it all comes down to how much of what one is doing. I rarely buy anything but a whole chicken - and I'm fond of bone in (other) meats - so I'm very partial to my boning knife. not everyone buys half a cow, so . . .
Still think a cleaver is a better choice than a slicer. Has multiple uses, so in my kitchen it gets used far more often. How are you giong to cut an acorn squash in half if you don't have a cleaver? It's also far more effective at scaring children out of the way than a slicer...
Joan
Christina, bring me the cleaver!