How do you sharpen a knife? First unless you have chosen your knife well, you might as well stop now. If you have a knife that you can't get sharp or that wont stay sharp, make a box knife out of it or give it to your worst enemy. For other knives, there's hope, provided you think about what your doing and proceed.
Let's consider the material of workmanship that goes into a knife. You will find that mostly there is stainless or carbon steel. You may on special occasions encounter Damask steel (this special knife material is formed by taking a sheet of steel, bending it back on itself and rolling or hammering it to the thickness of the original single sheet of steel. The process is repeated eight times until there are 256 layers or nine times when there are 512 layers of steel. The resulting surface has what appears to be refractive marks in the surface which are in fact where individual sheets were thinly formed, more-so than the underlying sheets.)
There are different grades of both stainless and carbon steel. Some is more suitable for knife making than others. The knife making industry seems to prefer using stainless, The really cheap stainless steel knives while they look good are almost impossible to sharpen. When they come from the factory, they are as sharp as they will ever be. I prefer carbon steel and the higher carbon content the better.
A good knife's tang is an extension of the blade and is that part to which the handle is attached. If the tang doesn't go the length of the handle, the knife will probably not be worth having. And the finger guard should be formed right from the same metal blank as the blade and tang, not something welded or swaged on. The guard is something to keep you from cutting yourself in the case the handle slips in you hand and is a good idea, regardless of how dexterous you may be. Having said this, some knives used in the packing industry are called boning knives and they lack a guard. It certainly is cheaper to forge a knife blade without the guard, so in some cases it's added as an additional embellishment when the handle is attached or left off entirely.
Now the handle is of special concern. There are some miracle materials that have been developed which are useful for making knife handles and they are good. However, a rosewood handle or other wood has a nice appearance and is most serviceable. If after tens of years the wood is badly worn, it can always be replaced at a nominal cost. (It is interesting to note that while claims have been made for the synthetics as being more sanitary, a study at a leading institution found to its surprise that a wooden surface was less inclined to culture bacteria than a plastic surface.)
The means for affixing the handle to the blade should always be by either brass or other metal rivets. Neither glue nor having the blade bonded into a plastic handle is satisfactory in my judgement.
Let's address the shape of the blade. For it's intended purpose, a knife should always be larger and heavier than the job calls for. This protects the user from forcing the issue and perhaps injury. A good 12 inch carving knife should be about one and one half inches wide at the butt end, and taper to a not too abrupt point. On the other hand a boning knife should be about 6 inches long and no more than one half inch wide at the butt end, it must taper to a fine point. With these two knives, there is little need for others.
The taper of the blade is important. This refers to how the blade tapers from the thickest part to the cutting edge. Most cheap knives are flat with the cutting edge double angled to a thin cutting edge. The problem with this is that once the knife becomes dull, it is almost impossible to sharpen as one has to wear away the steel from the entire surface of the knife before the cutting edge meets the stone. A well-forged blade tapers from the top of the blade to the cutting edge. The intended used dictates which form is best. For most pocket knives and kitchen knives, a gradual taper is best all round. The other two blade shapes encountered are a hollow ground blade where the surface of the blade is slightly concave (dips inward), or a blade where the surface is convex (curves outward). The concave shape is ideal for those that sharpen their knife on a grinding/polishing wheel as the concave surface matches the wheel's curvature. This is also the shape ideally chosen for the straight razors of old. In the case of a carving knife where the blade never meets a hard surface, a hollow ground blade is much preferred by some, as it takes only a few strokes on a steel (see below on how to use a steel) to realign the edge and return it to its original sharpness (not unlike the use of the razor strop to put the finishing edge on a straight razor).On some expensive hunting knives and kitchen knives you will find this blade taper. I don't favor this shape as it is difficult to true the edge in the event that the blade has been damaged and a large amount of steel must be removed to produce a straight cutting edge. Not often found in knives, the convex form is ideal for a heavy cutting instrument, as example, a woodsman's axe. The chopper wants the blade to cleanly enter the wood and then spring back from the wedged cut so that the blade can be easily removed from the wood for the next swing. Look at a double blade axe the next time you are in a hardware store and you can clearly see the convex curve. Cheap boy scout axes just wont work as well.
In addition to the basic shape, the blade angle, where the cutting edge is formed from the supporting material is critical for the knife to perform as intended. If the edge is feathered from the base to the very edge, the knife may be very sharp, but it won't stay sharp long. This may be OK to many users, but for a production worker it is better to have a more substantial edge on the knife. Accordingly, they start with a knife form where the sides at a cross section of the knife away from the cutting edge are essentially parallel, i.e., the knife is shaped to have a reflection angle of about 15 degrees, then the material is shaped to have a transition angle of about 20 degrees and finally at the cutting edge the cutting angle is about 25 degrees. When you think about this the blade changes from two sides which are essentially parallel to a cutting edge which is at 60 degrees to the blade itself. Production workers get and maintain their knives' cutting edges by using mechanical sharpening tools that are for the most part unnecessary for the rest of us. These tools quickly wear away the blade and the knife may be discarded in a matter of weeks. My knives are too dear to treat in this manner.
Probably everyone has a "stone" of some type. It may be a fancy Arkansas stone in a fine rosewood box or it may be the concrete step at the front door. They all work by the same principle. The stone wears away the steel to produce a cutting edge. Regardless of which stone you use don't use oil, use water. Oil will clog the pores of the stone and instead of sharpening the knife you will be polishing it. That's fine if the knife is razor sharp to begin with. After you have used your stone, wash it off. (For those that insist on using oil, after all some of the stones are called "oil stones", the best and only oil that should be used is mineral oil. It doesn't oxidize and polymerize and clog the pores like a vegetable oil will. Regardless, always clean the stone after use.) Now if you can spring for the money, the best buy you can make is a diamond faced metal sharpening (stone). The advantage of a flat surface rather than a rod is that you can control the angle where the blade meets surface more accurately. (Too bad if you just did a great job of sharpening the blade and then with one or two injudicious swipes on a rod you distort the cutting edge rendering it less than sharp.)
What happens when the blade meets the stone? Assuming that you have already removed the excess steel and are down to a fine cutting edge, as you draw the knife across the stone (pulling the blade toward you), the stone removes microscopic "chips" of steel. In addition, friction between the blade and stone, work hardens the metal making it more durable. Back to the mechanical sharpeners used in slaughter houses by production workers, these devices rotate away from the user and the blade is laid on the grinding surface. This results in pulling the steel from the edge. It also results in producing a fine "burr" which must be removed by pulling the blade toward you as just Described to finish the sharpening process. There are some that prefer to move the blade away from you as in the case of the production worker. Frankly, it doesn't make sense to me, because you eventually have to go ahead and sharpen the knife by pulling the blade toward you. Regardless, if you look at the knife edge under a microscope, you will discover that it looks like a saw blade with tiny teeth that are not aligned very well. Now is the time to carefully stroke the knife on the stone, or better yet use a steel to whip the teeth into line. A smooth steel is great for this job as it doesn't risk damaging the nicely sharpened edge you have just attained.
How you hold the knife while sharpening is important, and it can make the sharpening job easier. Grasp the handle between the fingers and thumb with the index finger outstretched and lying along the blade. In this grip, you can put pressure on the blade with the forefinger, while having a firm grip on the handle. Now, placing the stone on a table or other supporting surface, draw the knife at a forty-five degree angle across the stone, starting with the butt of the knife resting against the stone. This way, the maximum surface of the stone is in contact with the blade. Deftly pull the knife toward you, placing a little pressure on the blade while holding it so that the blade is not quite flat against the stone. Do this several times, then reverse the motion by changing your grip on the knife, and sharpen the other side of the knife.
Back to Damask steel for just a moment. The reason that these blades are so sharp is the result of the minute layers of steel lying almost in parallel to one another. As the blade is sharpened, the different layers are revealed and each in turn presents a tooth for cutting. Thus there is a grain to the material which aids in its performance. Likewise, steel whether stainless or carbon also has a grain which is produced as the material is rolled at the mill. This crystal structure is important in the getting and keeping of an edge. Unfortunately, there is no way of knowing the orientation of the grain in the knife you buy.
The art of steeling a knife is best described in Max Cullen's book, "How to Carve meat, game and poultry." "Steeling requires a definite technique, for anything but the right way will produce the exact reverse of the end desired, which is to straighten the edge of the blade. Ignore the rules and you will move one step forward and two backwards. So, while it may prove irritatingly awkward at first, until you have acquired the knack of this fairly rudimentary mechanical coordination, your knives will be no better than exasperating object lessons of the law of diminishing returns and unjust accessories to the finest rib roast of beef." He goes on to describe the exact process of how to properly steel a knife.
What the beginner has most difficulty in understanding is that the steel is held in a position upward away from the body and the knife strokes the steel in a smooth action bringing the shank of the blade against the tip of the steel and continuing the motion to bring the knife downward along the entire length of the steel. As the blade moves along the steel it aligns the edge so that it is straight, it is not sharpening the knife (sharpening requires the use of a stone to remove metal from the edge). When the tip of the knife just passes the hilt of the steel, a repeat passage along the opposite side of the steel trues the blade further. Only a couple of strokes is required on a sharp knife to maintain its maximum cutting ability, but the process should be repeated frequently. The angle of attack is most important to avoid doing damage to the knife's edge. Starting off it is better to have a very small angle, i.e., where the blade essentially lies flat on the steel. With practice, one adjust the angle upward to about 25 - 35 degrees (remembering that 90 degrees would be putting the blade straight into the steel at a "right angle"). Cullen points out that the motion should be smooth and with a light touch, not unlike the soft but sure stroke of the practiced violinist in moving the bow across his instrument.
An old wive's tale which has some merit is to rub a lemon or vinegar on a dull knife to make it sharp. This cleans the metal and probably sharpens the small "saw" teeth of the edge. If you try this, remember to wash and dry the knife before it is put away. (This was also suggested as a means to rejuvenate a worn out file.)
Now as most boys know, there are several means by which one can determine if the knife is truly sharp. First, if you lightly hold up a piece of paper and pull the blade across the edge, it should cut smartly through. (This is not actually recommended for the finished job of sharpening but as an intermediate assessment to see how much further work is required. The wood fibers in the paper will miss align the teeth and call for the steel.) The second, is to see if the blade will shave a few hairs from the forearm. (Ladies will have to find some other appendage for this test). And the third, which I prefer is to hold the blade to the light. If you can see the edge, you are nowhere close to having the knife as sharp as it can be.
The bane of all good knife makers and I hope knife users, is the electric knife sharpener. Once used, the knife is ruined! However, the cheap knife maker loves these devices as they guarantee sales of further cheap knives.
Good luck on sharpening your knife. A good knife is a family heirloom and should be passed from generation to generation. And in passing, look in the kitchen of estate sales, sometimes you will find a knife well worth having for a fraction of the cost of a new knife.
GAMES - A favorite knife game played on the schoolyards when I was growing up in East Texas was a game called "splits". Since every kid carried at least one knife (usually one that was kept razor sharp by constant honing and another for actual use and game playing), this game was particularly popular in the spring time. The way it was played was open to some latitude, but mostly, two boys stood about three feet apart, facing each other. The feet were together. The first player threw his knife at a target no-more than twelve inches from the others foot (either right or left). If the knife failed to stick up in the ground or was more than twelve inches away, the thrower forfeited his turn. Otherwise, the target foot was moved so that the sole of the shoe touched the knife where it stood in the ground. Now it was the opponent's turn. As each struck the intended target, one had to stretch wider and wider until one or the other could not stretch to the knife embedded in the ground, or would topple over. Either way, the winner remained standing. While we played this game during intermission, lunch period and after school, I never knew of anyone to have been struck in the foot.
MAKE YOUR OWN RAZOR (OR KNIFE) STROP - A. W. Lewis describes in his book, Basic Bookbinding, how to make a very serviceable strop. He suggest starting with a piece of wood some two inches wide and about twelve inches long. A bit longer (sixteen inches) is preferred so that a handle end can be provided for hanging up on the wall or holding the strop. Wood that is fairly thin (ca half inch) and will not warp (oak or maple are ideal but good yellow pine works as well.) Better yet is a free paint stirring stick from a supplier of paint. To one side of your strop glue a piece of leather, finished side attached to the wood, with the rough, flesh side showing. On the opposite side glue a piece of ordinary fine emery cloth. Here is Mr. Lewis' secret: to the open pores of the leather strip, add a bit of fine emery paste, the kind that you can buy at an automobile parts store as a valve-grinding compound. A bit of water added to spread the paste and you are ready to put a fine edge on your blade which can be used to shave or whatever. In the mid 1800s, compounds were sold to condition razor strops.
Telephone numbers for suppliers of sharpening equipment:
Wet Stone Sharpener - Wen Products 800-736-4936
Flap Sanders - Hantover 800-821-2227
Packer 800-279-7326
Koch 800-456-5624
Diamond Embedded Stone - Eze-Lap 800-843-3815
Ace hardware in some areas of the country sells Diamond sharpeners. I have ordered diamond pocket sharpeners from the Houston Knife Company.
In addition Cabala's of Kearney, Nebraska has a diamond sharpener that includes three different surfaces for either removing a large amount of material or in honing the edge to a fine finish. Call Cabala's for their catalog. 1.800.237.444 (This is a good source for camping, hunting, fishing, and boating supplies!)
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