Knives in one form or another are used by us every day and everywhere. Their main task is to cut something whole into smaller components, because one of the key indicators of the tool’s functionality is its sharpness. Using poorly sharpened knives is inefficient and dangerous. A blunt blade requires more pressure and often deviates from the cutting line, not allowing to achieve the required accuracy, and, moreover, can lead to serious injury as a result of slipping. Therefore, the answer to the question of how to sharpen knives correctly will provide not only comfortable work, but also personal safety.
Paper Against Steel
In order to determine whether a sharp blade is sufficient and whether it needs sharpening, you can conduct a simple "paper" test. Take a knife in your hand and try to cut a sheet of paper hanging without tension, moving from its top edge down and slightly to the side. In the case of an uneven cut, the blade needs fine-tuning of the cutting edge, and if the blade tears and does not cut through the paper at all, then it's time to sharpen it.
Frequent use and improper care can make any, even high-quality knives unsuitable for work. How to sharpen a blunt blade using the most affordable devices, we will understand in more detail.
Knife coeval - whetstone
This is perhaps the oldest, but not the worst way to handle a dull blade. How to sharpen knives with a bar, in theory everyone knows, but, alas, not everyone achieves a good result in practice. First, let's figure out what criteria the grindstone itself must meet.
- The bar should be larger than the cutting edge it processes.
- The working surface should not contain bumps and chips.
- For sharpening, it is better to use a stone having different grain sizes on both sides.
Faithful hand is a friend of a sharp blade
The blade sharpening procedure is the process of removing part of the metal to form a thin cutting edge. For preliminary (rough) removal of the edge, an abrasive with coarse grain is used, and the final fine-tuning of the blade is made already with the fine-grained side of the stone.
To understand how to sharpen knives correctly with a bar, you need to understand that the main difficulty in this work is the strict observance of the angle of inclination of the surface of the blade to the abrasive stone along the entire length of the processed edge and on both sides. This process requires certain skills, so in order not to spoil your favorite knives, practice on those that you do not mind.
Choosing a blade sharpening angle
The value of the angle of the bevel of the blade at the knives can vary and obeys one simple rule: the blade is sharper - the smaller the angle of sharpening, and most often from ten to thirty degrees. At the same time, it is impossible to say unequivocally how to sharpen knives correctly (in terms of the angle of inclination) to obtain the maximum effect, it all depends on the scope of the blade. The best blades do not have to have an ultra-thin cutting edge that is more prone to destruction. For example, a thicker knife is able to withstand, without breaking, significant loads, and due to the chopping moment, to separate more massive objects. In this case, the true value of the blade is determined by the quality of the material from which it is made, and the technology of its heat treatment. The most common angle for European sharpening is within twenty degrees.
Little tricks for practicing sharpening skills
Since it is possible to sharpen knives correctly with a bar only by observing a constant sharpening angle, it is justified for beginners to use the template to develop skills. Its role can be performed, for example, by a metal coin.
Another way is to fold a sheet of paper in half diagonally, getting an angle of 45º, folding it again, we will form an excellent template with a bevel of 22.5º. Now it is enough to place it with the base on the grindstone, thereby creating an emphasis on the blade. This simple device will allow you to learn the secret of how to sharpen knives on a bar with maximum efficiency.
Slow and detailed whetstone
The sharpening process itself does not like fuss. Before sharpening the knives with a bar, it is lightly greased with mineral oil or moistened with soapy water (either one or the other, but not at the same time), which will facilitate the passage of the blade over the stone, as well as protect its pores from clogging with steel chips. Lock the block with the coarse-grained side up, placing a rubber mat or damp paper towels under it. Take the knife by the handle and, turning the cutting edge away from you, place it on the grindstone at the desired angle. Holding with the other hand in the middle of the flat side of the blade, smoothly, without strong pressure, move the knife along the abrasive stone in a linear or circular motion from the handle to its tip. To check if the first side is pointed, gently slide your thumb perpendicular to the edge of the blade. The presence of burrs all the way from the handle to the tip indicates sufficient refinement of the metal and the achievement of the necessary sharpness of the processed edge. (Safety tip: do not slide your finger parallel to the blade).
For quality control during sharpening, you can use a permanent marker, which will easily allow you to visually determine how to sharpen the knife, removing metal only in the places you need.
After that, the blade can be turned over and the whole process repeated for the second side. To finalize the knife, turn the grindstone with the fine-grained surface up and repeat the whole process on both sides of the blade until the burrs are removed.
Pros of using a grindstone:
- High adaptability (the ability to sharpen the blade at any angle).
- You can sharpen knives with full emphasis.
- Most stones are coarse and fine grit, which allows you to adjust the amount of metal removed during sharpening.
- Low cost of a tool-grinding bar.
Minuses:
- To ensure a smooth edge, the knife must be kept at the correct (constant) angle, which requires good practice.
- It may take a long time to restore a very blunt blade.
Using waste to finish the knife
Alternatively, you can use musat to fine-tune the blades. It is a long, most often metal, rod of round or oval cross section with small notches or abrasive spraying. The tool is not designed to remove a layer of metal, it only trims the edge of the blade. Its main task is to correct the burrs resulting from rough grinding, or during operation of the knife.
How to sharpen with musat, consider in more detail. For safe use, hold the sharpener upright, pressing the tip firmly against the table. Place the heel of the blade on the musat and slightly tilt the tip of the knife up. Observing the given angle of inclination between the blade and the tool, with a wide movement towards yourself and down, drag the edge of the blade from the heel to the tip over the entire surface of the garbage. Repeat this movement on the other side of the knife. Four to five passes on each side will give the cutting edge a perfect shape.
Knife sharpening with materials at hand
There is a situation when there are no necessary accessories nearby for sharpening a dull blade. Then the question arises: is it possible to sharpen knives with something else?
Any ceramic dishes, for example, an ordinary coffee cup, can do this task well. Putting it on the table upside down, you can pretty well sharpen the blade of a small knife, using the unglazed edge as a grindstone. In this case, all actions will be similar to working with the bar, only this process will take a little longer.
Mechanical sharpeners - cheap and cheerful
It is very effective as a home knife sharpener to use various types of mechanical sharpening devices. Typically, this is one or more pairs of parallel abrasive discs, creating a V-shaped profile at the intersection. The blade extends through the slot of the sharpener, uniformly removing a small layer of metal on both sides, forming an almost perfect edge with symmetrical sharpening angles.
The advantages of the mechanical sharpening method include:
- High walls. They securely hold the knife in a stable position, allowing the blade to pass through the abrasives with uniform pressure.
- Strict adherence to a given angle, which does not require the development of professional skills.
- High sharpening speed, as the edge surface is processed simultaneously on both sides.
- The low price of the device.
Of the minuses:
- Lack of variability (it is impossible to change a sharpening tilt).
- Even the best manual sharpener cannot repair significant damage to the blade (for example, remove chips).
Quick and comfortable electric knife sharpener
The dumber the blade, the more metal will need to be removed to form the cutting edge. When using a hand tool, this can take a lot of time, and in the case of a bar, it also implies the presence of certain skills. If there are a lot of blunt knives, but not enough time, there is nothing left to do but sharpen the knives on the machine. There are a great many types and models of such devices.
For household needs, the most convenient option, guaranteeing excellent quality, is the use of an electric sharpener. These devices are easy to use and are based on the same principle as their mechanical counterparts. The only difference is that the abrasive wheels that remove excess metal from the knife rotate by means of an electric drive. After plugging into the power outlet, it is sufficient to slowly and without jerking draw the blade through the desired slots, repeating this step several times. In this case, the knife must be held securely, but without pressure, the machine itself will do all the work.
Advantages of using electric sharpeners:
- High grinding speed.
- The spring-loaded guides limit the movement of the knife so that the entire edge stably contacts the abrasive at an exact angle.
- Aggressive first slot can quickly restore significant damage and narrow the edge to a sharper edge.
- The presence of several grinding grooves with different grit allows you to control the degree of sharpening.
Minuses:
- The blade grinds faster.
- It can not be used for knives that have an emphasis, as there is a restriction on the blade feed.
- The high price of the device.
Meat grinder and her unusual knives
Such an indispensable thing in the kitchen as a meat grinder also has knives (albeit somewhat unusual in shape), and they, alas, also have the peculiarity of being dull. Most of us do not wonder: how to sharpen a meat grinder knife, but simply buy a new kit in the store. Moreover, bringing them into working condition is not such a big problem. It is only important to understand the principle of operation of this device.
The mechanism is a kind of scissors, using two cutting edges for grinding. One of them is a group of interconnected cutters (movable knife), in the form of mill blades, and the second is a flat mesh surface (fixed knife) through which the crushed product comes out. Therefore, in the event of a decrease in the quality and speed of grinding, both elements need to be sharpened. At home, this procedure can be carried out by simply grinding the wide surfaces of the movable and stationary knives of the meat grinder on any grinding tool you have (a bar, a circle, sandpaper) with a gradual decrease in the size of the abrasive grain. The only condition is the width of the work surface. It should cover the entire machined plane of the knives, ensuring uniform removal of metal. This is necessary for subsequent precise mating of the cutting edges of a pair of knives.