How to sharpen a ceramic knife at home

From the very beginning of human civilization, it has been accompanied by a very important tool - the knife. It was made from different materials. Over the past centuries, the undisputed leadership in metal products. But at the end of the 20th century, the Japanese began to release a new product that immediately conquered the market. These are ceramic knives.

Properties and features of ceramic knives

In the early eighties, Japanese technologists drew attention to the amazing properties of zirconium dioxide, which is a derivative of the zircon mineral.

The main feature of zirconia products is high hardness. On the Mohs scale, the hardness of diamond is 10. The hardness of zirconia ranges from 8.2 - 8.5. At the same time, this indicator is 6.2 for hardened steel.

Another attractive property of this mineral is that it is chemically neutral.

These knives are called ceramic first of all according to the manufacturing technology. They are made from zirconia powder by pressing in special forms and subsequent baking in an oven at a temperature above 1500 degrees.

The advantages of ceramic knives

1. Due to the high hardness of the material from which they are made, these knives maintain sharpness of the cutting edge for a long time;
2. With such knives, it is easy to cut products, even the softest ones, which are crumpled with an ordinary tool;
3. They are chemically neutral, therefore they do not absorb themselves and do not leave extraneous odors on the products, moreover, they do not destroy the beneficial vitamins present in the processed food;
4. Ceramic knives resist corrosion and do not oxidize cut fruits and vegetables;
5. The weight of these products is significantly less than that of metal counterparts.

Disadvantages of Ceramic Knives

1. Despite its high hardness, under certain conditions a ceramic knife can be brittle. They should not cut frozen foods and bones, as well as make chopping movements, because the cutting edge may crumble or the blade may break at all;
2. Such a knife is not universal, it is only good in the kitchen, and its cost is higher than that of most metal knives;
3. Sharpening a ceramic knife is a rather complicated process. A person without skills may not be able to cope with this and will be forced to look for a special workshop.

Types of Ceramic Knives

When deciding to buy a new ceramic knife, you need to know what types of these products exist and how they differ from each other.

First of all, you should pay attention to the manufacturer. The undoubted leaders in this segment are Japanese masters. When buying a Chinese product, it must be borne in mind that the knife can be more fragile and short-lived.

Knives made of different starting materials differ significantly. Black ceramic knives have greater hardness and durability than products with a light shade.

Ceramic knife sharpening methods

Given the high hardness of the material from which the ceramic knives are made, grinding and polishing stones and diamond-coated stones are required to sharpen and polish them. It is useless to use ordinary grinding materials, they will not leave any trace on the surface of the knife.

The second condition that must be observed is to perform sharpening in three stages. At the beginning, the sharp edge is processed with a coarser material, for a grindstone it will be 3000 grit. Then grinding is done with a tool with a grit of 5000 and this work ends with polishing with a stone with a grit of 6000.

If you do not finish grinding and polishing with fine-grained stones, then the cutting blade of a ceramic knife may crumble after a few days of using it in the kitchen.

The easiest way to sharpen a ceramic knife - This is to use a special electric grinder, which is sold in the same place as the knives. In this case, you need to know which sharpening for a particular knife is required - one-sided or two-sided. In accordance with the required method, it is necessary to choose a mode. In such devices, all the angles needed when processing knife blades are adjusted.

Quite quickly, you can sharpen a ceramic knife on a grinder with a circle coated with diamond chips with a grain size of not more than 40 microns. For such a fragile material such as ceramics, some rules must be observed:

• the spindle on which the circle rotates should not be loose, there should be no beating of the grinding wheel;
• sharpening is required to be done at low speed;
• during sharpening, minimal efforts must be applied to press the blade of the knife against the rotating disk, and during the whole process they should be the same;
• sharpening angle for kitchen knives is accepted in the range of 18 - 25 degrees;
• sharpening the blade is required from the handle to the tip, and the movement is slow without jerking;
• after processing on the grinding machine, the ground surface should be polished;
• Before starting work, you need to make sure that on one or two sides the blade of the ceramic knife will be processed.

More time and effort will be spent if it is decided to straighten the knife blade with the help of whetstones or bars. In this case, the tool requirement is the same. Only diamond coated bars are used. The granularity of the bars should be from large - for primary processing, to fine - for subsequent grinding and polishing of the surface. For the convenience of work, bars of at least fifteen centimeters in length are selected.

• During sharpening, do not apply large lateral forces to the blade of the knife. Pressure should be gentle and uniform.
• First, a blade near the handle is applied to the bar and then a leisurely movement to the edge of the knife occurs. Movement is made in only one direction.
• The angle of sharpening for a kitchen knife is 18 - 25 degrees.
• If the sharpening was one-sided, then, after its completion, by turning the blade over on the other side, the resulting scoring is removed with one movement on the bar.
• It is necessary to sharpen the knife on a wet bar, for this it is recommended to lower it first in the water for 10 minutes.

Despite certain difficulties in sharpening ceramic knives and the need to be careful when using them, this tool is rightly called the invention of the 21st century. Their absolute environmental friendliness, lightness and high sharpness make ceramic knives indispensable in the kitchen. The best result is achieved by housewives and professional chefs using both ceramic and traditional steel knives. Each tool is used for a certain type of work. With this attitude, ceramic knives serve for many years, without requiring additional care.

Video: how to sharpen a ceramic knife quickly