The mountain city has always been famous for its sharpness, and it can even cut off the barrel of heavy machine guns unscathed. This is something that everyone basically knows.
As the saying goes, a good general, from a soldier to a general, may have tens of millions of people's blood in his hands, which is just in line with a poem by Cao Song in the Tang Dynasty: If you seal the Hou with words, your achievements will be ruined.
Similarly, a top mountain city, in the production process, consumes a lot of energy and a lot of steel is damaged in the furnace, which is just in line with our theme today. A great achievement will be a ruin, and behind any top-level object, or doing things to the extreme, the cost is often very large, and these foundations are unknown.
Today, let's take a look at the story behind the mountain city forging. Sword-making technology is still maintained by relevant technicians. Shortly after the end of World War II, the manufacture of swords was banned. It was not until the twenty-eighth year of Showa that the license to manufacture swords was obtained, and it was approved by the Cultural Property Protection Committee of the former Department of Culture. Since then, the production technology of swords has been gradually improved. Now, Gongru Zhaoping and Yueshan Yizhen, two swordsmen, have been designated as "national treasure" holders of important intangible cultural property.
The production of swords can be seen from the poems praising the imperial power system of the emperor in the past. At that time, China's sword making technology surpassed that of Japanese mountain cities. After entering heian period, the production technology of Japanese mountain city gradually improved and became a unique treasure knife. In the Kamakura era, the sword production technology was further improved, and it was divided into several different schools according to the different production technologies. It is from this time that these five schools are called Shancheng Stream, Big River, Reserve Stream, Xiangzhou Stream and MINO Stream. In addition, the number of grinders, scabbers and silversmiths who are as important as knife workers is small, but they still inherit the traditional production technology and are precious.
First: forging
The production of Japanese Bushido knives, that is, forging, is different. The following is the most basic forging method:
Material-The raw material of Japanese Dao is jade steel made by melting iron ore. Therefore, since ancient times, many famous technicians have produced high-quality iron ore. For example, Angang, a famous craftsman in Bocao, centered on the mountains of China, is just in front of Shaanxi.
Production of iron sheet-to make a 69 cm long knife, we must first prepare about 4.5 kg of jade steel. Part of it is melted and made into a rectangle, which is bonded with an iron "frame". The rest is put into the furnace for pulping. Put it in water, then evenly divide it into small pieces, then push it on the "melting rack", then put it in the furnace for melting, then take it out and gently beat it into thick plates, then heat it and flatten it, and put a steel chisel in the middle to make it fold in two. This practice can be repeated ten to twenty times, and the inclusions in steel can be discharged, thus reducing the carbon content to one fifth of the weight of the gland, about 95 grams. In the meantime,
Manufacturing of iron core-The manufacturing of iron core is slightly different from that of leather iron. When soft foam Ding Tie is added to the jade cymbal, the carbon content is reduced to 0.25% and the weight is reduced to one third of the original. This is the heart iron. Heart iron is slightly softer than leather iron.
Joint forging-after tempering, the skin iron and core iron can be made into a Japanese mountain city. The core iron is placed in the middle and the outer layer is covered with leather iron. This is the most basic method, and there are many methods, such as jiafu forging, roll forging, Ben San forging, four-sided blocking forging and so on. Here, take the commonly used Jiafu forging as an example to illustrate.
Su Yan-Jiafu forging is to put the tempered iron core in the middle, and this iron is wrapped outside. Roll forging is to put the core iron on it, put the epithelial iron on it, and bond it with borax in the middle, and wrap the core iron by beating the skin iron for forging. Put it in the fire and stir it while heating. This is the so-called "Su Yan".
Fire-making-further heating and flattening the "flat" prototype knife, thinning the blade, making the back of the knife stand up and slightly bending the blade, so that the general shape of the knife comes out, which is "fire-making".
Rough post-treatment-put the "Huozao" knife into a special vessel and carry out preliminary post-treatment on its shape.
Clay treatment-after the shape of the knife comes out, it needs to be evenly mixed with clay, loose carbon and water and smeared on all the blade parts of the knife body. Only when the soil is thinner and then dried can the grain shape be exposed and the blade be stronger and sharper.
Burning —— After the pottery clay is treated, dim the lighting at the forging site, put the knife into the furnace, heat it evenly, and put the knife into the water tank according to the degree of red burning of the knife body.
This link is the most exhausting link in the whole knife making process. Once it fails, all previous efforts will come to nothing. Of course, this is also the time when the tailor concentrates on his craft. When the blade is heated in the furnace, he should pay close attention to prevent the clay from being burned by fire. In this process, there is a one-third chance of failure, and the failed toolbar will not be used.
Adjust the camber-after forging, the craftsman should observe the camber of the blade to decide whether to adjust it. If the camber is too large, correct it to be smaller. Conversely, if the camber angle is insufficient, please correct it to be larger. This link is called camber adjustment.
The final treatment-the last working procedure of forging is rough grinding of the tool. In this link, it is necessary to check whether the posture of the knife body is defective. , and then with a knife box, post-processing with a file, punching. Finally, the craftsman chiseled his name with steel, and then the knife left the hand of the craftsman, and was handed over to the silversmith for shoveling, and the scabbard for scabbard grinding, which fully demonstrated the charm of Japanese knives. A good knife must be sharpened quickly, but the sharpening knowledge of the knife is too great, especially in Japanese mountain cities. Some Japanese mountain cities can only sharpen it a limited number of times in the whole service life, otherwise it will be completely destroyed.
Second: grinding
The most basic function of grinding sword is to make it sharp. Today's polishing is different from the past, more is to increase the aesthetic feeling of swords and swords, which requires superb technology. Polishing is the last working procedure, and the polishing of a good knife is very important, which is also of great significance to the damage of the knife body and the heat treatment process. It can be said that polishing witnessed all the previous processes. In this process, there is also a one-third failure rate.
Rough grinding-blades polished with rough grindstones, formerly sea grindstones, are now made of synthetic diamond grindstones. The knife is inclined on the grindstone, and the back is folded back from the handle to the tip, and grinded from the tip to the handle. Then use Omura grindstone to remove spots, and polish them in the order of knife back, knife back and edge grinding. So far, it is a grinding method for new knives. From the later stage, ordinary rusty knives and new ones also take the same approach.
Basic grinding-this stage is to remove the spots on the blade with a grindstone. From this stage, the coarse grindstone gradually turned to the fine grindstone, which, as a soft grindstone, was mainly used to sharpen the blade. However, hard grindstones are often used to grind blades.
Generally, the grindstone is ground from the place close to the body to the tip of the knife, and the corresponding grindstone is ground back from the tip of the knife. It is very important to polish the foundation. If the polishing is not sufficient, it will not truly reflect the characteristics of the mountain city, so high-level polishers often think that basic polishing is more important than polishing.
Polishing-This is a method aimed at the back and edge of the knife. It is polished with a thin steel bar called a polished rod. When polishing, it is wrapped with silk cloth and dipped in oil for polishing, so that the back of the knife and the edges and corners on the back of the knife are more shiny and can enhance its aesthetic feeling.
Grinding the tip of the knife-first grind both sides of the tip of the knife, and then wipe the tip horizontally with the grindstone for grinding the tip of the knife. Then spread five or six pieces of paper on the special workbench, and then polish it with a grindstone with a sharpening point of five centimeters long and two centimeters wide, and the polishing process will come to an end.
Third: make a white scabbard.
Material-Use cypress with less oil and moderate hardness as raw material. First, use a saw to cut out a board slightly larger than the blade and about four centimeters thick, and then divide it vertically into two halves.
Cut-It is very important to put the inner surface of the scabbard divided into two halves on the scabbard, then draw the shape of the scabbard with a soft pencil, then carve the back of the scabbard with a corner chisel according to the main line, carve the scabbard with a round chisel, and then cut off the defects horizontally with a small chisel. This process should be carried out in sequence, and the knife can be made only after it is confirmed that the knife can be inserted into the scabbard smoothly.
Bonding-After the last process, the two sheaths should be bonded together with adhesive. The rice paste should be carefully prepared and coated on the scabbard. Be careful not to expose the pulp in the sheath, and then tie the sheath tightly with a rope.
Post-treatment-After the paste is dry, it can be post-treated, that is, the scabbard is scraped flat with a planer to make its shape perfect, then the scabbard mouth and the handle are repaired with a knife to make them closely combined, then nail holes are punched, and then detailed cutting is carried out with various planers.
A top mountain city has a failure rate of one-third in forging, one-third in heat treatment and final failure rate in grinding. If these details are not handled properly, then the knife may be completely scrapped. The more difficult the manufacturing process is, the greater the failure rate will be. So it may take a month or two for a craftsman to make a knife, and this is just ordinary.