Xu Kui prepared all the raw materials, and Emi Yanagi also came to help, looking forward to it: "Master, this time you really want to use traditional craftsmanship to make a katana?"

After Su Yuan checked the materials, he said lightly: "Follow the customs of the locals, since you are in your one-third of an acre, you naturally have to use your craftsmanship." ”

Yanagi Emi's face was flushed, and she was very excited, she was finally able to see the highest level of katana casting, for her, Su Yuan was an omnipotent god!

Now that Su Yuan has completely mastered all the ancient techniques of the katana, he has the opportunity to try his hand and is ready to challenge other schools in full accordance with the ancient method.

The first step is to make an 80-centimeter-long knife and prepare six kilograms of jade steel. Part of it is melted and beaten in a rectangle, bonded to the iron stiff, and the rest is put into the furnace to beat.

Put it in water, then divide it into small pieces equally, then put it on the melt accumulation table and put it on the melting table, put it into the furnace again to melt, then take it out and gently beat it into a thick plate, then heat it, flatten it, and put the steel chisel in the middle of the two folds, and this practice is repeated ten to twenty times.

In the process, the inclusions are discharged, thereby reducing the carbon content to one-fifth of the weight of the gland, about 95 grams. During the smelting, it is also coated with plant ash and sprinkled with muddy water, which will help prevent the surface of the steel from decarburizing and speed up the healing of creases.

Xu Kui and Yanagi Emi did it, Su Yuan was monitoring on the side, and the little girl was dominant, and the level was changing day by day during this time, and this little thing was easy.

Then take out a piece of golden meteorite, which is the key to making heart iron, add the soft blistering iron to the jade negative chuan, and fold it several times to reduce its carbon content to 0.25%, and the weight to one-third of the original weight, becoming the heart iron, which is the lifeblood of the katana.

After the skin iron and the heart iron are smelted, the heart iron is put in the middle, and the outer layer is wrapped with the skin iron, which is the most basic ancient method, the armor forging, which has been passed down for thousands of years and endures.

Su Yuan took the small hammer and began to forge it with his own hands, putting the iron on the top and the leather iron below, bonding it with borax in the middle, and wrapping the heart iron by beating the leather iron for forging. It is thrown into the fire, and while it is heated, it is beaten and extended, and it is called Suyan.

Xu Kui cooperates with a sledgehammer, and according to the strength and angle of the hammer strike, the output is stable and the cooperation is tacit. After the extension, the prototype of the knife embryo is further heated and flattened, and the blade is thinned, the back of the knife is erected, the blade is slightly curved, and the shape of the knife is roughly appeared, which is fire.

Emi Yagyu next to him was not idle, carefully fusing yellow mud and cold spring water, and adding various recipes, this is the most mysterious earth-covering blade in the legend.

Su Yuan stared at the knife embryo, and at the moment when the light was the most dazzling, it was inserted into the covering soil, fully absorbing all kinds of trace elements, which was equivalent to eating the Ten Perfection Tonic Pills.

Then comes the time of the real technology, according to the traditional process, it is necessary to dim the light in the forging area, put the knife into the furnace, heat it evenly, and judge the best time for water quenching according to the degree of redness of the blade.

This link is the most laborious part of the whole knife making process, once it fails, the previous efforts are lost. When the blade is heated in the furnace, pay close attention to ensure that the clay is not burned by the fire. In this process, there is a one-in-three chance of failure, and the failed blade will not be usable.

Su Yuan's face was full of light, it was easy to grasp the opportunity, this time not only to cover the soil and burn the blade, but also to try the method of oil quenching, to see what miracle the combination of Chinese and Western would produce?

One soil covering, one water quenching, one oil quenching.

Cycle

Three times!

Xu Kui and Liu Shenghui are full of obsession, and the drudgery of striking iron seems to have become a kind of enjoyment, flowing smoothly and calmly, without a trace of fireworks.

Especially the sense of rhythm, when you close your eyes, it is like a big bead and a small bead falling on a jade plate, crisp and pleasant, and it is a symphony for three days.

Su Yuan was engrossed, and the knife embryo was covered with ice and fire, slowly changing the angle, and gradually becoming a meniscus shape, without any external force, all relying on natural magic.

A famous knife, the most beautiful is the arc, the antelope hanging horns, the stroke of genius!

After completing the last oil quenching, put the knife embryo in the warm fire to return the air, Su Yuan sent a breath, and it was basically completed, after the traditional method of the knifesmith checked whether there were any defects, he put on the knife box and engraved the name with a steel chisel, and then the knife was to leave, and it was handed over to the silver master for the blade, the sheath master for the scabbard, and the grinder for grinding.

In the island country, this is a complete industrial chain, division of labor and cooperation, especially grinders, whose status is noble, no less than that of famous knife makers.

Since the Muromachi period, they have been a noble profession, and they have been continuously recorded in history, recited and revered, and even erected monuments. Even now, the social status of a professional researcher is not below that of a professor at the University of Tokyo!

Knife grinding has long been a skill with a complete cultural and technical system that is almost independent of knife manufacturing, and has become a great national cultural heritage.

Su Yuan rested for a while and picked up a stone, this is a multi-volcanic country, many of the stones used to sharpen the katana are volcanic stones, and even specially summarized and developed a lot of grinding stone veins, some of which are as high as about 6,000 meshes, which are extremely delicate.

For example, the piece of inner material in the hand, before cutting, must be carefully picked off the stone tendons and cut into thin slices when used, otherwise it will scratch the ground knives, resulting in the loss of previous efforts, at least 2,000 US dollars per gram.

Even now, the most common grinding cost of a katana will cost the island countryman's salary for two or three months, which is equivalent to more than 20,000 yuan.

After a good researcher gets the work, the first thing to move is not the hands, but the eyes and brain. First of all, determine what period and whose work it is, at least what genre of work it is. Then look at the flaws and damage, and then decide what method to use to better represent everything on the knife.

According to the Ami family, which has been inherited for a hundred years, when a researcher gets a knife, he should not start it first, but should look at it for ten days, or even twenty days, until he understands the knife before he can do it, which is almost Zen.

For example, there is a big difference between a newly forged knife and a finished knife that has been resharpened. Newly made knives do not need to remove rust on the surface and rust spots that may penetrate deep into the blade, but to correct some forging defects, such as forging marks or pickaxe lines that are not straight, a number of tools and processes are required.

Antique knives may have other problems, such as side bending, which cannot be returned to the furnace or cold forged, otherwise it will seriously damage the knife body or even change the crystal structure, so only real masters are qualified to accept the job.

Su Yuan took out the knife embryo again, cleaned it, and asked Yanagi Emi: "In the past, your Yanagi family was looking for the Ben Ami family to polish?"