Ning Yu saw that the thunder camel finally ran away, and he no longer deliberately angered him, but sighed: "It's not that the kid doubts the master's ability, but the times are advancing, dare to ask the master, what is the difference between today's cannon making method and the cannon casting method in the pre-Ming Dynasty?" ”

Lei Huozi was speechless when asked, so he had to say: "It's not easy to make cannons, as long as it's easy to use." "I don't have the confidence to speak so much.

Ning Yu pressed forward step by step, and said: "I look at today's green camp artillery, all of them are brittle and hard, and the explosion accidents have occurred repeatedly, and the soldiers dare not put ten percent of the gunpowder, every time they fire the artillery, they only dare to put in five points, and even some gunners only put three points, what is the difference between this kind of medicine and fireworks?" ”

"In order to increase the power, the wall of the artillery barrel was constantly thickened, and thousands of catties of general cannons appeared, but the real power of this kind of cannon is really worrying, and it is inconvenient to transport, it is really useless. In the future, the method of casting cannons needs three points, the lighter the cannon, the more refined the workmanship, and the greater the force. ”

Lei Huozi said in a sullen voice: "But now it is limited by the pig iron used in casting cannons, and it is inevitable that there will be honeycomb holes on the cannon body made of this kind of pig iron, which cannot be smooth, and it is difficult to carry out shovel grinding, so it is naturally not fast when firing guns." But if it is made of wrought iron, there are more problems, first of all, this wrought iron cannot be cast, it can only be made..... Forget it, what are you doing with this, my old man believes you, you are an insider, you can fight whatever you say. ”

Ning Yu knew that the most important thing now was to cast a cannon, as for this iron-making matter, he could put it at a later stage, and then solve this important cannon first, so he said sincerely: "Master Lei, the important thing I said about the former is that the clay fan takes longer to make, and the clay fan can only be used once, and this time the cannon needs a lot of clay fan, so it will naturally be delayed for a long time." Then you can choose an iron mold casting cannon and use an iron mold instead of a clay mold. ”

"Iron mold? Swage! Lei Huozi's eyes lit up, he is a master of this way after all, this figure is like piercing the window paper, now a simple click, the heart has a bottom.

Lei Tuozi was in a hurry, and he turned over at the moment, ignoring Ning Yu on the side, and shouted at the men who were casting farm tools: "Clean up the guys, cast cannons!" ”

Those men stopped their work and began to get busy in and out, originally this was the cannon casting workshop, so all the materials needed for the cannon casting were all available, and the drawings were also available, so they all pulled out and began to make preparations.

Lei Tuozi slumped, and then knelt down to Ning Yu in a trembling manner, and said: "This time I got the guidance of my son, if I can do it, I am grateful!" ”

In these years, craftsmanship is the guy who eats, and it is also life. It is precisely because of this skill that he can support dozens of people in this family, and he can also accept a few apprentices to support his retirement. Now that Ning Yu is telling him a craft, how can he not be grateful to Dade?

Ning Yu was also not polite, he knelt down and said, "Master Lei, what the kid proposed is just an idea, and how to do it depends on your side to study it carefully." ”

Lei Tuozi continued to kneel and said, "Please also ask Gongzi to stay here for a few more days, and I hope Gongzi can give more guidance." ”

Ning Yu thought that he could quickly cast the cannon, so he stayed behind to give instructions.

In the following days, Ning Yu began to cast cannons based on the memories of his previous life, and then combined with Lei Tuozi's experience.

The key point of the iron mold casting method is to cast the iron mold first, Lei Tuozi and others will first make the clay mold, and then use the lathe plate to spin the inner surface, so that the surface is smooth and clean, the shape is regular, and it is dried for later use.

The mud mold is made in less than a day's work, and then the clay mold is used to turn the cast iron mold, the muzzle of the section is inverted on the mud plate, one of the petals is filled with mud, after drying, the mud plate is covered, the shape is tightened, and a petal of the first iron mold is obtained after pouring.

Then another iron mold is cast by this method, and then poured section by section to cast a complete set of iron molds with layers of tenons and tenons. At this point, it only took four days.

Lei Tuozi looked at the iron mold that had just cooled, his heart was extremely excited, and he said respectfully to Ning Yu: "Childe, you can first apply a layer of mud and sand paint, and after making a mud core, you can pour the cannon body." ”

Ning Yu thought for a while and ordered: "You can add some coal dust to this paint to reduce bubbles." ”

Lei Tuozi was overjoyed and said: "What Gongzi said is very true. Then he instructed his craftsmen to prepare pulverized coal.

After the mud core was completed, Lei Tuozi personally poured molten iron into it, and among the smoke, Ning Yu looked at everyone's dark faces, and couldn't help but smile, these people are the real treasures of the Ning family.

The reason why Ning Yu is so polite to Lei Tuozi is not because in this year, technical talents are scarce and precious?

After the molten iron is poured and slightly solidified, Lei Tuozi asks the craftsman to take off the iron mold, and when the gun body is still red-hot, remove the burrs on the gun body, and then after it is completely cooled, the mud core inside is removed, and the gun body is cast.

Lei Tuozi looked back at the iron mold again, there was almost no damage, and he could continue to cast it, and said with great joy: "Congratulations to Gongzi, this iron mold casting method is really feasible!" It can be said that the cost of one work and the profit of hundreds of jobs are not only saved time, but the cost of casting cannons is also greatly reduced! ”

Ning Yu naturally knew that this method would definitely work, so he was not too surprised, and said lightly: "Then rest assured, Master Lei, install the gun carriage fire door tomorrow, let's try how powerful it is." ”

Lei Tuozi nodded busily, and then instructed his craftsmen to start equipping the gun carriage, and everyone saw that the busy past few days had paid off, and when they thought of the rewards behind, they all mustered up their strength to do something well.

With the concerted efforts of everyone, but a day's effort, a sub-mother cannon was cast, and Ning Yu arranged for someone to pull this cannon to the northern foot of the mountain, where the area is empty and sparsely populated, and there will be no outsiders at ordinary times, which can be used as a test site.

Lei Tuozi stroked the cannon body, and said excitedly: "Childe, this iron mold casting cannon is really magical, because this casting mold is iron, it does not contain water, and there is no pores, plus the coal ash that Childe said, the entire cannon body is cast out as a whole, and the idle cannon will not explode, I think the amount of medicine can be increased to seventy percent this time!" ”

Ning Yu saw that the cannon had been cast, and his heart was also relieved, so he smiled and said: "Master Lei, before I came, I heard people often say that this Yunmeng's Lei Tuozi has always been a character who is not afraid of heaven and earth, why is the Master Lei I saw today empty?" ”

Lei Tuozi's face turned red, and he wrapped the braid at the back of his head around his neck, and spat fiercely at his hands.

"Add 10%!"