The outer wall of the barrel is temporarily ready, and now it is necessary to make the inner hole mold of the pipe. Pen | fun | pavilion www. ｂｉｑｕｇｅ。 ｉｎｆｏ

First of all, he asked people to take the wax liquid and pour it into the pipe, and then slowly pull it out after the wax is dry, wash the pipe and fill it again, and then take out the mold again, several times in a row, the purpose of this is to get the accurate inner hole size of the pipe.

After making the wax mold of the inner hole of the pipe, Zhao Guohua ordered the jewelers to make an identical clay mold with refractory clay according to the size of the wax mold of the inner hole of the pipe, and then put it aside for later use.

After the two molds are ready, they are lifted to the iron-making place, they are buried in the casting sand pit, and when the iron in the iron-making furnace is turned into molten iron, the molten iron is poured into the sand shell, and finally the molten iron left in the sand mold is cooled, and it becomes a gun pipe casting.

After the molten iron cooled and solidified, the firearms craftsman Du Decai picked up the hot pipe casting from the casting sand pit, looked at it carefully for a while, and then exclaimed in surprise: "It's finished!" It's done! ”

Wei Sanxi and Yang Hong also hurriedly snatched the gun tube casting, their eyes radiated a scorching light, and they looked at it carefully over and over again in ecstasy, as if they were looking at a rare treasure.

Objectively speaking, the appearance of this pipe casting is not very smooth, there are several fine holes in some places, and the inner wall is not very smooth. However, in the eyes of the three of them, this is already perfect, in the past, they wanted to make such a pipe, without dozens of people, it was impossible not to spend three days, but now according to this wax mold casting method, it is not much problem to make forty or fifty pipes in three days.

And as the craftsmen become familiar with the technology, the quality of the cast guns will get better and better.

Looking at it, the three of them looked at each other and nodded to each other, "Poof...... Puff ...... ......"Firearms craftsmen Du Decai, Wei Sanxi, and Yang Hong knelt down in front of Zhao Guohua and kowtowed respectfully......

"Why are the three masters?" Seeing that the three of them kowtowed to him for some reason, Zhao Guohua was startled, and he hurriedly reached out to pull,

The three of them kowtowed and said excitedly: "Childe will teach this technique to me, and I will worship Childe as a teacher." ”

In ancient times, no one else dared to use the technology without the consent of the owner. The wax casting method taught by Zhao Guohua has surpassed the technology of the Ming Dynasty, and these three people know the great value of this technology, so they are willing to worship Zhao Guohua without hesitation.

As soon as he heard that this was the case, Zhao Guohua understood, and said in his heart: "These three people have vision, no wonder they can be masters in the Ordnance Bureau, indeed, if this technology is done well, it will be enough for their children and grandchildren to eat for a few lifetimes." Thinking of this, he smiled and said, "You three get up, I agree with you to use this technique of mine, but there is one condition." ”

"What conditions? Childe, please say, the three of us and the others will all obey. As he spoke, the three of them stood up, beaming with joy and respect.

Glancing at the three of them solemnly, Zhao Guohua said solemnly: "That's confidentiality, only the three of you have seen this technology throughout the whole process, and other people don't know, if this technology appears in other people in the future, especially Tartar, then you know the consequences." ”

Zhao Guohua understood that if this technology was transmitted to the Qing army, it would speed up the speed at which they would cast cannons, which would not be a good thing for the Ming Dynasty.

Hearing this, not only were the three of them scared and covered in cold sweat, Bi Maokang also nodded frequently, he also said something with a strong voice, and even the words of the three clans were said, and the three of them were even scared to lie on the ground and kowtow and swear.

Pulling the three of them up from the ground, the group left the ironworks and returned to the wax mold workshop.

After paying wages and rewards, dismissing the jewelers, and under the orders of Bi Maokang and Wang Gui, the ambassador of the Ordnance Bureau, everyone began to make the 2,000 Lu Mi guns for Zhao Guohua. Due to the casting method of the gun tube, the gun tube is much faster, but Zhao Guohua found another problem. That is, there is always trachoma on the surface of the cast gun.

"Childe, the trachoma on this pipe, no matter what we do, we can't get rid of it." Wei Sanxi said cautiously

Indeed, in the past few days, no matter how slow or fast they poured, the trachoma in the gun tube could not be eliminated, and there was no way, and the three of them could only ask Zhao Guohua for help.

Looking at the trachoma on the twenty or thirty guns cast, Zhao Guohua was puzzled, and later, he ordered the craftsmen to smash the pipes with sledgehammers and carefully look at the port at the trachoma.

After studying for several days and looking at many places, he finally understood that it was because the impurities in the iron had not been removed. According to the original method, the iron used to make the pipe should be forged repeatedly to remove impurities. Now the casting method is adopted, which is almost fast, but the impurities are left in the molten iron, and after the casting is cooled, trachoma appears in the place where there are many impurities.

After figuring out the reason, Zhao Guohua remembered the fact that limestone was added to the local steelmaking process in the small steelmaking mills in some counties and districts in later generations, and this method was mainly used for slag making. Its purpose is to make the impurities in the molten iron adhere to the limestone to form oxide slag, which is easy to clean and conducive to the purity of the molten iron. Limestone is not a raw material for steelmaking, it is an auxiliary material, because there are too many impurities such as carbon, sulfur and phosphorus in the molten iron, and adding limestone can better remove the impurities in the molten iron.

"Master Du, if you add some quicklime to make iron, it may help to make good iron." Zhao Guohua said.

Du Decai asked puzzledly: "What is the use of iron-making and quicklime?" ”

"Master Du, don't ask too much, just re-smelt the furnace iron according to Guohua's requirements, I believe that the method he said can solve the problem of trachoma." Bi Maokang said without doubt.

"Yes, the villain will go to the ironmaking workshop right away." Du Decai bowed down and said

After several iron-making tests, the right ratio of molten iron to limestone was found. The molten iron smelted by the new iron-making method was finally cast without trachoma.

In the prison, a few death row prisoners who had killed people and oversold goods were put on shackles, and under the supervision and coercion of officers and soldiers, the death row prisoners experimented with a new method of casting a cannon made of a Lumi gun. The ten Lumi guns were all tested fifty times in turn, and except for one that blew up the chamber for the thirtieth time, everything else was fine.

After analyzing and researching, it was found that the blow up was due to the excessive gunpowder.

After finding the reason, everyone no longer had any doubts about the cast guns. The production speed of the 2,000-stroke Lu Mi Gong has also been advanced from the original fastest three months to 20 days, and Zhao Guohua has added another 1,000 strokes, for a total of 3,000 strokes.

"Guohua, you see, this is a kind of impact fire gun that I just developed not long ago, when the gun is fired, the head of the hand buckle machine is pressed down, and the head of the dragon and the flint are hit hard under the action of the spring, and sparks emerge, igniting the gunpowder by the fire door to fire. In this way, not only did they overcome the difficulties caused by wind and rain in shooting, but they also did not need to press the faucet with their hands, so that the aiming was more accurate and they could be fired at any time. The gun is not afraid of wind and rain and does not require prior arquebus ignition, and the firing speed and accuracy are greatly improved. Bi Maokang said, handing an improved firearm to Zhao Guohua.

Curiously took it, observed it carefully, and said with a smile: "Uncle, how about I try a few shots?" ”

"It's just for you to try, after trying it, you can see if you can improve it, after all, the fire guns you have seen in Huaxia Kingdom are not comparable to this simple fire guns." Bi Maokang said.

Loaded with gunpowder and projectiles, "Smack." A gunshot rang out, Zhao Guohua fired a shot, and then loaded the gunpowder and projectiles, "Smack." "One more shot, another shot...... After a few shots, Zhao Guohua stopped shooting.

"Guohua, how is this firecracker?" Bi Maokang asked.

Glancing at him, Zhao Guohua said: "Uncle, this musket is much better than the arquebus, the arquebus needs to drag a long lit arquebus when fighting, it can't be used in rainy days, and the light of the arquebus at night is easy to expose the shooter." But the gun has a big drawback, that is, it is very laborious for the soldier to press down with the faucet of the hand buckle machine. So I think we should change the ignition method. ”

"Change the ignition method? How to change? Bi Maokang looked at the percussive firearm and asked suspiciously.

"You let me think about it." Zhao Guohua said.

Looking at him, Bi Maokang said: "You take it back and study it carefully, don't be in a hurry in the next day or two." ”

Taking the percussive firearm back, Zhao Guohua studied it carefully, thought about it, and couldn't think of how to improve it for a while, so he got used to wanting to light a cigarette and smoke, and reached out to touch his chest, only to find that he was wearing Ming Dynasty clothes, and there were no pockets on his chest.

With a self-deprecating smile, he retracted his hand, and then a flash of inspiration flashed in his mind: "Smoke - lighter"

"Oh! Pregnant! He rushed out with a ramming firearm to find Bi Maokang......

At the suggestion of Zhao Guohua, Bi Maokang changed the impact ignition method to friction ignition, that is, the lower end of the faucet of the plate machine was changed to the style of gear, and the thick spring was changed to a thinner spring. (that is, the ignition method of flint lighters in later generations), flint is not the original hard flint, but the flint surface is coated with a red phosphorus layer, which is easier to ignite the ignition rope.

"Guohua, your improvement is much more ingenious than my method." Looking at the new ignition method of the fire gun, Bi Maokang praised repeatedly.

Bi Maokang tried it more than a dozen times, and was very satisfied with the shooting effect, and he said with a smile: "This improvement, the soldiers use this gun, and the effect is much better." Guohua, you deserve to have come back from overseas Huaxia, you are really talented! ”

"Uncle has won the prize, this gun is still too much worse than the firecracker of Huaxia Kingdom."