Yongli Ming Dynasty

Chapter 239 Iron Mold
Zhu Lang stood in front of the wooden platform, looking at the black cannon in front of him, frowning slightly, and said

"That means that this batch of artillery will only have 30 guns in the end."

Yang Huiqi saw His Majesty the Regent frowning, and knew that His Majesty the Regent was unhappy, so he quickly spoke up.

"This time, the Heavy Artillery Division's personnel arrived one after another, so the number of clay molds made was small. Now that we have all the manpower, we should be able to make more molds when we open the molds again."

"However, it takes at least one or two months, or at most two or three months, for the clay mold to dry in the shade. If the court needs to cast a large number of cannons, I am afraid we will have to increase manpower and make more cannon molds in order to increase output."

This is the biggest disadvantage of clay mold casting. The clay mold must be completely dried before casting. Before the clay mold is completely dry, everyone can only wait on the sidelines.

After the dried clay molds were cast into cannons, they would be broken into pieces to remove the cannons, and could not be reused.
This one-size-fits-all approach is not only inefficient, but also makes it difficult to unify regulations.
Even if the same batch of 3,000-jin heavy cannons were produced, due to differences in the production of the cannon molds, the cast iron cannons were large or small, light or heavy, and basically could not be of uniform size.
Zhu Lang had previously only instructed Chen Zizhuang and others to recruit blacksmiths to set up the Arms Bureau, and then led his troops to Fujian, but he did not have time to manage the production of the Arms Bureau.

Now that they have time, they naturally need to improve the cannon casting process and increase the production speed of the cannon.
Now the four prefectures in southern Zhejiang and the passes in Fujian Province are located on the front line and may face the attack of the Qing army at any time. These places are waiting for the use of artillery.
If a dozen heavy artillery pieces could be placed in border cities like Jinhua and Wenzhou, the Ming army would be able to easily defend them even if the Qing army attacked with all its might from the south of the Yangtze River.
Heavy artillery is powerful for attacking a city, but it is even more terrifying for defending a city. With the support of the city wall, the heavy artillery on the top of the city can continuously bombard the attacking party.

With the terrifying destructive power of these heavy artillery, the morale of the soldiers attacking the city would probably have collapsed before they even reached the foot of the city wall.

Zhu Lang glanced at the broken clay model on the ground and said

“Since clay molds take a long time to dry in the shade, why not use iron to make the molds?”

Yang Huiqi was stunned when he heard this and said

"How can iron be used to make a mold? If it is made of iron, how can we break the mold and take out the cannon after the casting is completed?"

Whether it is the lost wax method or the mud mold method, these two mainstream methods of casting cannons at this time are to break the mud mold after pouring and take out the cannon body.

If the mold was made entirely of iron, Yang Huiqi could not imagine how to take the cannon out of an iron mold.
Zhu Lang glanced at Yang Huiqi, who looked confused, and said directly

"The entire cannon mold is cast in sections, made into a tile-like shape, and then joined together like mortise and tenon joints to form a complete cannon mold."

"After pouring, wait for the cannon shape to solidify, and then immediately remove the cannon mold in sections. Is this feasible?"

What Zhu Lang said was actually the iron mold casting method of later generations. The principles of the iron mold casting method and the mud mold casting method are basically the same.
The only difference is that the disposable clay mold is turned into a reusable iron mold.

This is not a surprising technological breakthrough, but just a slight change in the original clay modeling process.
But it took nearly two hundred years for this change to be improved in later generations.
The advantage of the iron mold casting method is that it is fast. Compared with the clay mold method, which takes two or three months, the iron mold method can continuously cast cannons at a very fast speed because there is no need to wait for the clay mold to dry in the shade and the iron mold can be reused at any time.
With an iron mold, a dozen craftsmen can cast four or five cannons in a month. Compared with the clay mold method, the casting speed of the two is simply incomparable.
The biggest advantage of the Ming army over the Qing army was firearms. After improving the iron mold casting method, the Ming court was able to crush the Qing court in firearms.
With the same number of craftsmen, the Qing army could produce hundreds of cannons a year using the clay mold method, while the Ming army could produce thousands or even tens of thousands of cannons using the iron mold method, giving the Qing army an absolute firepower advantage.
Of course, the iron mold method is not without its disadvantages. Although the mud mold method is slow to cast, the good heat resistance of the mud mold allows the molten iron to cool slowly, generating tough gray iron. Such artillery is often more durable.
The iron mold method uses an iron mold, and the molten iron in the iron mold will cool quickly after casting, producing a large amount of hard and brittle white cast iron.
Such artillery is very easy to explode during use. In order to solve this problem, the only way is to continuously thicken the wall of the artillery to solve the problem of poor barrel material.

The same cannon that uses a 10-jin iron bullet may only weigh 2,000 to 3,000 jin if it is replaced with a clay-cast iron cannon. However, in order to ensure that it will not explode, the weight of the cannon cast in an iron mold is often increased to 5,000 to 6,000 jin, and even 7,000 to 8,000 jin is not uncommon.

Cannons weighing two or three thousand jin are already inconvenient to transport, and iron cannons weighing five or six thousand jin are obviously not worth transporting.

But this also cannot cover up the advantages of the iron mold method. As long as there are enough craftsmen, hundreds or even thousands of cannons can be cast in a short period of time. This alone is enough to cover up all the shortcomings.

Yang Huiqi frowned and thought for a while, but then his eyes became brighter and brighter, and finally he couldn't help but speak

"It should be possible to use a combined mold and take the mold in sections... No, it must be possible."

"If the cannon mold problem is solved, then we can smelt pig iron at any time and start the furnace to cast cannons at any time. The output will surely increase by dozens or even hundreds of times, and we won't have to spend money every time to make time-consuming and laborious clay molds."

"Your Highness is truly a genius. How could we not have thought of such a brilliant idea? If the clay mold doesn't work, why not use an iron one? This is a great idea, a real great idea!"

Yang Huiqi's face flushed, and he even danced with joy for a moment. If His Royal Highness the Regent was not still beside him, Yang Huiqi could hardly resist trying to make an iron mold immediately to see how effective this iron mold method was.

Chen Zhu and Zeng Cheng, two artillerymen standing by, were also excited when they heard this and were eager to try.
Zhu Lang looked at the three people who were excited, and he knew in his heart that this iron mold method should not be difficult for these master craftsmen.

In fact, it is really not difficult at all. It is just a matter of a layer of paper. Once it is broken, there is almost no difficulty at all.
Zhu Lang was alert when he thought of this. Since there was no difficulty on their side, it meant that there was no difficulty on the Qing court side either.

The Qing Dynasty occupied the north and south of the Yangtze River, and had more than enough craftsmen resources at its disposal.

Zhu Lang looked at Yang Huiqi and the other two who were still excited, and said in a deep voice
"The iron mold method is a top secret of the imperial court and must not be peeped at by outsiders. Yang Huiqi, you three will select 500 blacksmiths with families from the Military Equipment Department. After the iron mold is successfully manufactured, you will select another site to cast cannons using the iron mold method."

"When the Iron Mold Artillery Factory was making cannons, the Jinyifu was in charge of the casting and no outsiders were allowed to peek in."

"Li Chengzhi, you will send people from the Jinyifu to Foshan later to bring the families of these 500 blacksmiths to Guangzhou, and give them land in a place in the suburbs, so that they can live together." Yang Huiqi and others were stunned when they heard this, and their excitement about discovering the new technology was immediately extinguished.
How could they not understand that His Royal Highness the Regent was using his family to hold the craftsmen hostage to prevent the loss of the iron mold casting cannon technology? As the heads of the three departments, they would probably have to accept the same treatment.
Zhu Lang glanced at the three panicked craftsmen and spoke again.

"Master Yang, don't be alarmed. The iron mold method can increase the speed of casting cannons by a hundred times, but it is too easy to copy. In order to prevent the Qing invaders from discovering this technique, it needs to be strictly managed."

"The court will be at war constantly in the future, so it is time to recruit people. The treatment promised by the court before will not change. You just need to rest assured and cast cannons."

"I understand, we will do our best to forge a good cannon for your highness."

The three craftsmen in charge all had cold sweats on their heads. They kept nodding their heads, but they were becoming more and more uneasy in their hearts. They didn't know whether it would be a blessing or a curse for them to suddenly hear about the iron mold method.
Zhu Lang ignored the three craftsmen's thoughts. After arranging the confidentiality of the iron mold method, he went to the camp artillery site to check.

The Battalion Artillery Department was specialized in replicating and casting Portuguese cannons weighing 300 to 500 kilograms. These cannons often had to be moved with the army, so they could not be made too heavy.
There is no need to say much about these light artillery. Compared with heavy artillery weighing thousands of pounds, these light artillery are much simpler to build.

And because these battalion guns were frequently used, these light guns were all cast in copper, which made casting easier for the battalion gun division.

Copper has a low melting point, and its ductility and toughness far exceed that of iron, making it the best material for casting cannons in this era.
Copper is good for casting cannons, except for one thing: it is too expensive. At that time, the Ming Dynasty used copper coins, so there was no difference between casting cannons with copper and casting cannons with coins.
The court recruited blacksmiths to forge their own cannons. Compared with buying them from Haojing, the price was much lower than before. However, the price of a copper cannon, including the cost of materials and the salary of the craftsmen, was still as high as 20 taels of silver.

But this is impossible. Casting with iron is cheaper, but these battalion artillery pieces are often used by the army.
The probability of an iron cannon exploding is too high. If this continues, the army may become like the Chongzhen Emperor, preferring swords, guns, bows and arrows to cannons.

Zhu Lang looked around the camp artillery department and watched the process of casting the camp cannon again. This was not much different from the previous heavy artillery, except that the molten iron was replaced with molten copper.
Zhu Lang encouraged the head of the Camp Artillery Division and a group of craftsmen, and then went to the Firearm Division's workshop.

The artillery department of the heavy artillery camp was mostly in the open air, while the craftsmen of the firearms department were in blacksmith workshops. At this time, a group of blacksmiths were swinging hammers and forging iron bars. The workshop was filled with the sound of clanging.
The structure of the fire gun of this era is extremely simple, basically a barrel, a handle and a gunpowder pool
When using a musket, the bullet is inserted into the barrel, the match ignites the gunpowder in the gunpowder pool, and the gunpowder explodes to generate thrust, which pushes the bullet to fire. The principle is basically the same as that of fireworks.

The most important part of making a fire gun is the barrel. In order to withstand the impact of the gunpowder explosion, the barrel is made of extremely tough wrought iron.
When making a gun barrel, a round iron rod is used as the axis. The forged long iron block is heated and attached to the iron rod, and then the barrel is made into a cylindrical shape around the iron rod.
The barrel made in this way will have seams at the interface, which obviously cannot be used directly. The solution is to make a larger outer barrel and wrap the seams of the inner barrel inside the outer barrel. This is the so-called double-layer composite barrel.

Although the name of the Firearms Division is Firearms, in fact, the weapons made in the Firearms Division are not matchlock rifles, but flintlock rifles.

At the Firearms Division test site, a Jinyiwei soldier was holding a black flintlock rifle. The place where the matchlock was originally clamped was now replaced by a small square flint.

The soldier suddenly pulled the trigger, and the flint was pushed down and hit the flint plate under the action of the machine frame. The cover of the gunpowder pool below was moved away, and a bunch of sparks fell into the gunpowder pool. With a bang, the bullet flew out from the muzzle.
Zeng Cheng, the head of the Fire Gun Division, heaved a sigh of relief when he saw the flintlock rifle fired successfully.
Even though this flintlock rifle was carefully forged, there was still a certain chance that it would not fire in one go. Zeng Cheng felt relieved that he had not failed in front of His Highness this time.

The flintlock rifle was not a top-secret weapon that had never been seen before. Europe had developed the matchlock rifle decades ago. With the arrival of the Portuguese and other foreigners, the Ming court had already known about this type of weapon. The Ming court called this type of rifle that did not require a matchlock a self-generating fire gun.
Zeng Cheng had worked as a craftsman in the Haojing Cannon Factory, casting cannons and forging guns. He had seen this kind of self-propelled muskets in the hands of the Hongyi nobles in Haojing. Therefore, after he had enough manpower, he successfully imitated the flintlock rifle.
But when Zhu Lang asked about it, he frowned. In the past two months, the Fire Gun Department had only produced more than 600 flintlock rifles.
Now, each of the three divisions of the Military Equipment Bureau has 1,000 craftsmen. That means that more than 1,000 craftsmen can only make more than 300 flintlock rifles a month. On average, it takes three craftsmen a month to make one flintlock rifle.
Zeng Cheng saw His Royal Highness frowning, and his heart tightened. He quickly reported
"The gunsmiths in the Firearms Department were not originally professional gunsmiths, so they were not very familiar with the art of making gun barrels."

"During the past two months, I have been giving instructions every day, and all the blacksmiths in the company have started to get the hang of it. In the future, the speed will definitely increase. I guarantee that the monthly output will double in the future."

"The structure of this self-generating musket is actually not much different from that of a matchlock gun. The only difference is that this self-generating musket needs a reed to trigger the mechanism, which drives the flint to strike and ignite."

"This reed must be made of extremely fine and tough wrought iron before it can be used. The reason why the Fire Gun Company is inefficient is that it is difficult to make this reed, which slows down the production speed."

Zhu Lang frowned slightly when he heard this. He knew a little about how to cast a cannon with an iron mold, but as for how to make a reed, he really didn't know.

After some inquiries, Zhu Lang discovered that the craftsmen in the Fire Gun Division basically worked independently. From forging the gun barrel to making the reed, to the machine handle, all were done by one person.

Zhu Lang's mind turned, and he also spoke

"Since reeds are difficult to make, we can select experienced craftsmen from the company and have them specialize in making reeds."

"The same goes for the gun barrel, mechanism, and handle. One group of people makes the barrel, another group makes the reed, and finally someone else makes the whole gun."

"Letting dedicated people do dedicated work will help them master their skills over time and improve the forging speed. What do you think?"

This is actually the assembly line production method of the past, which divides the process into various links and assigns specific people to be responsible for a certain process. In this way, over time, practice makes perfect and production efficiency can be improved.

For example, if a blacksmith is good at forging reeds, he should continue to make reeds and improve the process.
Instead of having him make a reed and then make the barrel and the frame, this way, enough reeds can be produced at the fastest speed.

Zeng Cheng was hesitant when he heard this. The atmosphere at that time was different from that in later times. In this era, every skill was a means to make a living.
Craftsmen of this era often worked alone and had to master a skill from beginning to end. Only in this way could they be considered to have mastered the ability to make a living. The so-called division of labor and cooperative production was extremely unfamiliar to these craftsmen.
In Zengcheng's workshop, firearms were basically made by each craftsman individually, but this kind of division of labor and cooperation method had never been tried before.

However, His Royal Highness the Regent had already spoken, and it sounded quite reasonable, so Zeng Cheng did not dare to refuse outright, so he had to accept it first.

Zhu Lang inspected the three divisions of the Military Equipment Bureau and found that various guns and cannons were already in production. He was quite satisfied. In just two or three months, he was able to recruit so many blacksmiths to produce guns and cannons. The speed was not slow.
This is also thanks to the fact that it is in Guangdong Province, where commerce is developed. If it were in other inland provinces, it would take a long time just to gather so many skilled craftsmen.
It was past noon. Zhu Lang and the three chiefs had finished lunch and were preparing to watch how the heavy artillery department and others tested the gunpowder in the afternoon.
However, the news from Jinyifu forced Zhu Lang to temporarily stop his inspection of the Military Equipment Bureau and return to the Governor's Office in advance.
(End of this chapter)