With the 'support' of the nobles, a pale man went to the Army Lecture Hall, which was the cradle of future officers in the Ming Dynasty.

Zhu Shun temporarily put down the micro-control of the army's martial arts hall, changed to macro-control, and left Xishan to go to the Daming Arms Company.

The bolt to ensure the airtightness of the breech-loading rifled gun was still not invented, but Zhao Doumi had an improvement in another direction, which could also make the Manchus and thieves suffer a big loss.

Increases the lifespan of the Hongyi Cannon.

The service life of a cast iron cannon is about 550 rounds, and although the copper smoothbore gun is heavier than a cast iron gun, the service life is much longer, about 900 rounds.

The Manchus and the thieves had no concept of service life, but after so many years of fighting, it can basically be estimated that the Hongyi cannon of the Ming Dynasty can bombard for a few days.

First of all, by bribing some generals under the command of the army leader, we can understand what kind of artillery it is, and judge the number of days according to the texture of the artillery, as long as it exceeds this number of days, it is a fighter plane for the Manchus and thieves to launch a large-scale attack.

If the service life of the cast iron cannon is increased to 900 rounds, or even more than 1,000 rounds, wait until the Manchus and thieves withdraw the cannon fodder and dispatch the elite to start a large-scale attack.

In the face of artillery bombardment everywhere, the expressions on the faces of the Manchus and the thieves must have been wonderful.

The floor of the cannon shop was hardened and paved with a thick layer of concrete, and a gear-driven transmission system was installed on the top of the empty workshop.

Powered by a steam engine, it drives the crane at the top of the cannon casting workshop, lifts the mud mold, and transports away the heavy cannon that has been manufactured.

There is also an iron melting furnace in the cannon casting workshop, which sticks out of the chimney outside the workshop, billowing black smoke.

In order to dissipate heat, the casting workshop left a large window on the surrounding walls, which were emitting white gas.

Zhu Shun walked along a cement road into the cannon casting workshop, and in the colder late autumn, there was a heat wave in his face, and the air he breathed carried a scorching smell of iron juice.

It's already late autumn, and all the cannon casters inside are wearing cardigans, so thinly dressed, their heads are still covered with sweat.

Gunsmiths are closely controlled craftsmen in Daming, and there are not many gunsmiths in Daming Arms Company, but when Zhu Shun walked into the foundry, he saw a large increase in the number of gunsmiths in several cannon casting workshops.

Zhu Shun looked at Zhao Doumi, the fourth disciple who was standing next to him in a long robe, and asked, "Why are there more skilled workers in the cannon casting workshop than before?" Could it be a gunsmith recruited from Foshan? ”

Foshan, one of the four gatherings, the best-selling bulk goods are bronze, giving birth to many skilled coppersmiths who have been passed down from generation to generation, and the imperial court has set up a cannon factory here.

However, the imperial court's dominance over the two Guangxi provinces was obviously inferior to that of the governors of Henan and Zhejiang, and the cannon foundry set up in Foshan in the early years was basically eaten by the yayads and asked for a deficit.

There was no choice but to entrust it to some local squires to cast copper cannons, and there were a lot of private artillery factories.

So Zhu Shun asked if it was a gunsmith invited from Foshan in Liangguang, otherwise it would be difficult to find so many gunsmiths.

Zhao Doumi still looked generous and neither humble nor arrogant, but he was much more humble in front of his teacher: "This is thanks to the Fan family's great shopkeeper of medicinal materials, who gave it to nearly ninety of our skilled gunsmiths." ”

Zhu Shun later heard from Wang Chengen that the shopkeeper of medicinal materials for the workers' ticket numbers was actually a big spy of the Manchu Qing Dynasty and a big spy who had given Dongchang a headache for a long time, but he didn't expect it to be planted in the hands of the industrial faction.

Zhu Shun came over today mainly to cast cannons, nodded, and said calmly: "Let's start introducing the cannon casting method." ”

Zhao Doumi didn't walk to the molten iron furnace, but first walked to the side of the skilled worker who was making clay molds, sighed and said: "Master, the cannon casting technique of the Ming Dynasty is still relatively backward compared to the Western cannon casting technique. ”

After saying this, he called a gunsmith and a few apprentices to start demonstrating the Ming Dynasty's cannon casting method.

The casting technique of the Ming Dynasty is divided into four steps, using water and mud to make a clay mold, casting Fan Jin, and combining the bamboo shoots layer by layer.

Clay is not something that can be used with any kind of mud, but clay, which is much harder than ordinary clay and will not deform after drying.

The head of the gunsmith usually asks the apprentices to use water and clay mud, and today the industrial Hou Zhu Shun is here, rolling up his sleeves and going into battle in person.

Use water and a large amount of clay mud and put it aside for later use.

The head of the gunsmith deliberately wiped the sweat on his face, showing his diligence and responsibility, and peeked at the industrial hou Zhu Shun, and saw that the industrial hou nodded.

The artilleryman was overjoyed, and he was more motivated to take the next step and make a clay mold.

The artillery demonstrated this time is just a tiger squat cannon of dozens of catties, not a siege Hongyi cannon of more than 1,000 catties, and it is relatively easy to manufacture without the use of a crane.

After the two apprentices reconciled the mud, they brought a standardized wax model, which was carved from a wax block into a tiger squat cannon, and the caliber, body tube, and bore wall were all standardized.

Zhu Shun took a closer look, it was actually a tiger squat cannon carved from a wax block, carved according to a 1:1 ratio, which was the same size as the tiger squat cannon to be cast.

After the wax model was moved, the clay mold was made, and the gunsmith pasted a layer of clay mud on the outside of the wax model, and the barrel of the wax model tiger squat cannon was also filled with clay mud.

The wax mold is wrapped in clay and mud, leaving an inlet at the end for pouring iron or copper water.

After the clay mold is made, it must be thoroughly dried from the inside to the outside before it can be cast, otherwise the moisture in the clay mold will form a honeycomb-shaped hole in the gun chamber when it encounters the metal solution, and it is easy to explode when the gun is cast.

There is no trick in the shade drying of the mud mold, it can only be placed on the flat ground to dry naturally, even if it is baked with charcoal, there will be a lot of moisture inside.

The head of the gunsmith asked several apprentices to bring a dry clay mold, and introduced nervously and excitedly: "Generally speaking, it takes at least a month to dry the mud mold, and this is still on a sunny day. ”

"If it's rainy, or it's cold now, it's going to be at least two or three months."

The head of the gunsmith didn't dare to look directly at the industrial Hou Zhu Shun, stumbling after saying the introduction of the clay mold yin drying time, secretly glanced at the industrial Hou Zhu Shun, and found that the industrial Hou nodded again, and he was almost unable to close his mouth with joy.

The apprentices brought a mud mold that had been dried in the shade and began to process the clay mold to complete the last step.