According to Li Zhiyun's plan, the arsenal is divided into two parts: the factory department and the production department, the factory department consists of a design department, a production department, a materials department, a general affairs department, etc., and the production department consists of a machine repair workshop, a casting and forging workshop, a firearms workshop, an ammunition workshop, a grenade workshop, and so on.

When Li Zhiyun left Chang'an last time, the construction of the arsenal had been 90 percent complete, and when he returned from Jinyang, not only had the building already been completed, but the equipment had been installed and formal production began.

The arsenal is divided into three parts: office area, production area and family area. At present, only one two-storey office building has been built in the office area, and in addition to the boiler room, five factories and three warehouses have been built in the production area. Although the factories are all brick and wood structures, they are all spacious and tall. Each factory building is 75 zhang long, 10 zhang wide, 1 zhang 5 feet high, and the doors and windows are opened on all four walls, and the ventilation and lighting are good. In order to save land, dozens of small three-story wooden buildings were built in the family area, each of which can accommodate six families.

On the first day after Li Zhiyun returned from Jinyang, he went to the arsenal to visit and inspect. The first thing he went to was of course the production workshop, and accompanied by a group of entourage, he first looked at the boiler room. The boiler room is a square building, eight feet long and eight feet wide, in which a boiler is installed. Due to the large amount of steam required by the arsenal, this boiler is also very large, and Li Zhiyun estimated that it was about the same as the four-ton boiler of later generations. The boiler, which was made by craftsmen based on drawings drawn by him, was very crude and rudimentary, and its complexity and precision could not be compared with the boilers of later generations, but the principle and function were not much different.

The most important thing about the boiler is to ensure safety, because there is no pressure gauge, it is impossible to know whether the vapor pressure in the vessel is too high, so as to avoid the boiler explosion. The craftsmen were clever enough to install a thin iron pipe to determine the pressure inside the vessel based on the force of the steam ejected and the amount of sound it sounded, similar to the pressure cookers of later generations.

The steam produced by the boiler is piped to a steam turbine in the adjacent building, which rotates and then transmits power to an iron rod five or six feet long. A wheel is installed every two or three feet on the iron rod, and various machine tools are installed on both sides, and the power on the wheels is transmitted to the machine tool through the belt transmission device, so as to drive the machine tool to operate.

Since there is no rubber, the belt is woven from coarse linen, which is very wear-resistant, so the wear rate is very high. As for the machine tools, they are all made by craftsmen, there are lathes, drilling machines and milling machines, which are very rudimentary, and most of the parts are made of wood, which is barely usable. Among them, the lathe is the most important, and it depends on it to drill the barrel and the rifling wire.

The biggest disadvantage of relying on steam for power is that once the turbine rotates and outputs power, all machine tools must follow the operation. Li Zhiyun has already sent someone to find magnetite, once he finds the magnet, and then draws the copper into wires, with magnets and copper wires, he can make a generator and use firepower. With electricity, the next step is to electrify the arsenal.

Li Zhiyun came to another factory, this factory has many wooden workbenches, on which are installed tiger tables, and grinders and other things, and craftsmen have also made files, vices, calipers and other tools. Of course, there are many machines here, but they are all manual.

Some craftsmen are working. He walked over to a lathe and watched, which was powered by a three-foot-diameter wooden wheel with iron weighted wheels on the outside, which were rotated by one man to drive the lathe wheel to rotate. The accompanying craftsman explained, "It takes a lot of effort to spin this wheel, and on average one person needs to be replaced every hour. ”

He came to the casting and forging workshop, where there were seven or eight crucibles, and there were many models on the ground, including stone, clay and sand. Ancient casting methods include stone casting; Tao fan casting, that is, clay casting; Iron fan casting, that is, metal mold casting; In addition, there are lost wax casting and sand casting.

He saw a craftsman use iron tongs to bring the molten iron from the crucible and pour it into the sand mold, which made the sand mold hiss and emit a trace of blue smoke, and when the molten iron cooled, the casting was formed. The other half of the workshop was like a large blacksmith's shop, with several hearths, anvils, hammers, etc. Several craftsmen are forging iron pieces in a "ding-ding-ding" way, which is forging them. Since there is no electric welding, all weapon parts are molded at once, either cast, or forged, and then polished, and finally baked blue.

To make modern weapons, in addition to craftsmen and equipment, it is necessary to have materials, the most important of which is steel. Since the Han Dynasty, the ancients have learned to make steel, mainly including the carburizing method of block iron, the method of frying steel, the method of filling steel, the method of making steel, the method of frying iron carburizing, etc., among which the frying process can generally refine forged steel and wrought iron, and the steel filling process mainly produces bladed steel with high carbon content.

Although the quality of steel at this time was far inferior to the gun steel used in later generations, Li Zhiyun now has limited funds, and it is impossible to open a steelmaking plant to make good steel, so he can only make do with it. Fortunately, he did not pursue the quality of the weapons he produced, as long as they could reach the level of World War I, he was satisfied.

Then, Li Zhiyun came to the gun workshop, where many craftsmen were busy making guns. Firearms are generally divided into two types, one is a smoothbore gun, commonly known as a bird gun, also known as a shotgun. The other is a rifled gun, also called a belly gun.

Li Zhiyun planned to produce both kinds of guns, the bird gun is composed of a barrel, a powder pool, a bolt, a front sight, a gun handle, etc., the bolt adopts a tunnel type, that is, a piece of flint is clamped on the jaws of the hammer, and a blow anvil is provided on the side of the fire hole, and when shooting, the trigger is pulled, and under the action of the spring, the flint is hit heavily on the anvil by the fire door, and a spark emerges, igniting the gunpowder and firing.

The principle is to make the bolt rotate to one side to unlock the lock, and then pull the bolt backward to compress the firing needle spring and the re-entry spring, and exit the cartridge case, and finally push the bolt forward by the re-entry spring, push the bullet into the chamber and make the bolt rotate to the other side to complete the locking. During World War II, Germany's Spear 98 and Japan's 38 Dagai adopted this kind of manual bolt.

Although Li Zhiyun drew drawings of various weapons, they were only schematic diagrams, and not every part was drawn. Because, he didn't know what some parts looked like, and as for the specific size of each part, he had no way of knowing. Therefore, he set up a design section in the factory department, specializing in the design of weapons. The dozen or so people in the design department are all former ministers of the Sui Dynasty, and they used to be in charge of river repair projects, and they are very expert in surveying and drawing. After the fall of the Great Sui, the world was in chaos, there were wars everywhere, and the imperial court didn't need them to repair the river, so they lost their jobs. Li Zhiyun brought them in and asked them to draw drawings. He plans to wait for the reunification of the Tang Dynasty before letting these people go back to their old jobs, which can be regarded as retaining a group of talents for the country.

Based on the principle of the weapon he provided, the people of the design department worked with the craftsmen to make each part, and after repeated trials, the dimensions were fixed and drawn into drawings.

Finally, Li Zhiyun came to the explosives workshop. The explosives workshop produces explosives and grenades. At the beginning, after Li Zhiyun left the "Women's Army", those craftsmen continued to study nitroglycerin explosives, constantly carried out experiments, improved the ratio of raw materials, and made the explosives more and more powerful.

In addition to the production of black explosives and nitroglycerin explosives, the more powerful chemical explosives are also produced here. The most important raw material for the production of chemical explosives is sulfuric acid, the ancients would produce sulfuric acid for a long time, and ancient Taoist priests used sulfuric acid to alchemy. The oldest method of producing sulfuric acid is to use green alum as raw material and calcinate it in a distillation kettle to produce sulfuric acid. Therefore, the ancients called sulfuric acid "alum oil." Li Zhiyun saw that there were five or six clay jars used for pickles in the corner of the workshop, which were used to hold sulfuric acid.

As for the grenades, they were made of wooden-handled grenades, the body of which was forged from wrought iron, and the gang was equipped with black powder as a detonator.

In the months since Li Zhiyun left Chang'an, the arsenal has produced samples of various weapons. As soon as the wound on his buttocks healed, he took someone for an experiment. However, he was very disappointed that mortars and grenadiers could not shoot the shells at all, and he did not know whether it was due to the shells or other reasons. The incoming rifle was also faulty and could not shoot normally. Only the Bird Gun and the Grenade met his expectations, and the craftsmanship of these two weapons was relatively simple, so satisfactory results were achieved.

It was only at this time that Li Zhiyun realized that although the scale of his arsenal was not small, the machinery and technology were too backward, only equivalent to the level of family workshops in later generations, and it was unrealistic to want to produce weapons with more complex processes now, and only by starting with the production of the oldest firearms, step by step, while improving the machines, while improving the technology, and then gradually transitioning to the production of modern weapons.

As a result, he halted the production of rifles, grenadiers, and mortars, and kept only three research teams to produce them in small batches after they had developed qualified samples.

In addition to producing bird guns and grenades, Li Zhiyun also had the arsenal produce redcoat cannons. This kind of cannon is composed of the body barrel, medicine room, cannon tail and other parts, the barrel is an iron smoothbore, the ammunition is preloaded, it can fire stone bullets, iron bullets and explosive bombs, etc., it is the same as the bird gun, the process is relatively simple, although it is very backward compared with modern artillery, but it is used to deal with the army that does not have any firearms and is only equipped with cold weapons, it is more than enough.