In Zhao Hongrun's memory, if a "modern machine tool" were used to cast the candle-making machine, it might only take a few buttons, but it was a very challenging task to cast a device that could make 100 candles at the same time with only the smelting and casting process of the Wei Kingdom.

Because if you want to use the new candle manufacturing process pioneered by the craftsman Ding Jun, you need to use iron to model, otherwise, it is easy to meet the requirements.

But fortunately, the craftsmen of the Smelting Bureau have long had experience in iron modeling, and in fact, the mold they helped to build for minting coins is an iron mold, which is why Wang Fu, the director of the Smelting Bureau, patted his chest and promised that he would never mess up.

I have to say that Zhao Hongrun is very curious about this, and he wants to know what kind of way the craftsmen of the Smelting Bureau plan to cast those ten candle-making instruments.

Therefore, he wanted to see the whole process of making this instrument by the craftsmen of the Metallurgical Bureau.

Now that Zhao Hongrun is the direct person in charge of the Smelting Bureau, Wang Fu naturally will not refuse the request of His Royal Highness King Su, he just reminded Zhao Hongrun that the location of the casting equipment will be very hot, quite hot.

In this regard, Zhao Hongrun didn't care, thinking to himself, where is the heat energy hot?

It wasn't until Wang Fu took him to a hearth outside the city that Zhao Hongrun realized that he was wrong.

The so-called hearth, in fact, is very similar to the blast furnace that Zhao Hongrun intends to build, and it is also a smelting place covered with a lot of thick earth, which looks like a small dirt slope from the outside, and its appearance is not good, except for a high chimney towering out of the surface.

But in fact, there is a lot of things inside.

For example, under this small soil slope, about six or seven zhang high underground, the Wei people dug out a space that was half of Suwang's mansion and hollowed out the soil inside. The whole room is covered with green bricks, and many wooden pillars support the whole room, like an underground palace.

Obviously, the Wei people have long considered the issue of thermal insulation.

In the afternoon of the next day, Zhao Hongrun and several Zongwei were under the leadership of Cheng Wangfu of the Smelting Bureau. Using the entrance on the other side of the small dirt slope, you enter the hearth through a tunnel-like passage.

Because it is deep underground, the whole room is very insulated, even if the stove in the center of the room has not been lit, the room is already very stuffy, let alone after the huge stove is lit.

"Was this what the king ordered to build?"

In the stuffy hearth, Zhao Hongrun wiped the little hot sweat from his forehead. Ask Wang Fudao.

Hearing this, Wang Fu shook his head and explained, "I borrowed it from Yu Bu." As he spoke, he pointed to the gray soil in the twenty or so baskets in the corner, and added: "This is a workshop used by Yubu to burn bricks, and occasionally some porcelain, pottery or something. ”

Zhao Hongrun nodded, looked around, and asked casually, "The furnace of our Smelting Bureau is still under construction?" ”

"Hmm!" Wang Fu nodded when he heard this: "The people from the Construction Department said. It will probably be completed by the end of this month. At this, his face showed a little joy. Licking his lips, he said, "When the time comes, our smelting bureau will have its own hearth." ”

"Huh." Zhao Hongrun smiled slightly, and then advised: "The matter of retrieving the soil in various places can be accelerated, and after the earthhearth of my smelting bureau is completed, we will first try to burn a batch of bricks with the local soil near the girder." To test the effect of fire-resistant thermal insulation, what this king wants is fire-resistant thermal insulation and crack-proof fire bricks, not ordinary burned bricks. ”

"Xia Guan understands." Wang Fu also wiped the sweat that had been stuffed out of his head.

By this time, the craftsmen of the Smelting Bureau had already lit the huge furnace in the hearth. I saw that the fire in the furnace wall was big, and suddenly, the temperature in the hearth rose rapidly, and the heat was unbearable.

At the same time, some craftsmen slowly pushed a heavy and huge clay mold into the inner wall of the stove in an iron plate.

Seeing this, Zhao Hongrun had to secretly praise the wisdom of the ancients.

You know, how to use the current technology of the Wei State to cast iron molds, even Zhao Hongrun did not know for a while, but the craftsmen of the Smelting Bureau have already thought of a good way: they use the clay of baking porcelain to make an earthen mold first, bake it into porcelain at high temperature, and then pour the molten iron melted with dozens of crucibles into the soil mold to create the required iron mold in one step, and after the molten iron cools and condenses, only the porcelain needs to be broken to obtain the formed iron mold. The follow-up work is nothing more than to trim the inner wall and make it as smooth as possible.

I have to say that this way of melting cast iron molds opened Zhao Hongrun's eyes, and he couldn't help but secretly praise in his heart: The wisdom of the ancients is unfathomable!

But then again, staring at the birth of the first candle-making iron mold, even if Zhao Hongrun was just watching from afar, his face was red from the high temperature in the house, and his skin was hot, especially a pair of eyes, because he saw the roaring stove from time to time, so that even after immediately shifting his gaze, he seemed to see everything with a little red.

After repeating this several times, Zhao Hongrun only felt a tingling pain in his eyes, and the tear glands secreted tears uncontrollably.

may have noticed Zhao Hongrun's behavior of rubbing his eyes with his hands from time to time, Jucheng Wang Fu was shocked, and hurriedly persuaded: "His Royal Highness King Su, it's very hot here, you better go outside and wait for news." ”

Zhao Hongrun shook his head, and looked intently at the craftsmen who were busy back and forth shirtless, only to see that the craftsmen of the smelting bureau, especially closer to the stove, were roasted and sweated like pulp, as if they had just been fished out of the water.

Compared with these craftsmen on the front line, people like Zhao Hongrun are just watching from afar, what is it?

It is undeniable that the closer you are to the furnace, the higher the temperature, and within three feet of the furnace, it is not a place for people to stay, but the craftsmen do not care about the heat, and they have to pull out the mold of the clay baked in the furnace.

I have to say that when the iron-cast furnace door opened, even Zhao Hongrun, who was standing in the distance, felt a scorching heat wave rushing towards him, not to mention those craftsmen, Zhao Hongrun could even hear the faint sound of the body hair of the craftsmen being roasted into ashes.

"Off...... Close the door! ”

After the clay mold was pulled out, one of the craftsmen screamed, and then a group of people turned off the stove in the sweltering heat. Immediately, these craftsmen in the hottest environment rushed to the side where Zhao Hongrun was, pouring buckets of cold water on their bodies.

Although Zhao Hongrun wanted to tell them that pouring cold water on the body when it was roasted hot would be very harmful to the body. But after thinking about it, the cold water had already been roasted into warm water, and he shut up in amusement.

"Rejoice! Joyfully! ”

"Hahaha!"

The craftsmen were amusing each other, and one of the craftsmen noticed Zhao Hongrun, who was watching them, and hurriedly walked over and reported: "Your Highness, the clay mold has been baked and formed, and the rest is just to pour the smelted molten iron into it." You can get the iron mold. ”

Zhao Hongrun nodded and asked, "Will it crack, this king is referring to the clay mold." ”

The craftsman grinned and said, "Your Highness, rest assured, since that accident, the people of my Smelting Bureau have been much more cautious. What's more, this clay mold has at least one palm...... No, at least one foot thick is too thick to crack easily. ”

He was slightly embarrassed. Because in his words, he revealed the truth that he had not yet adapted to the ruler system.

However, Zhao Hongrun doesn't feel anything about this, after all, everything has a process of adaptation. It is not surprising that a group of craftsmen who used to measure length with their own body anatomies suddenly switch to rulers.

In contrast, Zhao Hongrun was more curious about what the other party said about "that accident".

Probably noticing the confusion on Zhao Hongrun's face, Jucheng Wang Fu sighed and explained in a low voice: "In the early years, when I made the iron mold for coinage for the household department of the Smelting Bureau. Due to lack of experience, the clay mold made is not thick enough, so that it ...... The clay mold cracked, and the molten iron flowed everywhere. …… A craftsman couldn't dodge it, and was swallowed up by the gushing molten iron. Ordinary body, it can really be said that there are no bones......"

Zhao Hongrun gasped in surprise when he heard this.

Of course, he knows the temperature of molten iron, with human flesh and blood, being poured with molten iron, there is no reason to be spared, not to mention that flesh and blood do not exist, I am afraid that even bones will not be left, and there are no bones worthy of the name.

Zhao Hongrun silently looked at the craftsmen who were smiling because of the molding of the clay mold not far away, and couldn't help but feel a little sad in his heart.

It is said that the soldier is the most dangerous profession in the world, but how many people know that there are many positions that are more high-risk than the soldier? For example, the craftsmen in front of them who are in danger of their lives at any time.

"Do a good job, this king is worthy of treating you badly." Zhao Hongrun sincerely and sincerely assured the craftsman in front of him.

Maybe the craftsman didn't hear the weight of Zhao Hongrun's words, but only took it as encouragement, smiled "eh", and continued to be busy.

This made Zhao Hongrun feel even more worried.

They carefully inspected the clay mold, filled the cracked parts with clay, and then pushed it into the furnace to bake, and when there was no cracking in the inside of the mold, they carefully polished it with a file, striving for perfection, so as to polish the inside of the mold smoothly and flatly.

After all, whether the inner wall of the soil mold is flat means whether the final formed iron mold is smooth and flat.

As for the final process of pouring molten iron, it seems to be untechnical, after all, the real complexity is how to bake the previous clay mold.

It was busy until around the end of the day, when the furnace had long been extinguished, and the molten iron poured into the clay mold had gradually cooled down naturally.

In order to cool down quickly, the craftsmen of the smelting bureau from time to time wet the outer wall of the clay mold with water, and in this way to determine whether the molten iron inside has cooled down, after all, if it is not cooled, the water will be poured on the outer wall of the clay mold, and there will be a sound of squeezing.

And when the molten iron has completely cooled and solidified into an iron mold, at this time, Jucheng Wang Fu handed a wooden hammer to Zhao Hongrun.

Zhao Hongrun knew what Wang Fu meant, and the other party wanted him to smash the outer layer of the clay mold, which was the same as harvesting the spoils after winning the battle.

However, Zhao Hongrun handed the hammer to Ding Jun, a craftsman who was shirtless and his skin was still red: he didn't think that he was qualified to pick up the hammer just by watching from a distance.

"Ding Jun, you and all the craftsmen present will work together to break the clay mold." Zhao Hongrun commanded.

The craftsmen, you look at me, I look at you, they are all a little surprised, they saw respect in Zhao Hongrun's gaze when he looked at them, which made them really a little flattered.

"Your Highness......" Bureau Cheng Wang Fu also looked at Zhao Hongrun in surprise.

But after seeing Zhao Hongrun hand the hammer to Ding Jun, who was also surprised, he took three steps back, shook his head and said with emotion: "This king is just watching from the sidelines, and he didn't help from beginning to end, this hammer, this king is not qualified." ”

"His Royal Highness King Su ......"

Wang Fu was moved by the words, and after taking a deep breath, he looked back at the craftsmen who were a little dazed, and shouted loudly: "Your Highness said, the credit for this time is to all the craftsmen of my smelting bureau!" …… Ladies and gentlemen, smash the clay mold and let His Royal Highness King Su witness the success of our smelting bureau! ”

"Yes!"

The craftsmen picked up the wooden hammers one after another and surrounded the tall and thick clay mold.

"One!"

"Two!"

"Three!"

"Smash!"

"Bang bang bang!"

Dozens of wooden hammers were smashed for a while, and then the thick and full foot of the clay mold was smashed, only to see the porcelain pieces shattered, and finally the iron mold hidden deep in it was revealed.

Craftsmen, look at me, I look at you, and suddenly a cheer erupted.

"Whoa, whoa!" (To be continued.) )