Waiting for the arrival of chromite ore (to make refractory bricks), laying the furnace liner, and the most critical baking and hardening furnace, things that should have been completed in July were postponed to August.
After a long period of time, Klavasen found time to complete the second wooden centrifugal blower, and his main task of making clay molds for casting was successfully completed.
It was a mold composed of two molds. It was fired from fine clay and mixed with lime and zircon powder. It was smoldering in the fire for two days and finally became a very hard texture. Pottery mold.
It can be said that in order to meet the needs of Clavarson, the potters of the Ross tribe finally had the intention to make more advanced pottery.
For ordinary daily use of pottery, clay is simply burned. The black pottery and brown pottery produced are suitable for daily use.
Potters have long known that adding some mineral powder to clay can greatly improve the performance of pottery. However, the result of this is that the cost has soared, and its selling price will naturally increase. For a long time, there has been a lack of consumers for higher pottery prices. Now that Klavasen has paid for it out of his own pocket, the skills everyone has hidden in their hearts have finally been put to use.
It wasn't just the hard clay mold that was needed to cast the hemispherical cauldron that was fired.
Also smoldering in the charcoal fire were as many as four sets of molds for casting ax heads.
Potters will join forces with blacksmiths. They will first cast the incredible pig iron as if it were cast bronze. The only thing to note is that the temperature of the molten iron is higher.
So, apart from the slight difference in temperature, are the processes between the two very different?
Even Klavasen has never done pig iron casting, and his knowledge is all guesswork.
Let's just follow the pattern of casting bronze. Maybe as long as the mold is made stronger, everything will be fine.
They made molds according to the pattern of casting bronze axes, and one mold could cast four ax blades.
Times have changed. In today's era, no one pursues a bronze ax anymore. The reason why the Russians no longer pursue it is that the cost of materials is really high, and secondly, iron axes made from ordinary iron blocks, The performance is comparable to that of the bronze ax.
Especially in the current era of technological innovation, carbon steel axes with quenching and carburizing processes are already available, which makes the previous tools seem to be too poor.
After all, the purpose of pouring molten iron is to obtain iron tools more efficiently.
But from the beginning, Klavasen ignored Rurik’s teachings on carbon proportions.
He felt that there was not much difference in essence between cast iron and forged iron. He thought that if he worked hard to produce axes and swords, it would be faster than casting them directly. Perhaps only after experiencing a real failure could he realize that pig iron, wrought iron and steel are essentially similar but also fundamentally different.
But it's just an ax blade that can be tied to a wooden stick. It's okay to use such an ax as a daily tool or a weapon in battle. At least it's enough for enemies wearing only animal skins.
A total of five sets of molds were fired and finally turned into a solid object.
They are indeed hard, and their resistance to the erosion of molten pig iron is still a bit worrying. The only good thing is that no one thinks that these molds can be used a second time.
In the minds of potters and blacksmiths, the mold that can be used many times is probably the iron mold. It is an expensive treasure and its use is limited to the casting of bronze utensils.
To make larger bronze castings, the Russians have always used disposable molds, and the castings are naturally cooled. The way to take out the castings is to smash the molds with a sledgehammer.
The pig iron casting planned now, no matter how painstakingly crafted the mold is, it cannot avoid the fate of being smashed into pieces.
Fortunately, the broken bits are mixed with new clay and can be reshaped into new molds in the fire.
No one could see its future clearly before the casting took place.
Even Rurik, when all these molds were moved to the stove and moved to the exit of the hardened pottery tap trough, when he saw these well-made molds, he first praised them, and after asking about the materials used, he also A little worried.
Rurik's biggest worry was that the hot molten iron would melt through the mold.
He grabbed his hair and asked Klavason: "Maybe you should add some chrome ore powder to the mold to make it more resistant to high temperatures."
"Oh, my lord, this is the best mold the brothers can make. When the new mold is made, I will try it according to your plan."
After saying that, the potters behind Klavasen all laughed.
Rurik looked at them and nodded with satisfaction: "I thought that you, Klavassen, could complete the casting. Now it seems that I must unite all the potters."
Clavarson, who smelled something different, said hurriedly: "Sir, if you want to cast on a large scale, you must rely on their power. And I, I am weak."
"That's true."
For a long time, Rurik's main focus was on blacksmiths, shipbuilders and carpenters. It seems that the potter's work was limited to making cooking utensils and other cheap containers, and he was ignored by himself.
Rurik hurriedly asked the names of all six potters, confirmed their family addresses in the tribe, and nodded silently to remember them in his heart.
He composed himself: "It seems that the future work will really require the cooperation of the blacksmith and the potter."
"Indeed. They make the best clay molds, and my family handles the smelting."
Klavason said a lot of nonsense, but in fact he just hoped that he would not take on other jobs too much, because there are specialties in the art industry.
"It seems that I have given you a lot of work." Rurik put his hands on his waist and called the potter to his side, "Let's do it. From now on, pottery making and iron smelting will be combined, and you people will specialize in making the pottery I need. Mold. As for the price, I will pay according to the usual rules." Rurik also added that he would not default on wages.
Usually Ross tribe potters sell their products, most of the time pricing them by weight. In order to sell for more money, of course they can make the pottery small and heavy. Even if they do this, the buyer will realize that they are being deceived.
Both buyers and sellers are smart people, so the model of exchanging the weight of the pottery for silver and copper coins in equal proportions within the tribe has remained relatively stable.
A huge, blackened furnace gives a sense of oppression to all who approach it.
Rurik often paid attention to the occasional twitching eyes of the potters, who were looking at the blast furnace!
"Oh, it looks like the opportunity is ripe. Klavasen, you come with the mold and we can finally start working."
"Of course. There is also a second blower, which has not been moved out yet." Klavasen added enthusiastically.
This old guy has always been particularly interested in the smelting process, and he is obviously eager to become a witness to the miracle immediately.
"Then let's get started!"
Rurik announced a great start. He clapped his hands vigorously and shouted slogans.
The first to take action were children like Kamne. After a while, Kawei, who was holding the blower together with the mercenary captain Yevro, finally walked out of the house.
At the same time, a group of mercenaries became the cheapest labor force. They wore simple and compact linen shirts, ignoring the blue-grey clothes stained by toner. They didn't mind getting dirty, as the clothes quickly became soaked with sweat and everyone was almost guaranteed to end up shirtless.
There are mercenaries on the steps next to the blast furnace, taking the bundled charcoal blocks handed by their companions one after another, or simply throwing a bundle of firewood into the furnace.
There are also mercenaries who are checking whether the clay that seals the slag outlet and the taphole is properly filled.
The slag outlet is designed at a higher position, and the diversion trough is also located at a higher position.
There is only the taphole, which is at the bottom of the furnace. It is an inclined hole leading from the bottom of the furnace for the flow of pig iron. The molten iron will flow into a clay-fired diversion trough, and finally a clay crucible will receive it, or it may be directly diverted into a mold for casting.
It took them nearly half a day to stuff a large amount of firewood and charcoal into the stove.
It was almost evening again, and Kawei handed a fire to Rurik who was standing on the top step.
"Honey, throw it in and light the stove."
"Okay! Let's put the ore in when the furnace is hot." After saying that, Rurik glanced at the ordinary hematite and magnetite piled on the ground like a hill.
At the same time, hundreds of people gathered around the huge stove, including Rurik's mother and his future wives and concubines.
Seeing that his friend was a little hesitant, Kawei shouted one last time: "Rurik, throw it away!"
There is nothing to hesitate about anymore.
Rurik's little hand loosened and the torch disappeared into the stove.
At this moment, two centrifugal blowers that had been on standby, controlled by strong mercenaries, began to spray strong airflow into the furnace.
In the dark furnace, a solitary fire took some time to ignite the charcoal firewood. However, the influx of fresh air was too strong, and the carbon firewood was igniting quickly.
At first it was just some green smoke, but the smoke became thicker and thicker. The strong smell of burning wood forced Rurik to cover his mouth and nose and retreat from the steps.
Not long after he came down, he suddenly turned around amid everyone's cheers and saw the red flames, just like the magnificent tail flames of a jet fighter, gushing out powerfully. Perhaps the only thing that made him unhappy was that the flame was red.
"That's great. Did we succeed?" Klavasen's impatient look left Rurik speechless.
“Where did we succeed?”
"Look! The stove, it's burning."
"No!" Rurik shook his head vigorously, "What does this mean? It's just the beginning."
Klavathon and his allies beamed with enthusiasm. "Well, my friend. When do we put in the ore?"
"When?" Rurik held his chin and thought for a moment, then said suddenly: "We can't expect to put fresh fish on the fire and grill it for a blink of an eye, and expect the fish to be grilled with fragrance and oil. You know I mean, right? That's the flame! When it turns yellow fire, put in the ore."
"Well done! Hopefully I'll be able to see molten iron soon."
"Forget it, we have to smelt a lot of ore this time, and a lot of molten iron will flow out in the end! The casting mold you can provide is not enough."
"Ah?!" Clavarson was shocked, "This... maybe we should put less ore in it for safety reasons. I'm afraid it will collapse again."
"No. Don't worry about it collapsing. It's me! I'm the one who guided you to make the new stove. It won't collapse on the first use." Rurik's attitude became very determined. He pointed at the pile that was close to his own. The tall pile of ore, "Now that we have brought them here, let's smelt them with all our strength!"
"But there is too much molten iron, and you just let it flow and condense on the ground? We don't have enough molds."
"It doesn't matter."
Rurik not only said it with his words, but his attitude and actions showed his attitude.
"Ah. If we do this, wouldn't it be a serious waste? Hell, if it doesn't work, let's make a simple mold now. Even if the quality is not good, at least the shape of the tool after casting can be guaranteed."
"Oh?" Rurik was a little surprised. He thought for a while, if Klavason and the potters took advantage of the fact that the molten iron has not yet been smelted and spent two or three days firing a batch of clay molds, even of poor quality, of course, The erosion effect of molten iron is serious, but the shape of the casting can still be guaranteed to a great extent.
After all, this era does not have too many technical requirements for castings. They are just used as production tools, such as commonly used drafts, axes, or shovels. People do not require them to be exquisitely made, but only seek practicality and cost-effectiveness.
In fact, the problem that Rurik thought of was not at all about how to ensure the one-stop work from opening the taphole to completing the casting as soon as possible.
Pig iron is pig iron, even if it solidifies on the ground, it is still pig iron. Even if there are some small sand and stones attached, a few pollutants will eventually turn into gas or flowing slag after secondary processing.
Rurik knew that the purpose of the Klavasen family and other blacksmith families hoarding sponge iron was to have enough primary materials for subsequent blacksmithing.
There were only five Ross blacksmith families, and they still had the habit of signing treaties with each other, becoming a rudimentary and primitive blacksmith guild. Their processes have long been upgraded to the point where they can process mild steel.
As long as conditions permit, they will not hesitate to process the iron on hand into low carbon steel, so that the southern merchants who come to Roseburg like migratory birds every year can buy the steel tools and weapons on hand at high prices.
To process iron into steel, you need to use some processes to control the internal carbon ratio to an appropriate level.
Smelting a large amount of molten pig iron to condense it into iron ingots of white iron, which is used as an alternative to stockpile.
As long as the tribesmen are not picky, the cast white iron can be used as agricultural tools.
But here in Rurik, he just wanted to smash these iron ingots into finger-sized pieces and put them in a traditional stove to undergo long-term baking at about 900°C. A large number of small iron ingots were constantly turned by the tongs, and their The carbon content decreases rapidly, and finally merges with each other, and is fished out like a huge hot iron weight for forging.
This is the method of frying steel, and it is also the method that Rurik thinks can be realized in the Rus tribe, and is the fastest and most cost-effective way to produce low-carbon steel.
For the time being, Rurik had no intention of informing Klavason of his plan to make low-carbon steel using the steel-frying method, and he couldn't force the old guy and other blacksmiths to realize it instantly.
Once the furnace is lit, it would be a bit of a fantasy to expect that it would take half a day to burn enough to melt pig iron.
