Release that Witch Chapter 69: Cannon making

Four days later, Northern Slope Mine firing room backyard.

Two deep holes have been dug on the ground in the yard. Each hole is round, narrow up and wide. The inner diameter of front segment is about 20 cm, and the inner diameter of the rear end is expanded to 26 cm. These holes are the molds that Roland intends to use to cast the blank. The inner wall of the hole has been baked by Anna, and the surface soil is sintered into a whole, as if a shell is attached. The downward direction of the medicine chamber is to obtain better tube wall quality during casting, and the more scum and air bubbles are contained in the upward direction. The size of all the caves was calculated from the shells. He roughly remembered that the so-called six-pound and eight-pound cannons were named after the weight of the shells, so a few twelve-pound iron **** were poured first, and then according to the iron The diameter of the ball plus the wall thickness of the gun is used to calculate the inner diameter of the mold.

Under situation, which lacks a measuring tool, Roland simply customized the standard. He intercepted a piece of iron bar about as wide as his ring finger nails to set it as the basic unit. One centimeter, and then made other sizes of iron bars, and Engraved with segmented lines.

The diameter of a twelve-pound iron ball is about twelve centimeters measured by a rough iron ruler. He set the thinnest part of the tube wall to four centimeters. To seven centimeters, the inner diameter of the mold was obtained. As for the length, although he knows that the cannon has a double diameter, but the impression only has the double gun diameter of the battleship and the main station tank. As for the antique front loading gun, he really doesn't know.

Considering that the shorter the body tube, the lighter the weight, and the more material saving, Roland waved his hand and took the value of 1.5 meters. If the test results are not satisfactory, adjust the then it will be alright later.

cannon was originally invented by ringing iron bars on the wooden core material and adding iron powder, then strengthening with iron hoop, and finally burning out the core material in the barrel, just like the storage wooden barrel. Roland of course knows that this type of cannon has the risk of leaking and blasting easily, so it directly adopts the process of integral casting and boring machine drilling. For a steam boring machine, drilling a six-pound cannon or a twelve-pound cannon does not differ in difficulty.

In the concept of caliber being justice, he naturally chose a twelve-pound gun with a larger muzzle and a thicker barrel. Further up, it is not easy to use as a field gun. As for the weight of the projectile, whether it is calculated by shot or iron, it is not important. It can hit then it will be alright. After all, he was learning from history, not playing with replica models.

"Get started," Roland took a deep breath, said to Anna. The latter nodded, grabbed a steel ingot, and hung over the opening. The green flames ignited, the steel ingots quickly turned red, and then melted, forming a small waterfall of molten steel, flowing into the cave. The surface of the molten steel is red-orange, and the inner core turns incandescent, and its brightness is hard to see directly. In order to protect the eyesight of witch, Roland also purposely set up a support near the opening of the hole. She only needs to determine the position in advance and lean her arm on the support pad, so that she can watch the molten steel without looking into the hole.

These steel ingots are slowly accumulated normally. The strength of Anna alone cannot open the era of large steelmaking, but small batch production is important to her. After the temperature level of --, the most difficult to achieve, is solved, You can get better qualitative steel by frying the steel.

This is why Roland dares to customize the barrel size. Compared to the pig iron barrel and bronze barrel, the steel cast barrel obviously has higher strength. Even if the size is not right, cannon will not easily explode.

The molten steel is gradually rising, and the remaining steel ingots are also rapidly decreasing. You can see that Roland can't help but feel some heartache. When will he wait until he can build a pile of chimneys and blast furnaces on the territory to make endless steel? For a long time, steel output was one of the standards for measuring the strength of the great powers, and he felt it now.

Filling the two molds, Anna's cheeks turn red. Roland drew takes action silk and gently wiped the sweat on the tip of her nose. At first, the Anna will show a little resistance, and now it has been obedient and closed its eyes to let Roland do it.

The falling bangs is stained with a red edge under the reflection of molten steel. The soft neck makes people want to bite. When he stands high, the slender collarbone exposed by the other person through the collar will enter his vision. It was close enough to smell the fragrant fragrance from her.

"cough cough, all right ..." Roland put away the handkerchief, and at the same time pulled back the restless emotions, "Get here today. Good job, I will order the kitchen to reward you with a black pepper steak.

Not yet, he thought, it would inevitably be suspected of doing so. Wait, wait until she is truly free ...

Anna opened his eyes. Although sweat was wiped away, his face seemed redder than before. She nodded to Roland and gently answered Yeah.

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In the next few days, Roland will travel between the castle and Northern Slope Mining area.

In addition to the barrel, he also needs to make a sufficient number of boring tools.

The manufacturing method of this tool for drilling is similar to that of the gun barrel. Its diameter is exactly the same as the shell. After it is taken out of the mold, it is heated again by Anna and processed by a hammer. It is very different from the ordinary spiral knife in shape, at first glance it looks like a blunt iron rod. The only difference is that there is a gap in the top of the head for discharging the metal fragments. The last step is quenching to increase the hardness of the boring tool.

Unlike the high-precision drills of modern boring machines, Roland only needs an iron rod that can punch holes. Considering the high wear rate, he and Anna made five simple boring tools in one week. Before that, the steam boring machine had fully verified its ability. The output of -- pig iron barrels increased rapidly from two per month to ten per day.

When everything is ready, the blanks are planed out of the pit by the miners, the surface scum is cleared, and then the horse carriage is transported to the smithy.

These two shells have almost consumed the steel accumulated by Roland, and it is no exaggeration to say that they are priceless. During the transport, the prince ordered Carter and two Knights to take charge of the whole process of guarding, which made Chief Knight feel a little bit extra. Who would come to steal something so deadly?

The blacksmith leveled and polished the appearance of the cannon according to the prince's request. After being polished by whetstone, they were then sent to the castle backyard non-stop. At this time, the two round solid steel bars were dark gray in appearance, exuding a heavy metallic luster.

Roland can't wait to put on a boring tool, and fix the blank in place with Carter so that the top of the cutter head just hits the center of the steel rod.

Facing this historic moment, Roland pulled down the valve of steam engine. The boring tool started to run slowly, and soon it rose to a stable speed.

"Go ahead!" the prince shouted.

Chief Knight pushes the sliding base to control the depth of contact between the blank and the boring knife. When the blade touches the gun barrel, the harsh noise made by the steam engine suddenly covers the roar. The lard, which acts as a lubricant, was squeezed into the borehole, and the black foam and curly wires emerged. The onlookers of witches have withdrawn from the wooden shed, and only Lightning still insists on staying in place. It seemed to her that these dark machines were more beautiful than any scenery.