Super Chief

Shixiong’s "carefully reformed" smelting process really played a huge role, because after this furnace of molten iron was fully oxidized and decarburized, the steel that came out of it was pure steel, and according to Shixiong’s general judgment , This batch of steel should belong to the scope of low-carbon steel.

　　 Although low- and medium-carbon steel is not as hard as high-carbon steel, it has better toughness. In daily life and military applications, low- and medium-carbon steel is far more versatile than high-carbon steel.

　　 And low- and medium-carbon steel can also be processed by heat treatment. The surface hardness of the processed workpiece is very high, and it can even be used as high-carbon steel.

Although Shixiong did not know the heat treatment process very well, he had heard of it in general, so he told Lieutenant Ferguson what annealing is, what is tempering, and what is quenching. After these heat treatment processes, he asked this The little brother went to the experiment by himself.

　　 Anyway, the amount of steel produced in this furnace is large enough to be enough for Lieutenant Ferguson.

　　 But Major Ferguson is obviously not thinking about the steel that has just been tempered. He is now making rifled wooden lathes with the wood family.

　　 That's right, the first meaningful thing that Lieutenant Ferguson did after coming to the High Tree Tribe was to make a wooden lathe with Mu and his family specifically for rifling the barrel of the gun.

　　 This is an extremely backward lathe in Shixiong's eyes, and the power is neither water nor steam, let alone electricity, not even the most basic animal power, but pure human power.

　　 But this is indeed a lathe, even if it is very crude, even if the power used is primitive, but this is still an out-and-out machine tool, because the use of this simple equipment can complete the work of rifling the barrel.

This lathe is very long, more than three meters long. It is actually a wooden shelf on which two very flat and straight wooden rails are laid. A wooden sliding table that can fix the hook knife is erected on the rails, and on the two rails. Between is the fixed position of the barrel.

This weird-shaped lathe is called "manual wooden broaching machine", and there are three core parts of this broaching machine, one is a hook knife specially used for rifling, and the other is a tie rod connecting the sliding table and the hook knife. The screw, the other is the most complicated linkage mechanism, which involves the core part of the barrel that rotates at a constant speed.

The 　　 hook knife is the core part specially used to pull the rifling. Said it was a knife, but Shi Xiong couldn't bear to look directly at it because of its crudeness.

　　 This kind of hook knife is actually a steel rod slightly smaller than the inner diameter of the barrel. This steel rod is also cast, and there is a groove in a specific part. This groove is used to hold the steel sheet that has become stronger after quenching. The steel sheet is made by hand, and there are one or two protruding bands with a certain angle of inclination on it.

　　Because it is made by hand and uses a quenching process, the surface hardness of the steel sheet is much higher than the hardness of the barrel. In this era when there is no high-hardness alloy steel, this method can only be used to replace high-hardness alloy steel.

　　This combination is a hook knife.

　　 Another core part of the broaching machine is the tie rod screw connecting the hook knife and the sliding platform.

The history of 　　 screws is very long, dating back to about 400 BC. However, modern screws appeared in the middle and late nineteenth century, so in this era, screws are still extremely precious and extremely difficult to build.

　　 These screws are all made by hand. When making, first forge the nail blank of the screw, and then use a hammer to knock out the nail head and round nail body on the nail blank; then, use a saw to cut a groove on the nail head, and then use a kind of "Die" screw steel plate manufacturing thread.

　　The manufacturing process of this kind of screw is complicated and expensive, so the early screws are sold individually, and ordinary people can't master the process of screw processing.

However, Ferguson happened to have mastered this technique, so under his leadership, the seven or eight blacksmiths worked hard for a whole day to create four tie rod screws more than one meter long and more than ten hook knives. The kind of hardened steel sheet.

　　 Ishikuma didn't know how to pull the rifling. He only knew that the rifling of the barrels of later generations was pulled out with special equipment. How could he have seen manual rifling equipment in the middle of the 18th century?

　　 So this time Lieutenant Ferguson let Shi Xiong open his eyes.

　　 The hook knife and tie rod screws are fixed, and then you can start rifling.

　　 Although the diameter of the steel rod on which the hook knife is installed is slightly smaller than the diameter of the barrel, if the steel plate is added, the diameter of the hook knife is slightly larger than the barrel. So pulling the hook knife is a matter of great effort. Because the hook knife is almost pulled from one end of the barrel to the other in a "hard squeeze" manner.

　　The hardness of the steel sheet is greater than the hardness of the barrel, so whenever the hook knife is pulled from one end of the barrel to the other end, the hook knife will pull a groove from the inner wall of the barrel.

　　 Of course, under the fixed barrel, there is a linkage mechanism that is “complicated” in this era, and it is also another core part of this lathe. The function of this mechanism is to adjust the barrel rotation speed according to the length of the pulling distance.

　　 Yes, although the barrel is fixed in the middle of the two rails, it just can't move back and forth, but it can be turned.

When the worker pulls the hook knife, as the wooden sliding table moves, it will drive a tough leather belt hung on the sliding table, and the leather belt passes through a wooden pulley at the other end of the broaching machine and a small wooden wheel at the bottom of the broaching machine. Connected.

　　 When the sliding table moves, pull the leather belt, and the leather belt drives the wooden wheel to rotate. And another small wooden wheel that is coaxial with the small wooden wheel will also rotate. This small wooden wheel also has a leather belt connected to another large wooden wheel. This large wooden wheel also has a coaxial small wooden wheel. The small wooden wheel will also have a belt and another A larger wooden wheel connection...

　　 This is actually a very simple three-stage belt drive reduction device. When the sliding table is pulled, the movement of the belt pulls the rotation of the three sets of coaxial wooden wheels under the broaching machine. Because of the three-stage deceleration, the largest wooden wheel turns the slowest. In addition, the coaxial wooden wheel of the last group of wooden wheels is connected to the fixed barrel, so once the sliding table is pulled, the barrel will rotate at a very slow speed at a uniform speed.

　　 In this way, as the barrel rotates at a constant speed, every time the hook knife is pulled, a tangled rifle can be pulled out. When one rifle reaches a predetermined width, change the position to pull the second rifle.

　　 This kind of manual wooden broaching machine was the most important tool for rifling often used by early American colonists. Even after the emergence of steam machinery, this kind of manual broaching machine was still used in a small area.

　　 However, although the rifled gun of this era is not as good as pulling a rifling hundreds of times in later generations, if you want to pull a qualified rifling, you must at least broach about twenty times. So, this is a very laborious job.