Chapter 298: Solving the technical problems of building large ships

After becoming the second navigator under Her Majesty, Amerigo began preparations for selecting crew members. At the same time, he requested that large ships of 200 tons or more must be used to ensure navigation safety. After all, a boat that is too small is not very resistant to storms.
Crossing the Atlantic Ocean is not the same as going to India. The route to India is basically along the coast of Africa. The only sea that crosses is the relatively calm Arabian Sea. But crossing the Atlantic is different. Although Amerigo has not been to the Americas, it has also been heard that the depths of the Atlantic Ocean are still very strong.
Marin naturally agrees with this. It is estimated that Columbus would return for at least a year and a half, but it would not take much time to go to Grenada. Columbus's fleet crossed the Atlantic from the Canary Islands, but it took 70 days. From Emden to the Canary Islands, it took just over a month. Therefore, from Emden to the Windward Islands, in fact, as long as more than three months, more than half a year can run a round trip. So Marin had enough time to prepare.
For safety, Marin decided to wait for the completion of the two "250" class armed merchant ships of the Tholencher shipyard and hand them over to Amerigo. Class 250 merchant ships are now mature in construction technology and can be completed in a few months. During these months, I just brought Amerigo to the sea with a group of new sailors.
Although Marin has a group of old sailors who have been rotated from the Columbus fleet, Marin does not intend to use them all. Because he needs to train more sailors. Therefore, Marin only picked up a part of the old sailors to follow the ship, and first used those more than 100-ton boats to practice big voyages in the North Sea. Most of the sailors on board were selected from fishermen's families and some young sailors trained by sailors. In this way, they can be carried by the old sailors, and they can become old sailors as soon as they sail down.
表示 In order to show the importance to navigation, Marin also accompanied Amerigo personally to inspect the two shipyards of Tholencher and Emden. But the result of the inspection made Marin frown ...
The Huentholencher shipyard is nothing, just step by step. But at the Emden shipyard, they encountered technical difficulties ...
It turned out that Marin asked Emden Shipyard to try to build a 500-ton ship, and the difficulty was definitely greatly increased. Elsewhere, the ribs in the keel of the shipbuilding became a big problem ...
Generally speaking, European-style sail wooden boats are laid with keels and then covered with wooden boards. The keel is somewhat like a fish bone, with a main main keel, plus many curved "ribs".
The main keel is still very easy to find. Its only requirement is long enough. For example, Da Gama explores India's flagship "San Gabriel", which is 25.7 meters in length. Of course, this is the length of the upper deck. The main keel at the bottom of the ship, about 20 meters long is enough. The 20-meter-long oak is difficult to find, but it can still be bought as long as the price is high.
Alas, it would be difficult to get a longer keel. For example, the Swedish "Gothenburg", Marin had read their retro shipbuilding articles, and knew that the oak tree they used to make the keel must be a "great" oak tree with a tree age of 300 years and a diameter of 5 meters. This kind of oak tree is very rare in Europe. After all, Europeans have been cutting and using oak trees for thousands of years. Of course, the keel of the Gothenburg was also very long, reaching 40.9 meters.
超 Such a long wood is very precious in Europe right now. Because 300-year-old trees are rare in Europe. However, Marin knew that in this America, trees were rarely cut down because there was no developed civilization. Therefore, in North America, there are many super old oak trees that have grown for hundreds of years and are forty to fifty meters long. Because, for thousands of years, no one has logged on a large scale in North American forests. As a result, Marin had plans for logging and shipbuilding in North America. In North American forests, extra long keel oaks like the Gothenburg keel are not expensive at all, everywhere ...
The Spaniards, in order to build the Spanish galleon, later moved the base of the large ship to the Americas. Marin remembered reading in an article that after about 1610, Spain moved its shipbuilding base to Havana, Cuba, in order to directly use the local abundant timber resources.
Of course, Marin is now building a 500-ton ship, not a 1150-ton ship like the Gothenburg. Therefore, Marin does not need the wood of a 300-year-old tree that is 40 meters long, only a keel that is 30 meters long is sufficient. Although the price will be more expensive, it is not found.
However, the ribs used for large ships are very troublesome. You know, the big voyage is just now, and the shipbuilding technology is still underdeveloped.
After understanding the situation, Ma Marin was surprised to find that the ribs of this era turned out to be the shape sawn from a whole piece of wood ...
You know, the ribs are not the same as the main keel. The main keel is straight, but the rib is curved. The ribs are nailed to the main keel. Generally speaking, the ribs installed on the bow of the ship are a pair of "V" ribs, while the ribs in the middle of the ship are "U" shaped. The "V" rib is simple, and two straight long boards can be nailed to the keel. However, the "U" -shaped ribs are more troublesome, but the most commonly used ribs of a ship are "U" -shaped. Moreover, in this era, the "U" ribs used by people are mostly curved ribs sawn from relatively thick logs, which is a waste of wood.
It is better to make the barge smaller. If you build a large ship, it will take hundreds of years of oak wood to process the ribs, which is very wasteful ...
Marin was a bit surprised. In his memory, when the antique ship "Gothenburg" used retro technology to build the ship, it was obviously made by steam softening straight wooden boards ...
Alas, Marin didn't think about it, even the original Gothenburg was an 18th century ship. Shipbuilding technology at that time was definitely much stronger than at the end of the 15th century. It can even be said that it is because of the great navigation that has promoted the advancement of European shipbuilding technology. After all, "need is the mother of invention."
He doesn't know when the technology of softening and changing the shape of the ribs with steam came out, but at least he knows that his technology is not available in his shipyard right now. Even some Portuguese shipbuilders have not heard of this technology.
Therefore, Marin determined that this is still a technology that has not yet appeared ...
Seeing that Emden Shipyard was worried because he could not find enough rough oak to process the curved ribs, Marin directly described the technology he had seen using steam to soften and change the shape of the ribs.
The old shipbuilders are doubtful about this. However, the facts speak louder than words. Marin immediately sent someone to make a long box to put the wood to be softened. Then I asked the blacksmith to make a large iron pot with a fixed lid, and a pipe to guide the water vapor ...
After the stuff was ready, under Marin's command, the craftsmen put the softened wood into a long box and sealed it half. Then, the big wok started to boil water, and the pipe passed water vapor into a semi-sealed long box ...
In this way, after steaming the buns for 5 or 6 hours, the board finally softened. But Marin knew from previous articles about the construction of the Gothenburg that this softening lasted only 20 minutes. So he quickly ordered the artisans to bend and deform the wood within 20 minutes ...
Sure enough, after 20 minutes, the wood began to harden, but before it was bent and deformed, it did deform. However, there are signs of a rebound.
As a result, the craftsmen simply made a groove, which was used to clamp the wood that needed to be bent in order to get the board to the shape required for shipbuilding. Wait for the wood to air dry, which is exactly the shape that shipbuilders need.
几天 After a few days of experimentation, the craftsmen finally became familiar with the process. In this way, the cost of manufacturing a few meters of curved boat ribs is greatly reduced.
Before, they saw off curved ribs from thick logs, which was a waste of wood. Because the rough logs of sawn ribs are mostly wasted.
After using the steam softening technology provided by Marin, they can directly process ordinary soft wooden boards of several meters long into steamed boat ribs. In this way, a lot of cost can be saved. Because a few meters of straight wooden steps are easy to find and cheap. Unlike the previous need to find very thick logs, the price is more expensive, and wood is wasted.
In this way, Marin easily solved a technical difficulty in building a large ship by using the processing method of the Swedish "Gothenburg" antique ship that he had seen in previous lives. The 500-ton warship required by Marin also continued to manufacture smoothly.
As for the issue of technical secrecy, Marin need not worry, because the craftsmen of Emden Shipyard are mostly Marin serfs. Other artisans who are not serfs have signed life-long contracts, and their families are here, but there is no need to worry about them running with technology.
At the beginning, when separating the Tholencher shipyard ~ EbookFREE.me ~ Marin considered the issue of confidentiality. Therefore, he left the Portuguese artisans without a life-long contract at the Tholencher shipyard, and Portuguese old man Vallado led the construction of "250" class merchant ships. In the future, serf artisans who want to make warships, and those Venetian artisans and a small number of Portuguese artisans who have signed lifetime contracts, have entered the Emden shipyard to make warships. In the future, the Tholentcher shipyard will specialize in manufacturing merchant ships, and the Emden shipyard will be responsible for manufacturing warships with a clear division of labor ...
Merchant ships and warships are different. For example, on a keel with a length of 24 meters, a merchant ship generally only needs 33 pairs of ribs. There are a lot of gaps between the ribs of the boat, covered directly with wooden boards.
However, in this case, because of the existence of these gaps, if the enemy's iron ball shells hit the gap during naval battle, it would be easy to break the outer wooden board and cause a "piercing" effect. In that case, water will enter the side of the ship, which may even cause a shipwreck ...
Therefore, when manufacturing warships, they often use more ribs, which are arranged tightly and tightly, without gaps, and the wooden boards are thicker outside.
This time, when the 500-ton class warship was built, the craftsmen followed Marin's requirements, leaving no gaps between the ribs. To this end, more than sixty pairs of ribs need to be nailed to the 30-meter keel, which is very compact, but it is also time-consuming and labor-intensive.
Fortunately, Marin provided the technology of steam softening and processing ribs in a timely manner, which greatly reduced the cost of rib processing. Otherwise, the cost would be sky-high ...
Marin left Emden shipyard with satisfaction, thinking proudly as he walked:
"Sure enough, the traverser is the best, the tricky technical problems that are difficult for artisans to solve, and the traverser solved it with a simple memory ..."