Late Ming sea owl

Chapter 243 Can a Cruiser be Built?

The Ship Bureau's shipyard in Keelung Port is located on the landward side, not far from the Navy Department's headquarters building.

When Lin Hai stepped onto the land, continuous drizzle began to fall from the sky. This is the bad thing about Keelung: it rains for no reason and the sky is always gloomy.

After getting off the ship, Lin Hai did not have time to rest, and immediately convened a meeting of all the craftsmen and main managers of the Ship Bureau.

As it was dark, whale oil lamps were lit in the conference room.

"Everyone, I came here this time just to ask you, does the Ship Bureau have the conditions to build cruisers now?" Lin Hai stood and looked around at everyone present, still getting straight to the point as usual.

"Boss, there are two frigates on the slipway now?" A relatively young master craftsman was the first to speak. This man was the designer of one of the frigates and had just been pulled over from the slipway.

"What you're talking about is, of course, after these two frigates are launched. Besides, if we want to build a cruiser, we have to design it first, and the wood for the keel and ribs also needs to be selected and processed. How can we get it ready so quickly?"

Pan Dajiang took over the conversation. He is now the new director of the Ship Bureau and is mainly responsible for management work.

"That's right, that's what Director Pan meant." Lin Hai nodded and said, "Everyone, tell me, can we start construction?"

Everyone looked at each other and started talking. Some patted their chests and said it was no problem, while others said something to spoil the mood. However, Director Pan remained silent, only carefully recording the opinions of each speaker and occasionally glancing at Lin Hai's expression.

"Xue Zhong, you guys can also say something." Lin Hai said to several master craftsmen who came from Tamsui. These people had communicated with him on the road, including Pan Xue Zhong.

This guy is now a master craftsman, and the youngest master craftsman in the entire Construction Company. He and Lin Hai were the ones who designed the first Sloop ship.

He just said, "General Manager, I think there will be no problem. The Ship Bureau has already built more than ten notification ships and frigates, and the workers have accumulated enough experience."

"How many ships have you built, you ignorant boy? How can a frigate and a cruiser be the same?" Another older craftsman named Song retorted. This man also came from Cavite and is now the chief designer of the Calais ship type of the Ship Bureau.

This man had a solid level of shipbuilding skills, but he was a bit conservative and had always been dissatisfied with Pan Xuezhong's unconventional style. When the Sloop was not yet built, Master Craftsman Song had publicly predicted that the boat would capsize when it was launched, but he was proven wrong.

However, the management of the Construction Department has always been more humane, and Lun No. 1 has well implemented Lin Hai's sixteen-character policy of "brave innovation, talent-based selection, straightforward speech, and technical democracy". Therefore, Song Dajiang was not punished, and there were many people like him who spoke aggressively in the various departments of the Construction Department.

"What's the difference? It's nothing more than using dense ribs to support the hull and high-strength elbows to support the deck. I can't see the difference." Pan Xuezhong was young and full of energy, and of course he didn't give in at all. "What's the difference? Let me, Old Song, say that the frigate is like you, a young boy, and the cruiser is like your father, Director Pan. Do you think they can be the same?" Master Song still recognized Director Pan. What he meant was that Pan Xuezhong was far worse than his father.

Pan Xuezhong was a little annoyed when he heard this, but his father, Director Pan, just stopped writing with his brush and smiled. At this time, Lun Diyi said, "Okay, Old Song, stop talking nonsense and just tell me your opinion."

"Okay, then I'll tell you. It's best to make a cruiser into a plywood ship, that is, a double-hulled ship. This is the first difference. Secondly, it can't be made too slender. After all, a big ship is difficult to turn around, and it's even more inconvenient to make a turn if it's too long. What's more, a cruiser is a square-rigged ship and is not as flexible as a schooner..."

What Old Song said made sense, and all the masters present nodded frequently. He continued proudly, "Also, the ship cannot be made so thin below the waterline. Pan, you just said that the hull is supported by ribs, but the bending shapes of the ribs are very different! Hot bending is the most critical and labor-intensive process. Do you dare to say that the workers in the bureau can do it well?"

The so-called hot bending refers to the use of fire to process wood to make it easy to bend. Huiyou Company now uses the sand burying method, which is to bury the wood in wet sand to absorb moisture, which can achieve the same effect. This is a technology from a hundred years ago. Lin Hai introduced it to the Ship Bureau, but Master Song still habitually calls this process hot bending.

What Master Song said was pure specious talk. It would be fine if the workers in the Ship Bureau had no experience in building Western-style sailboats, after all, Chinese sailboats rarely use rib bending technology.

This is not to say that Chinese ships do not have ribs. In fact, other ship types besides sand ships also have ribs, but they are relatively sparse. Moreover, Fuchuan and bird ships use spliced ​​ribs, and only some Guangchuan ships use rib bending technology.

But nowadays, everyone has built so many Western-style sailing ships. The only difference is the bending shape, and there is no essential difference in the craftsmanship. Why can't they be built well as he said?
"Why can't the cruise ship be built thinner?" Lin Hai interjected with interest. The Manila galleons built at the Cavite Shipyard are generally built fatter, which he personally does not like.

Seeing that Lin Hai was interested in this topic, the craftsmen started to discuss it. Some said that the cruiser could be made thinner, while others strongly opposed it. Everyone gave their reasons, and no one could convince anyone else.

In fact, this question involves one of the most critical issues in ship design - the underwater line design of the cross-section, simply put, it is a question of whether it is a U-shaped bottom or a V-shaped bottom.

The advantage of the U-shaped bottom is that the center of gravity is low and the stability is high, which makes the ship less likely to capsize. At the same time, due to the full underwater line shape, the rolling amplitude is small and the recovery is fast, which is conducive to artillery aiming, but rolling too fast in high sea conditions can easily cause seasickness.

Another advantage is the shallow draft, which not only improves seaworthiness, but also allows the height from the gun port to the waterline to be designed higher, so that the gun port can be opened when the wind and waves are stronger.

The disadvantages are also obvious. Although there was no fluid mechanics in that era, old shipbuilders and even old sailors could draw the conclusion based on experience: the fatter the underwater hull, the slower the speed and the lower the rudder efficiency. The result of low rudder efficiency is that a larger rudder is needed, which further leads to low speed. It's a vicious circle.

Moreover, the low efficiency of the U-bottom rudder is not entirely due to the slow speed, but also partly because the water cannot flow smoothly to the rudder blade. Of course, it is not only the cross-sectional line shape that affects this, but the longitudinal shape is also very important. Fast ships generally adopt a streamlined design.

In this regard, Huiyou Company's communication ships and frigates also have great advantages. After all, Lin Hai has the ship model drawings of the Baltimore clipper ship more than two hundred years later.

(End of this chapter)