Da Vinci and the craftsman team worked overtime to develop spring steel under the stimulation of Marin's reward. Especially Da Vinci, in order to get Marin's support to marry Lisa, he also worked very hard.
Finally, Leonardo Da Vinci and the craftsmen developed a spring steel with a little flaw...
The so-called shortcomings are because the 65Mn ordinary spring steel they make lacks chromium and nickel components. Although the content of these two elements needs to be very small, it still has a little impact on the quality. Moreover, other ingredients, such as manganese, silicon, copper, etc., are present.
But Da Vinci and others were very troublesome in order to control the proportion of the requirements given by Marin. Manganese is naturally the pyrolusite that Marin sent to Venice to buy, and copper is easier to handle. But silicon, da Vinci didn't quite know what silicon was. So, Marin simply asked him to add high-purity quartz sand to the steelmaking crucible. Then, he gave him the calculation formula, and told him the proportion of manganese content in pyrolusite and the proportion of silicon in quartz sand.
In this way, Da Vinci and others finally came up with slightly flawed (chromium-nickel-free) spring steel. Then, again, the trouble encountered in the quenching stage.
Craftsmen in this era are basically used to water quenching. Water quenching makes the spring steel harder, but also more brittle, which affects the elasticity of the spring.
Ultimately, Marin suggested that they quench in oil. It happened that the whaling ship killed a small whale and brought back a lot of whale oil. So Marin asked them to try quenching with whale oil. Then, spring steel tried it out.
In fact, Marin remembers that special steel quenching is a very profound knowledge in later generations. In addition to water quenching and oil quenching, various chemicals are added to the quenching liquid to enhance the performance of the steel.
But Marin obviously doesn't understand the quenching process, only knows that there are water quenching and oil quenching, and dual-medium quenching that mixes water quenching and oil quenching. But dual-medium quenching is very troublesome to study, and what he wants is not a high-end spring, so he simply uses oil quenching.
Because of the lack of chromium-nickel elements and the fact that the craftsmanship is not as good as modern, Marin estimated that this No. 65 spring steel is not as good as modern. Therefore, after winding out a very thick vehicle spring, it was found that its bearing capacity was limited.
Marin had never driven a car in his previous life, but he rode a scooter with springs and shock absorbers on the wheels. Its principle is very simple, that is, a relatively thick coil spring is covered outside a steel cylinder similar to an inflator.
When pressure is applied to the frame, the "pump handle" transfers pressure to the spring. The spring began to deform, but because the spring was restrained by this steel cylinder similar to an air cylinder, it would not deform horizontally, but only deform longitudinally.
When the spring is deformed, the pressure from the frame is fully offset, which greatly reduces the vibration of the vehicle body. Marin directed the craftsmen to manufacture four spring shock absorbers, installed them between the frame and the wheels of a four-wheeled carriage, and conducted experiments.
It turned out that the largest type of spring shock absorber they could manufacture, with four added up, could only bear a maximum weight of 1.5 tons. No matter how heavy the weight is, the spring is easily crushed. This kind of affordability is mostly used in small-displacement private cars in later generations. Larger private cars cannot be used.
But in this era, the weight of the four-wheeled carriage carriage is not very large. Generally, a closed compartment carrying two people weighs no more than 1 ton. Only those carrying several people like the British golden carriage will weigh 3 tons. Of course, that was also because the carriage was too wealthy. Not only did it have a lot of space, but it also used a lot of dense gold, causing the weight of the carriage to exceed 3 tons.
Generally, the weight of a two-seater carriage will not exceed 1.5 tons even if the carriage is covered with steel plates and the passengers are added. Therefore, Marin immediately ordered the craftsmen to build a two-seater (can also squeeze 3 people) carriage with steel plate protection and glass windows. The weight of the carriage (including 3 passengers) was controlled within 1.5 tons, and installed The spring shock absorber.
After testing, the shock absorption performance of the new carriage is very good (compared with the carriage without shock absorbers), and the ride is extremely comfortable. Fitted with the ball bearings that were invented earlier, the new wagon is downright comfortable.
So Marin invited Angela, mother-in-law and Felice to ride. The three women were extremely surprised after riding in this carriage with good shock absorption performance.
Then, Angela rekindled her enthusiasm for traveling around in a horse-drawn carriage. You know, every time I rode in a carriage without shock absorbers, I bumped people badly. With the shock absorbers these days, the wagon doesn't have to be too comfortable.
The ancients talked about the pommel horse fatigue, but modern people are actually not able to deeply understand it. Because, modern vehicles all have shock absorbers. Modern people take a long-distance bus, and many people actually fall asleep comfortably along the way.
But try switching to an ancient carriage? That's called a bump. Maybe you just fell asleep, and there was a sudden "bang" violent bump, which woke you up all of a sudden, and made you extremely uncomfortable.
Moreover, there were no smooth cement roads or asphalt roads in ancient times, and most of the roads were rough. Without a shock absorber, it can vomit out a person's overnight meal.
Therefore, in ancient times, every time a horse-drawn carriage traveled far away, it was a very painful thing, especially for people with weak constitutions. Even a young man like Marin is not used to riding in a carriage. Every time he travels far, Marin rides a horse. Although riding a horse is bumpy, as long as you master the skills and adjust your body according to the rhythm of the horse's up and down, it is not as uncomfortable as a carriage. Only people who don't know how to ride a horse sit stiffly in the saddle, and the bumps are uncomfortable.
When the three of Angela, mother and daughter drove back and forth from Aurich to Emden in a new carriage, Angela excitedly told Marin that she actually fell asleep comfortably in the carriage.
Marin actually didn't think so in his heart (Which time in my previous life did I not sleep on a long-distance bus?), but on the surface, he still showed a surprised expression according to Angela's expectations...
In fact, if it wasn't for Marin's safety considerations, he added steel plate protection on the outside to prevent assassination, and it would be no problem to use the convertible mode or use a wooden body to carry four strong men in the carriage.
Then, Marin asked the craftsmen to make several spring shock absorbers, which crashed into several other carriages. However, thicker shock absorbing springs are difficult to wind and process. During processing, even the most skilled craftsman is prone to scrap. Therefore, this kind of spring is destined not to be mass-produced.
Moreover, because the spring bearing capacity is limited, it cannot be applied to a wagon. Because the weight of the wagon carriage often exceeds 1.5 tons. Even if the shock absorbing spring is installed, it is easy to be crushed.
However, Marin made the shock-absorbing spring not for the purpose of transporting goods, but for the enjoyment of the nobles. As a result, all members of the Hoffman family got a shock-absorbing carriage for easy travel.
Then, the homes of the brothers Schwartz, Frundsberg, and Kahn Kohler, as well as Jeffrey and other important ministers of the country, also received shock-absorbing carriages rewarded by Marin.
For a while, the shock-absorbing carriage became the best choice for the nobles of the East Frisian Counties to travel. Because riding in a shock-absorbing carriage is too comfortable. Many noble family members began to ride in carriages, visit around, and even hold gatherings among wives. Of course, there is also the meaning of showing off your own carriage.
For example, some family members who received Marin's reward would often go to the home of good sisters who were not rewarded with shock-absorbing carriages, and invite them to ride in comfortable shock-absorbing carriages together. Then, I enjoyed looking at the envious and jealous eyes of my good sister.
The most important thing is that the shock-absorbing carriage cannot be imitated by others. Some blacksmiths did start to imitate Marin's shock absorbers and made springs. However, they are springs wound with ordinary iron, not even steel. Then, those fake shock-absorbing carriages worked fine the first few times, but after a few times of use, the springs deformed or broke directly, almost causing serious accidents. The deformed spring cannot continue to provide shock absorption. As a result, the copycat shock-absorbing carriages soon withdrew from the market one after another...
Marin's carriages are not only of good quality, but Marin also marked the maximum load capacity for each carriage. Because the maximum weight of the carriage cannot exceed 1.5 tons. Therefore, after each carriage is sent out, Marin will subtract the weight of the carriage from 1.5 tons, mark the maximum load in pounds, and warn the user not to overload, otherwise the shock absorber will have problems. Moreover, because the spring is not rust-proof, it usually needs more oil for protection. Once the spring is rusted, it needs to be replaced in time. Otherwise, the rusted spring steel is also easy to break...