Chapter 173: New weights and measures

Da Vinci was very serious about working. As one of the best mechanical engineers in the contemporary world, Da Vinci is also very proficient in mechanical manufacturing. Although Da Vinci is not very proficient in the manufacture of clockwork, it does not mean he will not.
马 In the strong crowd of Marin, Da Vinci showed how to create gears and clockwork ...
But to Marin's surprise, Da Vinci not only made the gears and clockwork completely by hand (nonsense, where is a machine tool for him?), But also did not use high-precision measuring instruments.
For example, when building gears, Da Vinci first calculated the size, and then roughly measured the mold and cast the billet. Then, holding the blank, began to sand manually. Grind for a while, then come up with a "standard" reference for physical comparison. After the comparison, if there is no problem, directly put it into use. If there is a problem, continue to grind ... If it is worn, it is smaller than the standard reference size, and it will be scrapped directly ...
Marlin looked a little blank:
"Ada, didn't you calculate the size in advance? Why did you grind it?"
"What's the use of calculation? The error is still too big ..."
Then, through Da Vinci's explanation, Marin learned that in this era, the smallest unit of length in Europe turned out to be inches ...
Moreover, Europe does not currently have a vernier caliper in the modern sense, only Britain has a vernier caliper similar to a vernier caliper. Of course, because this caliper scale does not have a precise scale, the measurement is not very reliable.
It is logical to say that manufacturing gears and clockwork should be considered as very precise devices, which require very precise specifications and graduations. However, in this era, when manufacturing precision parts, the unit that can be accurately measured is only about one-tenth of an inch, and the accuracy is less than 1 millimeter. Therefore, when Marin watched Da Vinci making gears and clockwork, he often saw Da Vinci rework and grind again. Because the previous calculation is not bad, but because of the large measurement error, parts mismatches often occur and need to be reground. Once worn too much, parts have to be scrapped.
In this era, the difference between the great craftsman and the apprentice, in addition to knowledge, is in the grinding process. For example, a large craftsman is good at grinding parts. At the stage close to the scale, he will be very careful, so that there are few parts to be scrapped and the yield is high. And those apprentices often arrive at a critical moment when the control is not good and the parts are scrapped. Even if it is not scrapped, because of poor manual control, the running-in between parts is not good.
Moreover, it is also very difficult to check the quality of the workpiece in this era. It is necessary to take out the "standard" workpiece to carefully check the sunlight and test the eyesight.
Unlike the later generations, the parts are all sized. As long as the quality inspector holds a vernier caliper in hand, he can see how big the error is. Then check the table to see if it is within the allowable error range, and then you can determine whether the workpiece is qualified ...
"If only a vernier caliper is available!" Marin said with emotion.
However, before making the vernier calipers, Marin had to get the weights and measures first.
Because there are no centimeters and millimeters in this era, Marin needs to define it himself. Moreover, the vernier calipers are very precise, and the lowest scale of ordinary vernier calipers has reached the level of 0.1 mm. Basically, 0.1 mm vernier calipers are absolutely sufficient in this era. Even at the industrial level of the 19th century, this scale was sufficient.
However, because meters, decimeters, centimeters, and millimeters are not yet available. Therefore, Marin first needs to
create
such weights and measures himself.
But for European metrology, Marin is most familiar with English units. For example, one inch = 2.54 centimeters. And weight, one inch pound = 453.59 grams ...
So, to infer how long a standard centimeter is, just figure out how long a standard inch is. Then, based on the principle of 1 inch = 2.54 centimeters, we can quickly find out how long is 1 centimeter. Then every 1 / 10th of a centimeter is 1mm ...
At the same time, 1 standard British pound is equal to 453.59 grams. So, as long as you get the standard weight of 1 inch (all countries generally cast copper weight as the standard weight reference), you can reverse that 1 gram is a variety of ...
For this reason, Marin sent someone to the United Kingdom to find a way to contact the British court, obtained the standard feet, inches and imperial pounds of data, and brought them back to Den Burg.
Then, under the surprised gaze of Da Vinci, Marin inferred lengths of 1 cm, 1 dm, 1 m, and 1 mm. Then, even more imperial pounds, inferred the weight in grams and kilograms.
Later, Marin arranged artisans to create standard reference copper rulers of 1 meter and 1 decimeter with copper, and used copper to create standard 50g, 500g, and 1000g copper weights as a standard reference for weight . After making reference materials, these standard items were sealed and wrapped in paper. Only take it out for comparison and use when needed.
After setting the weights and measures, Marin began to ask Da Vinci to help create a vernier caliper. Then, Da Vinci with good craftsmanship, under Marin's theory, created a very standard copper vernier caliper, and the scale used is also accurate to 1 mm. Although it does not reach 0.1 mm, it is quite sufficient. Because in the era of hand-made devices, 1 millimeter is already a very precise scale. As for the error, the experienced craftsman actually felt it.
With vernier calipers, Da Vinci made gears and clockwork much easier. For example, when turning gears in foundry casting, there is no need to take out a standard reference, but you can directly make the mold according to the standard size, and then start casting ...
Marin also told Da Vinci that the vernier caliper can actually be accurate to 0.1 mm, but because of the manufacturing process, it is difficult to produce a vernier caliper with an accuracy of 0.1 mm. Of course, with Da Vinci's technology, if you spend more time and scrap a few more, you can also make vernier calipers accurate to 0.1 mm.
I heard that Marin said that Da Vinci was also interested. So he paused other tasks and focused on making vernier calipers. Finally, after scrapping dozens of them, three relatively standard copper vernier calipers were made.
With such a high accuracy vernier caliper, Da Vinci himself felt that when manufacturing gears and clockwork steel wheels, it was much simpler. Previously, for the quality of gears and springs, Da Vinci needed to come up with real objects for repeated comparisons. Now, if you want to know whether the size is standard, just take out a vernier caliper card and measure it, then you can easily get it. In this way, Da Vinci, who was originally not good at making clockwork, also made a standard clockwork.
Of course, just the appearance standard. As for quality, Da Vinci admits that standard clockwork steel wheels are made from refined steel that is repeatedly forged by excellent blacksmiths. This steel wheel made by Da Vinci is simply made of wrought iron provided by Marin. Although the size is very standard, the internal stress is not correct and needs to be adjusted.
However, for the marlin, he knows that it is best to use spring steel with the most elasticity. The simplest spring steel is actually a kind of tool steel (high carbon steel). The repeatedly forged steel bar is actually the blacksmith's repeated heating and forging, which reduces the carbon content of pig iron and becomes high-carbon steel.
Therefore, for steel bars that seemed difficult to process in the Middle Ages, Marin knew that it was actually easy to manufacture, as long as the carbon content of the steel was kept at 0.62 ~ 0.90% (which is the lowest carbon content of high-carbon steels, close to Medium carbon steel level), add a little manganese (content is about 1%, specifically 0.90 ~ 1.20%, but in actual control, it is not so precise, as long as it can be used), and then after a simple heat treatment, the lowest in future generations is obtained Grade spring steel-65Mn steel.
With the 65Mn steel, the quality should not be much better than the steel bars that are now forged many times by pig iron masters. Moreover, because it does not need to spend so much labor to repeatedly forge processing, costs and man-hours can be greatly reduced.
In fact, many steel knives in ancient China used a similar method of "thousands of hammers and smelts" to repeatedly heat and forge a piece of pig iron to reduce and consume the internal carbon content. Finally, steel, also known as "bailian" steel". The so-called refined iron is actually obtained in this way.
However, through scientific methods, Marin can directly turn pig iron or wrought iron into steel, which saves the step of repeated forging ~ EbookFREE.me ~, which not only saves man-hours but also greatly reduces costs. Moreover, the quality of the two is similar.
Of course, to get qualified 65Mn steel, Marin also needs some time and the help of some craftsmen. However, since Marin is the technical guide of this traversor, it is only a matter of time before 65Mn steel is produced.
65 Once the 65Mn steel is produced, the clockwork production does not require the blacksmith master to repeatedly heat and forge, and it takes a lot of energy and fuel to process the pig iron into steel bars. By then, the production costs of spring steel wheels, chains and springs will be greatly reduced.
What's more, if the production cost of these components is reduced, then the production cost of the revolving rifle, which was originally expensive, can be reduced a lot. In this way, it also greatly facilitates the mass production and installation of revolving guns.
Uh ...
Because of the improvement of weights and measures and the advent of vernier calipers, Da Vinci found that it is much easier to process spring steel wheels, chains or springs. As long as the size and location of the part with the best attributes are kept in mind, and the amount of the upstream caliper is put, you can accurately determine whether the part is qualified. Then, according to the standard requirements, let the artisan make a slight adjustment. In this way, the production of precision parts is much more convenient ...
The only trouble is that Da Vinci seems to be a little uncomfortable with the new weights and measures. Even if the value is measured, I always unconsciously convert the old size in my heart. However, Marin believes that standard decimal weights and measures like this one, which are popular in later generations, are much more convenient than old weights and measures, whether it is calculation or memory. As long as you use it for a long time, you will find it more convenient and practical than the old-fashioned weights and measures ~ EbookFREE.me ~ Welcome the book readers to read, the latest, fastest and hottest serial works are all in ~ EbookFREE.me ~ Mobile users Please read it.