The production of gears is a difficult project in this world.

Because in this world, there is no convenient and fast gear shaping machine, not even the simplest machine tool, and the machining of metal shapes can only be done by the blacksmiths' sledgehammers and hammers, or by casting the finished product with extremely rough quality.

With the help of homemade drawing instruments, Xia Lin quickly drew detailed drawings of the gearbox and internal gears, but after building the furnace and the dwarves began to cast according to the drawings he provided, the finished product did not meet his requirements at all.

"Master Holguin, these are white irons, they are hard and brittle, and there is no way to further process them into a gearbox, is there a way for you dwarves to turn them into a black malleable cast iron?"

After seeing the finished gear, Xia Lin was very happy to see that the finished product was not obviously deformed, but after tapping the edge of the gear with a small hammer, he saw that some iron filings were shattering, so he had to shake his head and ask Master Holguin.

"It turns out that what you want is black iron, not white iron, just say no earlier, wait for us to deal with it for a while!"

Master Holguin drunkenly took a sip of the fine ale that Charlin had offered, and soon the dwarves were quickly coating the cast white iron gears with a mixture of earth and grease of their own making, and once again placing the gears in the furnace and heating them up.

Xia Lin knew that this was annealing the white iron at high temperature, so that the carbon inside the white iron was precipitated in the form of graphite to improve the performance of the iron, and the perfectly annealed white iron would turn black, so that the cast iron had a certain toughness and could be roughly processed.

The dwarves' smelting skills really lived up to their reputation, and after a few hours, they made a fairly good quality black-hearted malleable cast iron gear.

This shows that the inside of this black-hearted malleable iron casting is also well annealed, and the structure is very fine.

He nodded in satisfaction, and after the dwarven craftsmen had polished the burrs and surfaces of the iron castings, they assembled a gearbox from the oiled gears, which looked black and shiny.

A wooden steering wheel is attached to the input shaft, and the output shaft is connected to the central shaft of a simple centrifuge taken from the family's small sugar workshop, and the gearbox is supported above the centrifuge by a wooden frame.

Then Xia Lin asked the two dwarves to stand on the stool and try to turn the steering wheel together, and in the difficult rotation, soon the simple centrifuge below was "whirring" and rotating, and the speed was at least several times higher than the original manual shaking.

According to Charlin's design, this gearbox with six gears has a transmission ratio of 1:16, which means that one rotation of the drive shaft can make the transmission shaft rotate 16 times, which is enough to support the work of a simple woodworking machine.

"Pryde, the Lord of the Molten Fire, what have I seen today?"

Seeing this strange scene, Master Holguin's drunken eyes widened suddenly, and his eyes glowed as he looked at the gearbox that had been born under the hands of his own people.

He was still disdainful of Xia Lin before, and the reason why he obeyed Xia Lin's request was only the inevitable bet on ten bottles of Wing Flame Dragon Blood Wine, but this gear gearbox made him change his mind slightly.

With a series of gears to change the speed, Master Holguin knew that such a machine had a lot of use in working with metal.

"Master Holguin, how's it going? These things are all made by your own hands, but they have nothing to do with the alchemist, but with this and the waterwheel that can be made in no time, we can drive the carpentry machines on those drawings to do the work.

When the time comes, you will have to drill a small hole in the iron with a bow drill for half a day, and my woodworking drill will not take a few minutes to achieve the same effect as you!

This is what I call the power of the new metalworking tool, the machine tool, and with it, you blacksmiths can be considered real blacksmiths! ”

Seeing that the effect of the gearbox was as he expected, Xia Lin showed a smug smile and said to Master Holguin with a fluttering eyebrow.

"Humph! Stinky boy, don't be complacent, I think this thing can be used for things like drilling small holes, but that's not what you and I said in the bet! ”

Although he was very concerned about this gearbox, in the face of Xia Lin's ridicule, Master Holguin still raised his head, and although he was short, he still said hard to Xia Lin.

"Naturally, there is not only one type of machine tool I am talking about, but other machine tools also have to rely on Master Holguin and the dwarven masters to make them!"

Xia Lin already knew this stubborn dwarven master well, and he said with a smile to the ten dwarven masters brought by Master Holguin on the side.

"No problem, you have enough wine, much more generous than the patriarch, not to mention that there are so many novelties, I have lived for so long, and I have never seen metal processed like this!"

Among the dwarven masters, a dwarf with bright fiery red hair patted his chest and said in a deep voice.

"Phew! Faun Molten! You traitor, it's not like I've worked so hard to raise you for so many years, where did you come from! You still call me stingy? I knew I wouldn't have saved you from the slave traders! ”

Master Holguin heard the dwarf praise Xia Lin and his words to slander him, and he immediately felt betrayed, and he shouted angrily.

"Hmph, with my Molten Fire Clan's skills, can't I be a human guest without you? At most, you're just one step ahead of me! ”

Farne Molten clasped his hands in front of his chest and looked at Holguin with disdain and said, the other dwarves were all submissive, but he dared to go toe-to-toe with Master Holguin, and it seemed that it was because of his molten clan name.

"You!"

Master Holguin was furious:

"Even if you are the priest clan of the Lord of Molten Fire, the forging skills of our Copperbeard Clan are not below you, I don't believe we can compare!"

"Compare to whom, who is afraid of whom? How many years have you not lost to me? ”

"That's right, I still have a very difficult novelty that you need to forge here, why don't you two use this thing to compare who is more powerful!"

Seeing that the two dwarven masters wanted to prove that their skills were more exquisite than each other, Xia Lin smiled and added fuel to the fire.

"What's that?" *2

Hearing that Xia Lin actually had something more difficult for them to forge, the two bearded and glaring dwarves turned their heads and said in unison.

"Bearing!"

Xia Lin took out the drawings he had already drawn and handed them to the two dwarven masters. One for each person, drawing detailed drawings of roller bearings and ball bearings.

Bearing is an indispensable part of the industry, and it is indispensable wherever the shaft needs to be used.

The bearing can reduce the transmission resistance, support the rotating body, speed up the starting speed, and ensure the rotation accuracy.

If there is no bearing, first of all, the shaft will be easy to wear, and secondly, the power transmitted through the shaft will lose a considerable part of the rotational wear.

The best effect in the bearing is naturally the ball bearing, but the world's precision machining effect of the ball is definitely not up to Xia Lin's requirements, so he also designed the roller bearing.

As for the ball bearing, it opened the eyes of the two dwarven masters and stimulated their research motivation.