Half an hour later, the two of them came back with a piece of wood with a diameter of more than 40 centimeters and a length of more than two meters.

According to Chen Xu's design, the biggest problem with this simplest hand-crank threshing machine is its stability during rotation, which must ensure that it will not be stuck by wheat grass after rotation. Therefore, the kinetic energy required when the spindle rotates is very high, that is, it must be very heavy. After rotation, it can rotate at a high speed under the rotation kinetic energy of the spindle itself to smash the shell of the wheat ears. The faster the rotor speed, the easier and cleaner the threshing will be.

Chen Xu asked Niu Dashi to first choose the straightest place on the wood he lifted back to saw a piece of wooden stake about 80 cm long, then used a hatchet to scrape the bark outside, and then used a chisel to dig a small hole two inches deep on it at about three inches away. The positions of the holes were all staggered. After the holes were dug, a few old bamboos were cut into five-inch-long bamboo nails, which were thicker than the hole, and then nailed them into the hole one by one.

Actually, Chen Xu had never done Mufu before. He just saw a carpenter making doors, windows, tables and chairs when he was a child, but after traveling over, he found that he was the best carpenter in the village.

When he was repairing the house, the rough tenons he designed and made according to his copy were recognized by the whole village, and he agreed that the tenons not only accelerated the speed of building the frame of the house, but also enhanced the safety of the house.

For example, the simplest double concave connecting tenon is common in later generations, but the villagers were as surprised as if they discovered a new world. They unanimously decided to use tenons to rivet the house in their homes in the future.

Later, when Chen Xu asked, he found out that now the villagers should go up the mountain to choose trees that happen to be in the right place with branches, otherwise the beams would not be able to be built.

As a house was built, Chen Xu's wooden work became better and better, and he used knife, chisel, axe and saw in a good manner. Although he was definitely the most miserable carpenter in later generations, he is now the best wooden worker among the army.

Just as Niu Dashi was treating the central rotation shaft of the threshing machine, Chen Xu also built a simple wooden frame with a few pieces of wood as thick as a calf, one meter high and one meter wide. He used an axe to cut out a U-shaped bracket on both sides to place the threshing spindle that Niu Dashi was making.

Then there is the main hopper, which must be sealed with wooden boards. Chen Xu calculated that about a dozen wooden boards were needed, so he could only pick up the copper saw again and start sawing the wooden boards.

A day passed by in a flash.

It was not until the sun was about to set that Chen Jiang came back from the river beach with Xing'er. Chen Jiang jumped in a load of vine basket, and Xing'er carried a basket of pig grass.

In the setting sun, a strange wooden box is placed in front of the house.

Chen Xu and Niu Dashi were busy surrounding the wooden box with sweat on their heads, and there was also a huge wood covered with bamboo nails inside.

"Brother, what is this?" Xing'er asked in surprise.

"This is the threshing machine we made!" Niu Dashi replied excitedly.

"What is the threshing machine for?" Xing'er's eyes widened.

"It is used to harvest wheat. With it, you don't have to get the ears back and dry them. You can peel the wheat out in the field." Niu Dashi said with a rosy look.

"Oh, that's great! Mom~ Mom~, come and see, my brother has made a threshing machine, and we no longer have to pick wheat ears back to dry it!" Although Xing'er seemed to understand, she still shouted loudly.

Chen Jiangshi said while making a fire and cooking: "Don't disturb my brother and Brother Dashi's work, hurry up and feed the pigs, and make tea for my brother after feeding water!"

"Hey~" Xing'er agreed and went to feed the pigs quickly.

Chen Jiang's mind is simple and direct. Now she feels it is natural no matter what her son does, because her son has become the most popular person in the village. Now, no matter where he goes in the village, he will happily praise Chen Xu, which makes her feel sweet.

She also heard what Niu Dashi said just now.

Therefore, her heart was full of expectations.

How did this strange-looking wooden box take off the wheat grains?

"Come on, lift the spindle down, it's almost like that. Install the spindle and you can rotate and test it." Chen Xu continued to observe and measure and then hit several places with an axe a few times. It felt almost the same, so the two of them lifted the huge spindle that was 50 or 60 kilograms down.

Next, a square large hole with a side length of fifteen centimeters must be made at the center of both sides of the spindle, and this hole is used to install the shaft. In order to ensure that the hole must be in the center of the spindle, Chen Xu used a bamboo ruler he made to measure repeatedly for a long time before drawing a box with a fine charcoal.

Niu Dashi has always been a passive help. He couldn't understand anything about the spindle, spindle, hopper, crankshaft, and crankshaft, but going without hindering him from showing enough interest in this magical thing.

It was so amazing that he didn't know where his brother-in-law learned these incredible things.

The square hole must be completely vertical to prevent the center of gravity from jumping unsteadily when the spindle rotates. Chen Xu was worried about letting Niu Dashi do this, so he had to do it himself.

In order for the threshing machine to be strong enough, the square holes on both sides were nearly twenty centimeters, so it was not until Chen Jiang finished the supper that the two square holes were just finished.

After dinner and having tea and resting for a while, Chen Xu began to make the spindle again, using two rosewoods as thick as calves, one end was cut into a square shape, and the other end was trimmed into a perfect cylinder with a knife and axe. Carefully nailing the square head into the square holes at both ends of the spindle.

"Huh, fortunately, the spindle did not crack!" When both spindles were nailed in, Chen Xu couldn't help but breathe a long sigh.

The spindle and hopper are completed, and even if the threshing machine is completed, the last step is to install the shaker.

First, saw a convex tenon at the cylindrical end of the long spindle, then rivet a square hole of the L-shaped wood specially sawed back, then punched it into a bamboo nail and stuck it. Finally, tie it with a hemp rope to three or four layers, and tie the junction of the shaking handle and the rotary shaft tenon like a rice dumpling, so that the thinnest and most stressed parts will not be broken too hard.

In fact, the joint parts of the spindle and the hopper, as well as the tenon and rivet parts of the shaking handle should be made of metal, so that it will be more wear-resistant. Unfortunately, there is no such condition at present, so it is too late to build it in the town.

"Come on, let's try it!" Chen Xu threw down the hemp rope in his hand.

"Brother Xu, is that good?" Niu Dashi was very excited. His eyes, who had been standing by the side just now, were full of infinite admiration for his brother-in-law to make such complex things with tenons.

"Well, put it on and turn it to see the effect!" Chen Xu nodded, and the two of them lifted the spindle equipped with the rotary shaft and handle onto the bracket of the hopper.

"Click~"

As the spindle is firmly rested on the U-shaped bracket, the gap between the spindle is less than one centimeter from both sides of the bracket, which is completely within Chen Xu's design range. If it were done by a real carpenter in later generations, the gap between the two sides would not exceed two millimeters. But under this condition, this gap is perfect with Chen Xu, a half-baked carpenter.
Chapter completed!