The color of the steel rapidly cooled and darkened.

Lin Yu'an knew he only had a few tens of seconds of effective operation time.

When the color of the steel faded back to dark red, losing its optimal plasticity, he immediately stopped hammering.

Without any hesitation, his arm muscles tensed again, using the long handle to steadily lift the heavy steel rod and return it to the furnace once more.

But this time, his operation was completely different from before; he did not recklessly plunge the tip of the steel rod all the way into the depths of the furnace like the first time.

His eyes squinted slightly, peering through the gap in the operation opening, staring intently at the charcoal-built interior of the furnace while carefully adjusting the angle and depth of the long handle in his hand.

Then, he precisely positioned the part he had just hammered and initially flattened to stay in the "medium temperature zone" in the middle of the furnace.

Lin Yu'an said to the camera, "The core of forging lies in precise temperature zone management."

"The part that has already formed cannot withstand extreme high temperatures again, as it would cause excessive oxidation and decarburization on the steel's surface, making it brittle."

"At this time, placing it in the medium temperature zone allows it to slow down cooling, prevent stress cracks, and preheat the part that will be forged next, saving valuable fuel."

What he really needed to heat was the cylindrical section of the steel rod, right next to the flattened section, which had not yet deformed.

He pushed this small section forward, accurately sending it into the furnace's deepest part, the "high-temperature core zone" driven by the bellows, where the temperature was highest!

At this moment, under his control, this steel rod existed in a mysterious state inside the forge.

The flattened part at the front quietly "soaked" in the red glow of the medium temperature zone, maintaining its heat.

The heated section in the middle absorbed heat frantically in the incandescent light of the high-temperature zone, with its color changing dramatically to the naked eye.

Meanwhile, the larger portion of the rod remained exposed to the cold air outside the furnace, retaining its original gray-black color.

He began to blow air again, this time focusing all his attention intensely on observing the color of that small section of steel rod.

He could even feel the searing heat escaping through the furnace gap, making his cheeks hot.

When that small section reached a brilliant orange-yellow, he once again pulled the entire steel rod out and rushed to the stone anvil.

This time, he hammered not at the front end but at the area that had just been heated, right next to the flattened section.

"Clang! Clang! Clang!"

Using the edge of the axe's back, he skillfully transitioned the hammering, and under his heavy blows, the second section of the steel rod also flattened, perfectly connecting the new and old parts into a more integrated "steel billet."

He was like a skilled chef, precisely controlling the cooking temperature of different parts on a long iron plate.

With this complex operation of segmented heating, segmented forging, and front-end insulation, he managed to roll the hard steel rod from a cylindrical shape into a flat shape in an extremely fuel-efficient manner, bit by bit.

Lin Yu'an was deeply invested in this process; in his world, there was only the sound of the bellows breathing, the roar of the forge's flames, and the deafening booming of hammer striking steel.

Finally, after six rounds of laborious segmented heating and hammering, the foremost twenty centimeters of the steel rod completely transformed.

It was no longer circular but had successfully been forged into a gigantic fan-shaped flat "steel billet" over fifteen centimeters wide and less than a centimeter thick.

The first stage of flattening was finally complete.

He immediately placed the entire fan-shaped "steel billet" into the furnace for an overall heating session.

This was the largest heating area and the most charcoal-consuming session since the beginning. He had to ensure the entire "steel billet" reached the same temperature suitable for shaping.

When the giant steel billet turned an even orange-yellow, he withdrew it and began the more precise shaping of the second stage.

He placed the entire fan-shaped steel billet into the furnace for an overall heating session.

Then, he steadily placed the red-hot steel billet on the stone anvil.

He picked up a hand-made wooden hammer that was easy to grip for forging.

Holding the Forest Axe near the neck close to the axe head with his left hand for maximum control, he positioned the sharp axe blade like a hot chisel precisely vertical on the predetermined centerline of the steel billet.

Then, he raised the heavy wooden hammer with his right hand and struck hard at the back of the Forest Axe!

"Boom!"

A thud distinctly different from before echoed! The collision of the wooden hammer and steel was profound and solid.

Under the immense impact transmitted by the wooden hammer, the sharp blade of the axe instantly chiseled out a clear and deep incision on the scorching steel!

"Boom! Boom! Boom!"

He quickly moved the axe held in his left hand, continuously striking with the wooden hammer in his right along the predetermined centerline, "sculpting" all the way down.

When a straight, deep groove appeared perfectly in the center of the steel billet, he tossed the wooden hammer aside.

He gripped the Forest Axe again, hammering the metal on both sides of the groove outward.

Like a sculptor, he meticulously adjusted the angle and force of each strike, allowing the two "petals" to unfold at a perfectly symmetrical angle, forming two enormous "knife wings."

At the same time, he retained a small point of metal at the forefront, refraining from separating it. Instead, he used the edge of the axe's back to carefully hammer it into a sharp "guiding tip" resembling a spearhead for positioning.

A "shovel-shaped drill bit" prototype with a diameter over fifteen centimeters was born.

But this was not enough; a flat drill bit could only scrape and could not chip evacuate. It still needed a soul—a spiral.

For the eighth heating session, he evenly burned the fully formed drill bit to a dazzling orange-yellow once more.

This time, the operation location is no longer the stone anvil.

He quickly walked to the corner of the shelter, where there was a large wooden stake he had prepared, half-buried in the ground with great effort, and the base frozen with water.

The center of the stake had a deep hole pre-drilled by him.

He precisely inserted the guiding tip of the drill bit into the hole in the stake. The scorching metal touched the cold wood, emitting a "hiss" sound and a puff of burnt white smoke.

The drill bit was firmly fixed, with only the two giant fan-shaped "blade wings" exposed on the outside.

He took two lengths of water-soaked, one-and-a-half-meter-long sturdy birch sticks from the bucket.

Soaking them not only prevents them from being instantly ignited, but also creates a steam film upon contact with the scorching metal, serving as insulation.

He horizontally pressed the first stick from the front, firmly against the outer edge of one of the blade wings.

Then, he horizontally pressed the second stick from the back, firmly against the outer edge of the other blade wing.

At this moment, looking from above, the two sticks and the two blade wings of the drill bit created a cross structure like a windmill's blades.

"Hey!"

He let out a roar of exertion, channeling all his weight and strength into the two sticks, using the drill bit as the axis, and began a horizontal counterclockwise push-pull motion!

"Creak—groan—"

The two giant "blade wings," under his brute force, were no longer in the same plane but given a slight spiral angle sufficient to guide the ice shavings upward during rotation! 𝗳𝗿𝐞𝕖𝘄𝗲𝕓𝗻𝚘𝚟𝕖𝐥.𝚌𝕠𝕞

Shaping, complete!

He glanced at the dwindling charcoal and knew the most critical and error-intolerant stage of heat treatment had arrived.

He began the ninth and final key heating process after shaping.

"The next two steps, quenching and tempering, will determine the final fate of this piece of steel."

"Forging gave it shape, while heat treatment will give it soul. The conflicting properties of hardness and flexibility will reach their final balance in this baptism of ice and fire."

This time, he needed absolute precision in temperature control, the quintessential "fire-watching" skill of a blacksmith.

He smoothly placed the formed drill bit into the furnace, no longer vigorously blowing air, but instead rhythmically pushing and pulling the blower gently.

He waited, waiting for that perfect "phase change point" when the crystal structure inside the steel would begin to change.

Finally, the entire drill bit showed a uniform, not too deep, not too light, cherry-like red color.

"This is the temperature!"

He pulled out the drill bit without hesitation, turned and thrust it vertically into the nearby iron bucket filled with icy water!

"Sizzle—!!!"

A sound like boiling oil into cold ice erupted, accompanied by thick white steam, swallowing his entire being!

Quenching completed. The drill bit acquired unparalleled hardness but also became fragile like glass.

He carefully retrieved it from the water, the drill bit now turned gray-black, covered with a layer of fine oxide skin.

He used the natural whetstone Stan gifted him, with water, patiently and repeatedly polishing the edge of the drill bit's blade wings.

He wasn't "sharpening" but "polishing," removing the black oxide skin to reveal the shiny steel beneath.

Next, it was time to give this Ice Drill its final process—tempering.

He moved the remaining bit of charcoal to one side of the furnace, gently blowing with the bellows to form a lower temperature "afterheat zone."

Placing the quenched drill bit on the other side of the forge, exposing it only to weak radiant heat for extremely slow low-temperature heating.

He once again stared intently at the polished, silvery-white metal surface.

"Quenching elevates steel's hardness to its utmost, but the cost is destructive internal stress, making it extremely brittle."

"Tempering is a precise 'cooling down,' releasing a portion of stress through controlled low-temperature heating, trading a bit of hardness for crucial toughness."

"Judging the tempering temperature relies solely on the color of the oxide film forming on the steel surface."

Within minutes, a miraculous scene unfolded.

The silvery-white surface seemed alive, gradually and evenly "changing color."

First it acquired a very light yellow hue... then deepened to a mature straw-like yellow... followed by a hint of brown emerging, like a drop of coffee on white paper...

When the entire edge area acquired the brown color of toasted bread, he immediately pulled out the drill bit, setting it aside to cool naturally in the air.

Tempering completed. Looking at the primitive-shaped, hammer-marked drill bit with its beautifully tempered edge color, he knew he had succeeded.

At that moment, an indescribable, creation-like immense satisfaction filled his heart.

Glancing at the furnace, the charcoal inside had burned out, with only a bit of red embers left.

The fuel was just right.

————

(ps, the finished product is a larger version of this thing. This antique is worth 4 monthly tickets.)