Carbon is fired at extreme heat to create the steel that’s needed to make a sword, but the swordsmith has to understand how much of that carbon to use to get the result they want. The firing of the metal is something that takes a lot of time, and it has to be done by someone with a skilled hand. You see, there’s more to a sword if you get deeper into the process.
The sword is being formed using as much carbon as the swordsmith needs, but they’ve to remember that the blade attaches to a handle. That means that they’ve to add other components that’ll help the sword attach to the handle correctly.
Japanese swordsmiths use iron sand, and it’s fashioned with an iron stone. The stones help to make the shape, and that makes it much easier for the swordsmith to get the results that they want. Those who don’t use the iron sand and stone will do the shaping with a hammer of varying sizes. They can actually get the metal to be very thin, but they’ve to have used enough carbon before they started thinning out the metal.
The sword has to be heated and cooled many times before it’s ready to be finished. This means that it’s heated and cooled many times to get the temperature to drop until it’s the right temperature to handle for finishing. It doesn’t have to be blazing hot to be finished, but it does have to be set up to be finished by settling down to a temperature so that it can be managed. Letting it cool all at once will likely make it break.
As for the finish, most can finish with a water stone, but it can also be done with a smaller sharpening stone that’s used by hand. The water stone is very large, and it’s used to help cover the whole blade at once. The whole blade can be one even shape, or someone can move the stone across the blade by hand. Both styles are accepted, but it depends on the swordsmith.
Others will make the hilt, attach the hilt, or even put the engraving on the blade. Dipping it in a lacquer to get a silver or gold color is also done by another professional artisan until the sword looks perfect.