Once you have prepared your forge, take a long piece of steel and heat it up. If you are …show more content…
Vermiculity is a saw dust like material that is popular amongst blacksmiths for cooling metal. The name comes from the look of the material which resembles vermicelli pasta. Once your blade is successfully cooled, you can begin coating your Katana with clay. The clay used to coat samurai swords is a mixture of red pottery clay, sodium hydroxide and some water. This is ground down and painted on fifty percent of the blade's surface. Put on a coat of no more than two millimeters and make sure not to trap in any air bubbles or dents. Once coated, heat the blade until the sword has a low red glow. Make sure you don't overheat the Katana at this step. If you have trouble seeing the red glow then dim the lights or use a dark bucket.
The clay coat allows the blade to be further cooled at two different speeds. The uncoated part will cool faster making it harder. The process is called martensite and happens when steel, which is made from iron and carbon, changes temperatures rapidly. Martensite is how Katanas get their curve. Repeat the process to get an even meaner curve on your