Using an old, worn-out cast iron skillet to make a decent sword is not a practical or recommended approach. Cast iron skillets are not suitable for sword-making for several reasons:
Material Properties: Cast iron is brittle and not well-suited for making swords. It lacks the necessary flexibility and tensile strength required for a functional blade. Swords need to be able to withstand impact and stress without breaking or deforming easily, which cast iron cannot provide.
Melting and Forging: Melting down a cast iron skillet would require an extremely high temperature, far beyond what most people can achieve in a typical household setting. Even if you could melt it, forging a sword from cast iron would likely result in a poor-quality blade with numerous defects.
Alloy Composition: Cast iron is not a homogenous material; it contains various impurities, such as carbon, silicon, and sulfur. These impurities can negatively affect the blade's performance and make it unsuitable for use as a sword.
Heat Treatment: Crafting a functional sword requires precise heat treatment processes to achieve the desired hardness, toughness, and edge retention. Cast iron does not respond well to these heat treatment techniques and would not result in a useful blade.
If you're interested in making a sword or acquiring one, it's best to consult with a professional blacksmith or a reputable swordsmith who can work with appropriate materials and techniques to create a safe and functional sword. Modern steel alloys are commonly used for sword-making due to their excellent balance of hardness and flexibility, making them much more suitable than cast iron.