1. Identifying the Role of Fullers: Fullers are forging tools that are almost always used in pairs—a top fuller and a bottom fuller. They are characterized by having
rounded working edges. Their primary engineering function is "fullering," which is the process of
necking down or reducing the cross-sectional area of a specific portion of the workpiece. This is achieved by creating grooves or indentations that displace the metal outward, thereby increasing the length while decreasing the thickness.
2. Functional Comparison with Other Tools:
• Swages: These are also used in pairs but have semi-cylindrical or shaped grooves. Their primary purpose is to finish or "swage" a piece to a specific round, square, or hexagonal shape, rather than just necking it down.
• Flatters: As the name implies, these have a flat face. They are used to smooth out surfaces and remove the marks left by fullers or hammers, ensuring the final forged part has a flat, even finish.
• Chisels: These are cutting tools used to part metal or cut off ends. They have a sharp wedge-like edge, which is fundamentally different from the rounded working edges required for fullering.
3. Summary of Use: Because fullers concentrate the force of the hammer blow to displace metal and reduce the cross-section precisely where needed, they are the standard tool for creating necks or reducing diameters in a forging operation.