Ever notice that chandelier hanging from the ceiling or that metal bowl in your kitchen? Chances are that those items were manufactured through a process called metal spinning. The metal spinning process, also known as spin forming, is a cold metalworking process. In some ways, metal spinning is similar to other turning processes and can involve equipment similar to screw machine products, which historically have been made to manufacture fasteners, or lathes, which can be used for many purposes. These processes differ from other types of metalworking because they are performed at or near room temperature. Hot metalworking process is done at the recrystallization point that could cause the metal to oxidize and drastically change the metal’s properties.
Metal spinning can be done manually or it can be automated with the use of CNC machinery. Manual metal spinning requires a highly skilled technician to operate the lathe. A flat metal disc, also referred to as a blank, is affixed to a lathe mandrel and rotated at an rpm. The metal is then shaped with hand-held tools as the metal spinner technician applies pressure to the blank. In the end, there should be little to no metal waste and no wrinkling and both the interior and exterior surface of the product should be smooth and shiny.
Generally, metal spinning is a cost-effective choice for companies. It is typically used for smaller runs. Metal spinning produces hollow, symmetrical shapes maintaining a wall thickness throughout the piece. Metal spinning processes like hydroforming and shear spinning provide alternative ways to shape metal with a cold metalworking process.
Metals that can be used for metal spinning include steel, stainless steel, aluminum, copper and titanium, as well as alloys of the previously mentioned metals. Metal spinning adds to the excellent characteristics of these metals and alloys such as their hardness, strength and durability. Metal spinning is used across many industries including medical, pharmaceutical, aerospace, military, aviation and chemical. Metal spinning is used to make tank heads and other material containment parts, bicycle parts, bodies for cars, kitchenware among others.