Spinning

Spinning is an old process, in which a piece of sheet metal may be formed to shape around a rotating former, which is mounted on the spindle of a lathe. The necessary force to deform the sheet metal is generated by a long tool, which is levered about a suitably positioned fulcrum.

For thin gauge, soft metals, the tool can be manipulated by hand. While, for thicker gauge materials, a hydraulic actuator is used on a purpose-built machine. Cones, flares, bowls and bell-mouth shapes, are produced by spinning.