What is metal spinning?
Metal spinning is the process of forming a piece of flat metal
in sheet stock over a pre-turned, three-dimensional pattern
while it is spinning on a machine tool similar to a lathe. The
forming is accomplished by applying pressure to the metal as
it spins thus forcing it against the form and causing the metal
to take the shape of the form. Metal spinning is most commonly
used for open forms; meaning that the opening diameter is larger
than the rest of the form, thus allowing the spun metal to be
easily removed from the pattern. When closed forms are required,
it is possible to form the component as multiple pieces and
then solder them together to form the final closed spun form.
Metals ideal for spinning include aluminum, copper, brass, pewter,
bronze, silver and mild steel in gauges from 22 (.025")
to 14 (.064"). The metals should be annealed prior to beginning
the spinning process. If the process it geometry has drastic
changes along the form, it may even be necessary to anneal the
metal a second or third time before the spinning can be completed.
Metal spinning is often performed under CNC control this is
referred to as CNC metal spinning.
Metal
Spinning 
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