Spinning Metal

—The proce of forming circular articles, many of which are used for electrical purposes, from soft ductile sheet metal by pre ure on the circumference while they are revolving in a lathe. A wooden chuck or mould of the interior surface is attached to the fast headstock, while the sheet of metal is pinched between the chuck and the loose headstock. As mould and metal revolve, presure is applied to the latter, means of various tools and burnishers. whic cause the metal to conform to the shape of the mould. The latter is often made up of concentric pieces fitting into one another, which may be drawn out one by one, as required by the progre of the manufacture.