LARGEST diameter of work that can be carried between the centers of a lathe is known as swing.The size of a lathe is generally specified by the following means:Distance between centres - Maximum length of the job that can be held between head stock and tailstock centresSwing over the bed – Maximum diameter that can be rotated over the bed waysSwing over the cross slide – Largest diameter of the work that will revolve over the lathe saddleSwing or maximum diameter that can be rotated over the bed waysBed length, which may INCLUDE head stock length alsoMaximum diameter of the bar that can PASS through spindle or collet chuck of capstan latheMaximum swing over bedMaximum swing over carriageHeight of centrers over bed Saddle: The saddle is mounted DIRECTLY on the top of the base. It carries the table and traverse CROSSWISE to the table movement.