Page:Turninglathes.djvu/14

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TURNING LATHES.




CHAPTER I.

DESCRIPTION OF THE LATHE.

The novice who has never examined a Lathe, but, having seen others using it, thinks he should also like to try his hand at the work, naturally wants to know its construction. He hears of chucks, and mandrels, and poppets, but the terms convey to his mind nothing but mystery. We shall, therefore, at once enlighten him. Beginning at the stand, he will see two cast-iron uprights, supporting between them parallel bars, nicely planed. These are called the standards, and are sometimes, but not very generally, made of wood. The parallel bars are called the bed, sometimes gantry, which appears to be an American coinage, not very expressive, and decidedly ugly. Half-way between the bed and the floor, the crank axle is suspended, generally upon centres or pointed steel screws; but sometimes this axle runs in brasses, called bearings or bushes, and sometimes it rests upon small turned wheels, called friction wheels, which are supposed to give it an easier motion. At the lowest part is hung a treadle for the foot, and this is connected to the crank by an iron hook, or by crank chain passing over a roller in the treadle bar. This gives a smooth rolling motion. Sometimes the crank hook is called the pitman.