A metalworking lathe is one of the power houses of the trade. This stationary power tool can turn at speeds near 1800 rpm. First, a round stock of material is mounted in the lathe. The stock is larger in diameter and in length than the final part. The stock rotates at high speed while a cutting tool is controlled by the machinist. Movement of this cutting tool can be controlled to thousandths of an inch. The cutting tool is made from a material called “tool steel”. Tool steel has a higher hardness than the stock of material. Lubrication is added to reduce heat and maintain a smooth cut.
A lathe part must be axis-symmetric. For sections of the part which are not axis-symmetric, the part must be removed and machined with other tools of the trade. Special techniques allow the machinist to knurl a part to provide a grip or a handle. Additional techniques allow a part to be threaded such as a bolt.
Great article.