Screw-cutting Lathe - Present Day

Present Day

Until the early 19th century, the notion of a screw-cutting lathe stood in contrast to the notion of a regular lathe, which lacked the parts needed to guide the cutting tool in the precise path needed to produce an accurate thread. Since the early 19th century, it has been common practice to build these parts into any general-purpose metalworking lathe; thus, the distinction between "regular lathe" and "screw-cutting lathe" does not apply to the classification of modern lathes. Instead, there are other categories, some of which bundle single-point screw-cutting capability among other capabilities (for example, regular lathes, toolroom lathes, and CNC lathes), and some of which omit single-point screw-cutting capability as irrelevant to the machines' intended purposes (for example, speed lathes and turret lathes).

Today the threads of threaded fasteners (such as machine screws, wood screws, wallboard screws, and sheetmetal screws) are usually not cut via single-point screw-cutting; instead most are generated by other, faster processes, such as thread forming and rolling and cutting with die heads. The latter processes are the ones employed in modern screw machines. These machines, although they are lathes specialized for making screws, are not screw-cutting lathes in the sense of employing single-point screw-cutting.

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