bar machine

lathe

Also known as: screw machine

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Last updated

June 18, 2026

Quick Summary

A lathe is a machine tool used to shape materials, typically by rotating a workpiece against a cutting tool. A specific type of lathe, known as a screw machine or turret lathe, is designed for high-volume production of small parts like screws and bolts.12

These machines often use bar stock, which are long metal rods, fed through a hollow spindle. Turret lathes have a multi-sided turret that holds various tools (like those for turning, drilling, and threading), allowing for quick tool changes and complex operations without skilled labor for each step. They can be classified as bar machines (formerly screw machines) for smaller parts or chucking machines for larger ones.132

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machine tool
Turret lathes
…may be classified as either bar machines or chucking machines. Bar machines formerly were called screw machines, and they may be either hand controlled or automatic. A bar machine is designed for machining small threaded parts, bushings, and other small parts that can be created from bar stock fed through…
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…may be classified as either bar machines or chucking machines. Bar machines formerly were called screw machines, and they may be either hand controlled or automatic. A bar machine is designed for machining small threaded parts, bushings, and other small parts that can be created from bar stock fed through…
Read More