Parts of a Lathe Machine – Engine Lathe and Its Carriage

All 19 parts on the diagram

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The whole lathe 12

Headstock It holds the spindle and the gears that set its speed.
Tailstock It supports the free end of the work. It slides along the ways.
Bed The foundation of the lathe. Every other part is mounted on it.
Chuck It grips the work and turns with the spindle.
Carriage It carries the cutting tool and moves it along the bed.
Spindle The shaft that turns the work. A hole runs through its whole length.
Chuck jaws They close on the work and hold it.
Ways The carriage and the tailstock slide along them.
Lead screw It moves the carriage when the half nuts close on it. This cuts a thread.
Quick-change gearbox Its levers set the thread pitch. They replace a set of loose change gears.
Tailstock center A pointed center that supports the end of the work.
Tailstock handwheel Turning it moves the spindle of the tailstock in and out.

The carriage 7

Saddle It sits across the ways. It carries the cross slide and the compound rest.
Apron The front of the carriage. It holds the feed gears and their controls.
Carriage handwheel Turn it to move the carriage along the bed by hand.
Half-nut lever It closes the half nuts on the lead screw for thread cutting.
Cross slide It moves the tool across the bed, toward the operator or away.
Compound rest It sits on the cross slide. It can be swung and clamped at any angle.
Tool post It clamps the cutting tool.

How this list was compiled: Every name checked on 2026-09-30 and kept only where at least two of these use it. (1) US Army, TC 9-524 Fundamentals of Machine Tools (1996), chapter 7, full text at https://archive.org/details/tc-9-524-fundamentals-of-machine-tools-1996 : the bed and its ways; the headstock and main spindle, with a hole through its length; chucks on the spindle; the tailstock, clamped anywhere along the ways, its sliding spindle worked by a hand wheel, the tailstock center; the carriage, which includes the apron, saddle, compound rest, cross slide and tool post; the compound rest swivelled and clamped at any angle; the half-nut lever and handwheel on the apron; the quick-change gearbox; the lead screw. (2) A lathe maker's Manual of Lathe Operation and Machinists Tables (1937), full text at https://archive.org/details/lathe_operation_and_machinists_tables_1937 : headstock, spindle, bed ways, carriage, the apron as the front of the carriage holding the power feed mechanism, the carriage hand wheel on the front of the apron, cross slide, compound rest, tool post, half nuts and their lever, lead screw, gear box, tailstock, tailstock center and tailstock hand wheel. (3) Wikipedia, Metal lathe and Lathe, https://en.wikipedia.org/wiki/Metal_lathe and https://en.wikipedia.org/wiki/Lathe : bed, headstock, spindle, chuck and jaws, carriage (saddle and apron), handwheel, cross-slide, compound rest, toolpost, leadscrew and half nut, quick change gearbox in place of change gears, tailstock, dead center. Licence: own work

The drawing: Drawn for this site on 2026-09-30 from plain geometry; no maker's machine, nothing traced. Licence: own work

How it works

A manual metalworking lathe, the engine lathe of a machine shop, seen from the front. The second drawing enlarges the carriage: saddle, apron, cross slide, compound rest and tool post.

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From headstock to tailstock

The headstock at the left turns the spindle, and the chuck on the spindle grips the work. The tailstock at the right slides along the ways, and its center supports the far end of a long piece. Between them the carriage carries the cutting tool along the bed.

What the carriage is made of

The saddle sits across the ways. On it the cross slide moves the tool across the bed, and the compound rest above can be set at an angle. The tool post clamps the tool. The apron hangs at the front with the carriage handwheel and the half-nut lever.

On a wood lathe the turner braces a hand tool on a tool rest. This machine clamps the tool in a tool post.

Questions and answers

What are the main parts of a lathe machine?

The bed with its ways, the headstock with the spindle and chuck, the tailstock, and the carriage. The carriage is made up of the saddle, apron, cross slide, compound rest and tool post. A lead screw runs along the front of the bed.

What are the parts of a metal lathe that move the tool?

The carriage moves the tool along the bed, the cross slide moves it across the bed, and the compound rest moves it at whatever angle it is clamped to. The tool post on top holds the tool.

What does the lead screw do on a lathe?

It is a long threaded rod along the front of the bed. When the half-nut lever closes the half nuts on it, the turning screw moves the carriage along, which is how a thread is cut.

What is the tailstock for?

Its center supports the end of a piece turned between centers or a long piece held in the chuck. It also holds tools such as drills and reamers. It can be clamped at any point along the ways.