Wednesday, 8 July 2020

What are the functions of Carriage in lathe machine?

The carriage of a lathe machine has several parts that serve to support, move and control the cutting tool. The carriage is consists of following parts.

  • Tool post
  • Tool post screw
  • Rocker
  • Concave ring
  • Tool
  • Compound rest swivel base
  • Cross feed screw
  • Binder screw
  • Cross slide
  • Cross slide nut
  • Saddle
  • Cross slide and wheel
  • Pinion on cross feed screw
  • Compound slide hand wheel
  • Compound slide feed screw
  • Compound slide nut
  • Compound rest

Carriage in lathe machine

Compound slide:

Compound slide or compound rest is mounted on the top of the cross slide and has a circular base graduated in degrees.

Compound slide is used for obtaining the angular type of cuts and short taper as well as convenient positioning of the tool to the work, by loosening two set screws that fit in a V-groove around the compound rest base.

The slide or rest may be swiveled to any angle with in a circle.

There is no power feed to the compound slide and it is hand operated. The compound slide handle is also equipped with a micrometer dial to assist in determining the depth of the cut. After setting the compound slide is locked solid with its base.

Cross slide:

The cross slide comprise a casting machined on the underside for attachment to the saddle and carries locations on the upper face for tool post.

In order to moves the cross slide the feed screw is turned by rotating the hand wheel. The transverse movement is obtained when the nut is mounted on the feed screw is engaged with the binder screw of the cross slide.

Whenever the taper turning attachment is used the binder screw is opened to disconnect the cross slide from the cross feed screw. Usually the cross slide hand wheels are graduated on their rims or a separate micrometer.


 The saddle is an H-shaped casting it fits over the bed and slides along the ways. It carries the cross slide and tool post. Some means are keys type generally provided for locking the saddle to prevent any movement when surfacing operations are carried out.