Introduction

INTRODUCTION
A turning operation is an operation in which a rotating work piece is turned against a cutting tool so that required amount of material (chip) can be removed from the work piece to give the required shape and size



CLASSIFICATION
1st Classification i) Bench type and Floor type

2nd classification : i) manual type ,

ii) CNC type

ASSEMBLIES AND COMPONENTS


HEADSTOCK
Located at the left hand size of a lathe machine houses spindle
The spindle is driven by an electric motor through a system of belt drives and/or gear trains.
Spindle speed is controlled by varying the geometry of the drive train. (which is achieved by turning the gear level into a desired position).
Various work holding attachments such as three jaw chucks, collets, and centers can be held in the spindle
CARRIAGE
The carriage supports the cutting tool and also move the cutting tool . It consists of:
A saddle that mates with and slides along the ways.
An apron that controls the feed mechanisms.
A cross slide that controls transverse motion of the tool (toward or away from the operator).
A tool compound that adjusts to permit angular tool movement.
A tool post T-slot that holds the tool post.
TAILSTOCK
The tailstock can be used to support the end of the work piece with a center, or to hold tools for drilling, reaming, threading, or cutting tapers. It can be adjusted in position along the ways to accommodate different length work pieces. The ram can be fed along the axis of rotation with the tailstock hand wheel.

CUTTING TOOL TERMINOLOGY

Facing tools are ground to provide clearance with a center.
Roughing tools have a small side relief angle to leave more material to support the cutting edge during deep cuts.
Finishing tools have a more rounded nose to provide a finer finish. Round nose tools are for lighter turning. They have no back or side rake to permit cutting in either direction.
Left hand cutting tools are designed to cut best when traveling from left to right.
Aluminum is cut best by specially shaped cutting tools (not shown)that are used with the cutting edge slightly above center to reduce chatter.