Factors Governing the General Shape of a Turning Tool and the Contour of its Cutting Edge: The most important points in any turning tool are: (a) The cutting edge of the tool must have a certain shape or contour. Some turning tools have straight rounded corners as at (i) (ii) and (iii) of Fig. 12.100, whereas others have curved edges [...]
The power flows from the motor in the base to the cone-pulley by means of a belt. The belt can be adjusted to three or four positions to vary the spindle-speed. Fig. 12.15 gives the idea as to how the different spindle speeds can be obtained. Various spindle speeds can be obtained by shifting the belt on different steps of [...]
The following points highlight the five main applications of lathe used in the industries. The applications are: 1. Forming 2. Contour Turning 3. Machining of Cams 4. Ultra Precision Machining 5. Hard Turning. Application # 1. Forming: Forming is the operation of producing profile on a lathe using a special form tool which bears the reverse of the required profile [...]
In this article we will discuss about:- 1. Cutting Forces of Lathe 2. Cutting Speed 3. Feed 4. Depth of Cut 5. Turning Problems. Cutting Forces of Lathe: The cutting forces depend upon several factors like work material, cutting speed, feed rate, depth of cut, approach angle, side rake angle, back rake angle, nose radius and tool wear. The influence [...]
In this article we will discuss about:- 1. Meaning of Centering 2. Methods for Locating Centres 3. Turning Work Supported between Centres 4. Rough Turning between Centres. Meaning of Centering: Work to be turned in the lathe may be either held in the centres; or fastened in a chuck, or clamped to the faceplate. The work which is to be [...]
In this article we will discuss about:- 1. Meaning of Lathe 2. Working Principle of Lathe 3. Size of a Lathe 4. Specification of a Lathe 5. Classification of Lathe 6. Accessories Supplied with Lathe 7. Preparing Lathe for Operation 8. Safety Guidelines for Working on Lathe 9. Precautions on Lathe Operation 10. Check-Out Procedures for Operation on Lathe 12. [...]
Description of various parts of lathe has been given below: Part # 1. Bed: It is supported on broad box-section columns and is made of cast iron. Its upper surface is either scraped or ground and the guiding and sliding surfaces are provided. The bed consists of two heavy metal slides running lengthwise, with ways or V's formed upon them. [...]
Work holding and supporting is an important aspect of an engineer. All the work has to be held properly for machining. A good method helps in achieving economy and efficient manufacturing. Standard work holding devices used in lathe operation are: 1. Chuck 2. Lathe Centres 3. Collets 4. Carriers and Catch Plates 5. Face-Plate 6. Mandrel 7. Steady Rest 8. [...]
Setting is the preparation of the lathe for a specific operation according to the manufacturing process in order to ensure the required production rate, accuracy, and surface finish. After setting, two or three work parts are processed and checked, and if their size deviates from the values stated by the drawing, the tool position is corrected to obtain the required [...]
Work that cannot be readily mounted between the lathe centres is usually held in a chuck. Many machining operations can be performed on work held in a chuck, such as threading, boring, turning etc. Independent (4-jaw) chuck of lathe is used more than other types because it can hold practically any shape of work and can be adjusted to any [...]