What is Capstan Lathe?
Capstan lathe is the modified form of the engine lathe and center lathe in which the tailstock is replaced with a hexagonal turret tool head. It was first developed by Pratt and Whitney in America in 1860.
It was necessary to develop a capstan lathe because there was only one tool holder in the center lathe and only one tool can be mounted in the tailstock. As a result, it was very time-consuming every time we had to change the tool while changing the operation to be performed on the workpiece. Center lathe was not suitable for mass production.
To overcome these problems, a capstan lathe was developed. capstan lathe is a modified form of the center lathe. This turret tool head has 6 different tool types. The turret tool is rotated to obtain the required tool for the operation.
It is used in mass production, i.e. to manufacture a large number of end products with the highest accuracy and precision in the shortest possible time.
It is a semi-automatic lathe. It is called semi-automatic because the machining processes such as drilling, facing, thread cutting, turning, etc. are carried out automatically without changing tools, while other works such as workpiece clamping, toolset, and cooling are carried out manually.
Working of Capstan Lathe
Six tools are available in the hexagonal tool holder in the capstan lathe. First, the workpiece, which is to be changed into the desired shape and size, is placed in the chuck.
This chuck can be a three-jaw or four-jaw chuck. This workpiece rotates with the chuck, which is connected to a spindle.
The hexagonal tool head has six different surfaces to accommodate six different tool types.
When the workpiece with the chuck starts to rotate, the hexagonal tool head is moved towards the workpiece by moving the saddle. This hexagonal tool head can be rotated and by turning the tool required for machining is directed towards the workpiece.
After the required tool faces the workpiece, the tool is brought into contact with the workpiece by advancing the ram and the required operation is carried out.
After the first operation has been completed and the ram has been moved backward, the turret automatically switches on and the tool mounted on the next face comes into operation.
What is Turret lathe?
A turret lathe is a type of metalworking lathe that’s characterized by the use of interchangeable cutting tools. Like traditional lathes, it presses a stationary cutting tool against a rotating workpiece.
Turret lathes are unique, however, because of their interchangeable cutting tools. The cutting tool can be quickly changed to accommodate a specific manufacturing application.
It evolved from earlier lathes with the addition of the turret, which is an indexable toolholder that allows multiple cutting operations to be performed, each with a different cutting tool, in easy, rapid succession, with no need for the operator to perform set-up tasks in between (such as installing or uninstalling tools) or to control the toolpath.
Benefits of Turret Lathes
Turret lathes are more versatile than traditional lathes because of their interchangeable cutting tools. Traditional lathes also often support multiple cutting tools, but these are more difficult to change than turret lathes.
To change the cutting tool in a traditional lathe, a worker must detach the existing cutting tool, remove it from the lathe, and then reattach another cutting edge.
Turret lathes, on the other hand, can be equipped with several cutting tools at the same time. The cutting tool does not need to be replaced. Rather, the turret lathe can automatically switch to the appropriate cutting tool, which leads to faster and more efficient production processes for manufacturing companies.
It takes only a few seconds for a turret lathe to be switched to a different cutting tool, while it takes a human worker several minutes to manually change the cutting tool in a traditional lathe.
Types of Turret Lathes
There are many different types of turret lathes. For example, some turret lathes are numerically controlled (NC) while others are computer-controlled (CNC). NC turret lathes are older and usually use punch cards or similar rudimentary control methods.
In comparison, CNC turret lathes are newer and use more advanced control methods that require the use of a computer. Turret lathes can also be classified according to how they work. There are automatic turret lathes that can perform a variety of processes with little or no manual labor.
There are also manual turret lathes that require at least some manual labor. Other common types of turret lathes are semi-automatic, vertical, and flat lathes.
Difference between capstan and turret lathe
Capstan and Turret lathes are the advancements of the Engine lathes and center lathes in which the tailstock is replaced by a hexagonal turret tool head with 6 different tools in the turret where the turret tool is rotated according to process requirements in each operation.
The capstan and turret lathe although appear to be identical at first sight but a lot of differences in construction, operation, and use. In this article, you can check it out some difference between these two lathe machines.
|Capstan lathe||Turret lathe|
|1. Lightweight machine.||1. Heavyweight machine.|
|2. These are usually horizontal lathes.||2. Turret tool head is directly fitted on the saddle and both of them appear like one unit.|
|3. Turret head is mounted on a slide called ram which is mounted on the saddle.||3. Suitable for heavier chucking work.|
|4. Suitable for bar work.||4. The saddle is moved to provide feed to the tool.|
|5. The saddle is locked at a particular point and the ram is moved to provide feed to the tool.||5. They are heavy and durable.|
|6. Only a limited amount of feed and depth of cut is provided for machining.||6. More feed and depth of cut are provided for machining.|
|7. The cross slide is mounted on a carriage that rests on the bed ways between the headstock and the ram.||7. Some turret-type lathes are equipped with side hung type carriage.|
|8. The turret tool head is indexed automatically.||8. To index the turret tool head, a clamping lever is released and the turret is rotated manually.|
|9. Feed stop screws are used to control the distance of tool movement which is at the rear side of the turret.||9. Limit dogs are used to control the distance of tool movement.|
|10. No such facility to moving turret at right angles.||10. Some turret lathes have the facility of moving the turret at right angles to the lathe axis.|
|11. Feed rod gives for longitudinal feed.||11. Feed rod does not give for longitudinal feed.|
|12. Used for mass production of small size equal part.||12. Used for mass production of large size equal part.|
|13. It has hand-operated collet chucks.||13. It is accommodated with power chucks.|
|14. Heavy cuts on the workpiece can’t be given because of non-rigid construction.||14. Heavy cuts on a workpiece can be given because of the rigid construction of a machine.|
What is the difference between Capstan Lathe and turret lathe?
In turret lathe, the main turret is directly installed on the saddle and the saddle is moved along the entire length of the lathe bed. Capstan lathe is a ram type of turret lathe and the movement of the ram is limited. In turret lathe, the turret tool head is directly mounted on the saddle and they appear like a single unit.
What is Capstan Lathe used for?
Capstan lathe is used for shorter workpieces because of limited ram movement. Turret lathe used for longer workpiece because of saddle movement along the bed. In Capstan lathe is used for machining workpieces up to 60 mm diameter.
What is Capstan Lathe machine?
A capstan lathe or a turret lathe is a production lathe used to manufacture any number of identical pieces in the minimum time. These lathes are the development of engine lathes. The capstan lathe was first developed in the United States of America by Pratt and Whitney sometime in 1860.
What are the main parts of capstan and turret lathe?
Following are the main parts of a capstan and turret lathe,
- Cross slide and saddle.
- The turret saddle and auxiliary slide.
Why is it called a turret lathe?
It evolved from earlier lathes with the addition of the turret, which is an indexable tool holder that allows multiple cutting operations to be performed, each with a different cutting tool, in easy, rapid succession, with no need for the operator to perform set-up tasks in between.
What is the difference between turret and engine lathe?
The tailstock of a turret lathe has a turret that can carry multiple tools, the tailstock of an engine lathe can hold only one tool of limited size. 8. Turret lathes need fewer skilled operators, and engine lathes need skilled workers to control.
What is turret lathe and its types?
A turret lathe is a type of metalworking lathe that’s characterized by the use of interchangeable cutting tools. Like traditional lathes, it presses a stationary cutting tool against a rotating workpiece. Turret lathes are unique, however, because of their interchangeable cutting tools.
What is the need of turret indexing mechanism?
The purpose of the invention is to effect an improved turret indexing mechanism adapted for automatic operation, in which all of the different working positions of the turret may be affected one after another if desired or some of them may be selectively passed over during the indexing, as predetermined by the adjustment of the mechanism.
What are the advantages of a turret lathe over an engine lathe?
Advantages Of Turret Lathe:
- Large number of tools can used without the need to replace the tool after each operation.
- Increase in production rate.
- Decrease in labor cost as less number of skilled labors are required.
- In this lathe, we can obtain different ranges of speeds.
What is a turret in machining?
A turret holds a group of tools and rotates to bring a new cutting tool into position. Changing tools involves: Pulling the current tool back, typically with a Z-axis or combined X- and Z-axis motion. Rotate the turret until the correct tool is in position.
What is a capstan operator?
Set and Operate Capstan Lathe safely and effectively. Adjust machine offsets when required. Monitor machinery and report problems. Monitor coolant levels and top up as required.
What type of chuck is used in capstan lathe?
The work holding devices used on the capstan lathe are generally automatic types. These automatic type work holding devices reduce the setup time. Collets are also called collet chucks. It is mainly used for long bar stocks of various shapes operated either by hand or by power.
What are the disadvantages of turret lathe?
A CNC turret can obtain accuracy and precision in the cutting process yet it is not possible to cut metals that are round in shape. The power consumption part for the CNC turret has a big drawback as it consumes more electricity. In addition, more space is required to set the machinery.
How is turret lathe classified?
As to size, turret lathes are classified as small (bar capacity d = 25 mm, chucking capacity D = 320 mm), medium (d = 80 mm, D = 500 mm) and large (d = 160 mm, D = 800 mm). According to the turret arrangement, turret lathes are classified as those having turrets with a horizontal.
Which turret lathe is used for heavy duty works?
The machine mentioned previously is lightweight but is not aptly suited for heavy chuck works; hence another version of the arrangement known as the saddle-type turret lathe is used for heavy-duty purposes. This allows for jobs having diameters even 5 times those that can be handled with the former type.
What is a capstan lathe used for?
A capstan lathe is a milling machine used to create the same parts over and over again. The cutting bits are mounted on a rotatable turret known as a capstan, which allows the user to quickly change the orientation of the bits for cutting without having to take off the first bit and then mount the second.
What is the need of capstan and turret lathes?
Capstan lathe is used for shorter workpieces because of limited ram movement. Turret lathe used for longer workpiece because of saddle movement along the bed. In Capstan lathe is used for machining workpieces up to 60 mm diameter. In Turret lathe is used for machining workpieces up to 120 mm in diameter.
What is difference between automatic lathe and capstan lathe?
Capstan and turret lathes are semiautomatic lathes. Semiautomatic means machining is done automatically but some other functions like changing of job/workpiece and set of tools are done manually.
What is Centre lathe machine?
The Centre Lathe is used to manufacture cylindrical shapes from a range of materials including; steels and plastics. Many of the components that go together to make an engine work have been manufactured using lathes.
What is the difference between Centre lathe and capstan lathe?
Capstan and Turret lathes are the advancements of the Engine lathes and center lathe, wherein the tailstock is replaced by a hexagonal turret tool head, having 6 different tools in the turret, where the turret tool is rotated in each operation according to process requirement.