The devices which hold and support the work or tool on a lathe are called lathe accessories. Common lathe accessories are a chuck, face plate, lathe center, steady rest, and mandrel.
Lathe Chuck
A lathe chuck is a holding device that is used for holding the job firmly against the cutting tool.
Types:Â
The following lathe chucks are generally used:
1. Four Jaw Chuck:Â
It is also known as an independent- jaw chuck which has four jaws and each jaw is moved separately with a chuck key. These jaws are reversible and have steps so that different sizes of works can be mounted. The chuck is used for holding regular and irregularly shaped jobs, heavier components, and large-diameter jobs. It consists of the following parts-back plate, body, jaws, and square threaded screw shaft.
Advantages:
- The job can be trued to within 0.02 mm accuracy.
- The workpiece can be set for eccentric turning.
- Large-diameter jobs can be held by using reversible jaws.
- Irregular workpieces can easily be held.
- It has more gripping power.
Disadvantages:
- The setting of the workpiece is more difficult as compared to that in the three-jaw chuck.
- It is not suitable for mass production.
2. Three Jaw Chuck:
It is also known as a jaw universal chuck, self-centering chuck, and concentric chuck having three jaws that work at the same time. Separate internal and external jaws are available with this type of chuck. Only a perfect round job and
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