Short Answer:

A chisel is a hand tool used in workshops for cutting, shaping, or removing material like metal, wood, or stone. It has a sharp-edged blade at one end and a handle on the other. In mechanical workshops, chisels are mainly used for cutting metal by striking them with a hammer. They help in removing unwanted parts from a surface or finishing the shape of an object.

There are different types of chisels based on the shape of their cutting edge and use. Common types include flat chisel, cross-cut chisel, round nose chisel, diamond point chisel, and cape chisel. Each type is designed for a special task such as grooving, cutting, or shaping metal with precision.

Detailed Explanation:

Chisel and its types

A chisel is a very useful and simple hand tool that plays an important role in mechanical, carpentry, and metalworking jobs. It consists of a hardened steel blade with a cutting edge and a handle that may be struck with a hammer. In mechanical workshops, cold chisels are mainly used for cutting and shaping metal, especially when machines cannot be used or for detailed manual work. The tool works by applying force on the chisel using a hammer, which causes the sharp edge to cut or remove a part of the material.

Structure of a Chisel

A typical chisel used in mechanical work has the following parts:

• Cutting Edge: The sharp part at the front that actually does the cutting.
• Shank: The middle part of the chisel which transfers the force from the head to the edge.
• Head: The end where the hammer hits. It is slightly wider to avoid damage.
• Bevel: The sloped surface near the cutting edge to give the blade its sharpness.

Chisels are made of hardened tool steel to withstand repeated hammer blows and to maintain sharpness.

Uses of Chisel

• Cutting metal sheets or rods manually.
• Removing burrs or sharp edges from a surface.
• Chipping away unwanted material from castings or forgings.
• Making grooves or keyways in metal.
• Shaping and finishing metal parts.

Chisels are often used when machine tools are not available or when precision handwork is required.

Types of Chisels

Different types of chisels are used for different jobs in mechanical workshops. The main types are:

1. Flat Chisel

• Shape: Straight and flat edge.
• Use: Most commonly used for general cutting and chipping of metal. It removes large flat surfaces.

2. Cross-cut Chisel

• Shape: Narrow cutting edge with sides tapered.
• Use: Used for cutting keyways, slots, and grooves in metal.

3. Round Nose Chisel

• Shape: Cutting edge is curved or semicircular.
• Use: Used for cutting oil grooves or channels in bearings or shafts.

4. Diamond Point Chisel

• Shape: Tip shaped like a diamond or V.
• Use: Suitable for cutting sharp corners and cleaning square holes.

5. Cape Chisel

• Shape: Narrow width at cutting edge, wider in body.
• Use: Used for cutting narrow grooves and slots with fine control.

6. Socket Chisel

• Shape: Has a socket instead of a handle.
• Use: Mostly used in woodworking, but in mechanical applications too for delicate shaping.

7. Paring Chisel (for precision work)

• Shape: Thin, long blade.
• Use: Used in fine fitting and shaping, mostly in light applications.

Safety Tips While Using a Chisel

• Always wear safety goggles to protect eyes from flying chips.
• Hold the chisel firmly and hit it with a hammer using controlled force.
• Do not use a chisel with a mushroomed or damaged head.
• Keep the chisel sharp for better performance.
• Use the right type of chisel for each job to avoid accidents or damage.

Conclusion

A chisel is a basic but very useful tool in any mechanical workshop. It helps cut, shape, and remove metal manually using a hammer. There are many types of chisels like flat, cross-cut, round nose, and diamond point, each designed for a special purpose. Knowing their types and uses helps in doing clean and accurate work without machines. Proper use and safety measures make chisels a valuable tool for both rough and precision tasks in metalworking.