Short Answer:

A bench vice is a very important tool used in fitting work to hold the workpiece firmly in one position while performing various operations like filing, sawing, drilling, tapping, or hammering. It is fixed on a workbench and allows the fitter to use both hands freely during the work.

The main function of a bench vice is to provide a strong and stable grip on the job so that it does not move or vibrate. This ensures safety, accuracy, and ease of operation while shaping or assembling metal parts in mechanical workshops.

Detailed Explanation:

Function of a bench vice in fitting

In mechanical workshops, especially during fitting work, many tasks are done manually such as filing, cutting, drilling, tapping, or chiseling. During these operations, it is very important that the workpiece remains fixed and does not move. For this purpose, a bench vice is used. It is a clamping device that holds the workpiece tightly on a solid surface, usually a workbench.

The bench vice is made of cast iron or steel and has two jaws: one fixed and one movable. The movable jaw is adjusted by rotating a screw handle. When the handle is turned, the movable jaw moves forward or backward to grip or release the job. Once the workpiece is fixed between the jaws, the fitter can use tools like files, saws, or drills easily and safely.

Main parts of a bench vice

1. Fixed Jaw – The stationary jaw which is permanently attached to the base.
2. Movable Jaw – The jaw that moves forward or backward to grip the workpiece.
3. Screw Mechanism – A threaded rod connected to the handle that moves the movable jaw.
4. Handle – Used to rotate the screw and tighten or loosen the jaws.
5. Jaw Plates – Replaceable plates with serrated teeth for better grip.
6. Base – The bottom part of the vice that is bolted to the workbench.

Functions of a bench vice in fitting

1. Holding the workpiece firmly
   The bench vice securely holds metal pieces so they do not move while working. This allows accurate operations like filing or sawing.
2. Improving safety during operations
   A loose workpiece can slip or rotate, which is dangerous. The vice ensures safe working by keeping the object in one place.
3. Allowing both hands free
   With the workpiece clamped in the vice, the fitter can use both hands to operate tools more effectively and with more control.
4. Reducing vibration and movement
   A bench vice helps absorb minor vibrations during operations like chiseling or drilling. This improves surface finish and tool life.
5. Enabling precise work
   For tasks like marking, tapping, or reaming, a steady workpiece is needed. The vice keeps everything aligned for accurate results.
6. Supporting multi-step fitting jobs
   Many fitting operations are performed step-by-step on the same piece. The vice keeps the part in a stable position throughout the process.

Applications of a bench vice

• Filing: Smoothing and sizing the edges of metal pieces
• Sawing: Cutting rods or sheets using a hacksaw
• Drilling: Making holes using a hand or bench drill
• Tapping and threading: Holding the part steady while making threads
• Marking and punching: Keeping the surface fixed during layout work
• Assembly: Holding parts during joining or aligning

Tips for proper use

• Always fix the vice tightly to the workbench
• Do not overtighten the jaws, especially on soft materials
• Keep the jaws clean and free of oil or metal chips
• Replace worn-out jaw plates to maintain good grip
• Use soft jaw covers when working with delicate or finished surfaces

Conclusion

The bench vice is one of the most useful and basic tools in any fitting workshop. Its main function is to hold the workpiece firmly so that fitting operations like filing, sawing, drilling, or tapping can be done safely and accurately. By keeping the job steady, it helps improve both the quality of the work and the safety of the worker. Every mechanical workshop depends on a bench vice for successful and efficient fitting work.