Vices

A vice is a tool used to hold objects securely to allow work to be performed on it.

The types of commonly used vices are discussed below.

Hand Vice: Its body is made from steel with the jaws hardened and tempered. The spring will keep the jaws apart with the wing nut, thus providing the clamping action. These vices are used for holding objects when drilling, riveting and similar works.

FIGURE

Bench Vice: It provides rigid support for work at the bench. It allows both hands to be used when sawing, filing bending and various other tasks. The two components of the bench vice are:

• The main body: Contains a fixed nut or a half not, which is bolted to the workbench.
• The sliding part: It fits into the main body and is moved back and forth by means of a screw thread. The jaws close by turning the screw thread in a clockwise direction with a help of a tommy bar whereas the jaws open when turned in an anticlockwise direction. With a quick release mechanism that is present in some vices, a half nut is used and operation of a live disengages it from the screw thread. A clam made from copper or aluminium is fitted in order to protect the objects with smooth surfaces and hardwood ‘V’ blocks are used to protect tubing.

FIGURE

Machine Vice: It is used to hold the work the machine pieces when drilling and shaping them. All machine vices give a parallel grip. The base of this vice is slotted so that it can be bolted down to hold the work steadily. This vice can be held by hand for light drilling works. The sliding jaw is moved by a screw thread, which is turned either by a knurled handle or a cranked handle. There is no quick release mechanism fitted to this type of vice.

FIGURE

Toolmakers Clamp: It is made of case-hardened mild steel and is used for holding small pieces of work together for riveting and assembling. A clip screwed to the top jaw locates screw A, thus preventing the jaws falling together when being adjusted. This type of clamp gives a parallel grip in all positions and are classified based on the length of the jaws. The jaws are adjusted to the approximate correct position and the final tightening is done by first adjusting screw A and then screw B.

FIGURE

The following are the precautions and maintenance instructions that has to be followed when using vices.

• Ensure the vice is clean.
• Keep the screw thread slightly lubricated.
• Mount the vice in such a way that the top of the vice is levelled with the worker’s elbow when in working position.
• Ensure the vice securing bolts are tight.
• Never use the vice as an anvil for hammering purposes.
• While using a machine vice for drilling on, care must be taken not to drill into the base of the vice. To prevent such damages, a piece of wood can be placed under the work to be drilled.
• Always clean the vice after every use.