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VICES USED IN MECHANICAL BENCH WORK AND TYPES OF VICES

 The vice is the most common tool for holding work. Various types of  vices are used for various purposes. They include bench vice, leg vice , pipe vice, hand vice, pin vice and  tool maker's vice. 

Bench Vice : The most commonly used is the engineer's parallel-jaw bench vice, sometimes called fitter's vice. It must be firmly fixed to the bench with coach screws , or with nuts and bolts. The vice essentially consists of cast iron body, a fixed jaw, a moveable jaw - both made of cast steel , a handle, a square-threaded screw, and a nut- all made of mild steel. Separate cast steel plates known as jaw plates are fixed to the jaws by means of set screws and they can be replaced when worn. The holding faces of the jaw plates have teeth for holding the work firmly but this has some disadvantage for soft metal which may be damaged when firmly held between the faces. Protective grips or "clamps" which can be made of lead , fiber, tin-plate , etc. are, therefore,  usually fitted over the jaws to prevent the serrations damaging the surface of the finished work. The movement of the vice is caused by the movement of the screw through the nut fixed under the movable jaw and the screw is provided with a collar inside to prevent it from coming out of the jaw when revolved. 

The size of a vice is known by the width of its jaws. The width suitable for common work varies from 80 to 140 mm , the maximum openings being 95 to 180 mm.


Bench Vice


Leg Vice : The Leg vice is used by blacksmiths but it is also suitable for heavy hammering, chipping, and cutting in fitter's work. The vice is secured to the top of bench by a strap which is fastened to a plate bolted to the bench top. The leg of the vice is fastened to the bench leg with staples and its ends fit into a hole in the floor. This construction of the vice makes it suitable for heavy work. One disadvantage of this type is that the jaws come together like arms of a letter "V", therefore don't provide such a firm grip as the parallel jaw type. 


Leg Vice


Pipe Vice : The Pipe Vice is holding round section metal, tubes, pipes, etc. In this case, the screw is vertical and the moveable jaw works vertically. It grips the work at four points on its surfaces. 


Pipe Vice


Hand Vice : The Hand Vice is used for gripping screws, revets, keys, small drills, and other similar objects which are too small to be conveniently held in the bench vice. This is made in various shapes and sizes. The length varies from 125 to 150 mm and the jaw width from 40 to 44 mm.

It consists of two legs made of mild steel which hold the jaws at the top and are hinged together at the bottom. A flat spring held between the legs tends to keep the jaws open. The Jaws can be opened and closed by a wing nut which moves through a screw that is fastened to one leg and passes through the other. 


Hand Vice


Pin Vice : The Pin Vice is used for holding round material of small diameter such as wire and pins, during working. It also forms a very useful handle for small files. It consists of a handle and a tapered nose covering a small collet chuck at its end. The chuck carries the jaws which are operated by turning the handle. 


Pin Vice


Toolmaker's Vice : The Toolmaker's vice is particularly useful for holding small work which requires filing or drilling., and for such work as laying out small jobs on the surface plate. It is made of mild steel. 

 

Toolmaker's Vice

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