Figure 29. Special Purpose Pliers.

thicknesses of friction tape, rubber tape, or specially manufactured rubber grips.

When cutting large material within the capacity of diagonal cutting pliers, cut

with the throat of the jaws, not with the points. The tendency of misalining the

jaws will be greatly reduced. Once the jaws are misalined (sprung), it will be

impossible to cut fine wire. To preserve the life of slip joint combination

pliers, do not use them on very hard metal. Hard metal will wear off the teeth and

the pliers will lose their grip. Use pliers only for the purpose for which they

are intended. Do not try to increase the leverage of their handles by lengthening

them with sections of pipe or other extensions.

f. Vises.

Vises are used for holding work when it is being planed, sawed,

drilled, shaped, sharpened, riveted, or when wood is being glued.

(1) Types of vises.

(a) Machinist's bench vise. A machinist's bench vise (fig 30) is a large

steel vise with rough jaws that prevent the work from slipping. Most of these

vises have a swivel base with jaws that can be rotated, while others cannot be

rotated. A similar light-duty model is equipped with a cutoff. These vises are

usually bolt-mounted onto a bench.

(b) Bench and pipe vise. The bench and pipe vise (fig 30) has integral

pipe jaws for holding pipe from 3/4 inch to 3 inches in diameter. The maximum

working main jaw opening is usually 5 inches, having a jaw width of 4 to 5 inches.

The base can be swiveled to any position and locked. These vises are equipped with

an anvil and are also bolted onto a workbench.

(c) Clamp base bench vises. The clamp base bench vise (fig 30) usually

has a smaller holding capacity than the machinist's or bench and pipe vises and is

clamped to the edge of a bench. Holding capacity is generally 1-1/2 to 3 inches.

These vises normally do not have pipe holding jaws.

22