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The other tools for roughing iron are the graver, Fig. 84, the side tool Fig. 85, bolt head tool Fig. 86, and FIG. 91. cranked tool Fig 87; there are numbers of others, but these are amongst the best. The graver is of almost universal application. It is merely a square rod of steel, ground off to a diamond shape, and hardened at the end. The point and the two projecting sides form the cutting edges.

The side tool is made of a triangular rod of steel, ground off as seen in the figure. The point, and the side of the triangle proceeding from the point, form in this case the cutting edges. As its name implies, it is used for side work, such as for turning the sides of collars, the ends of cylindrical rods, &c.; and this it will do, either to the right or left hand.

The bolt head tool is only used for tolerably heavy work; it has four cutting edges, and will take off a very heavy cut. The cranked tool has two cutting edges. It is used principally for turning the sides of collars, or parts at an angle to the centre line of the work, which it does with greater truth than the other tools sometimes used for that

purpose.

The chisels, Figs. 88, 89, 90, are used for smoothing and sometimes finishing articles of wrought iron, cast iron, malleable iron and steel. They are all used in a handle as shown at Fig. 91, and are generally made with three shapes of cutting edge, flat as in Fig. 88,

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angular as in Fig. 89, and half round as at Fig. 90. This difference, however, is only in the grinding, their sections being alike. The under edge of all these tools is serrated, so as to give them a better hold on the rest, and prevent them from slipping off. The position for holding them on the rest will be seen by referring to Fig. 92.

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Fig. 93 is the tool used for polishing wrought iron and steel. Its bottom is laid on the rest, so that the cutting edge is just level with the centres (see Fig. 94): it is then moved carefully along the rest, and only a very slight cut, or scraping of metal is taken off by it. Meanwhile the surface of the work is kept well moistened with oil or water. This tool requires considerable care and caution to prevent its catching in,' but, when it is

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properly used, a very bright smooth surface is given to the work.

Cast iron is smooth-turned by the tools or scrapers shown at Figs. 95 to 103. These are of various shapes for various kinds of work, but they are all of the same side section as given at Fig. 104; and their cutting edges being all ground off at right angles, they may be used either side uppermost. They are placed flat upon the

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rest, with the cutting edge about level with the centres

(see Fig. 105). The tools for roughing wrought iron, cast iron, and steel are made with a cutting angle of between 60° and 80°; and for polishing cast iron and brass, with an angle of 90°.

The clamps, Fig. 106, and the glazing stick, Fig. 107, are used for polishing cast iron, wrought iron, malle

able iron and steel. The clamps are lined with lead, as shown in the figure.

With regard to the best tools for turning brass and gun-metal, there is a great diver

sity of opinion. Some maintain that the ordinary hook-tools are the best when they are blunt; others prefer tools of circular sections which they roll along the rest; others use tools of square

FIG. 105.

FIGS. 102. 103. 104.

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section, and cut with all four sides, when one is dull the others are used in turn. This tool is effective, and when dull is easily ground.

FIG. 106.

FIG. 107.

Without, however, being able to lay claim to a long lifetime of experience, I have, nevertheless, turned

some hundredweights of brass and gun-metal, and, having tried all the tools, have found the hook-tools very liable to catch in'; the round-section tool liable to slip off the rest, and to require a deal of forcing to make it take a good cut; the square-section tool to be good, but only applicable to straight-work; but the ordinary round-nosed chisel, Fig. 90, to be well adapted for roughing every sort of brass. It can be used either upon straight or curved work, it is not liable to catch in,' does not require violent forcing, will take a light or heavy cut, does not easily lose its edge, and when dull is easily ground. It should be ground with a cutting angle of about 80°, and placed upon the

FIG. 108.

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rest, as shown at Fig. 108. For finishing or smoothing brass and gunmetal, the saine scraping tools are used, and in the

same manner as for

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cast iron. With regard to these tools, some prefer them to be thick and clumsy, and use them upon the ordinary rest; others use very thin scrapers, and to prevent 'chatter' place a piece of hard leather between the rest and the tool, to act as an elastic cushion, and to deaden the vibration. The best-formed scrapers are those thin at the cutting edge, but increasing in thickness and strength gradually towards the handle; and these can be used upon the naked rest without chatter. The chasing or wood-turning rest is the best for use with these tools; it should not be too far from the work, and should be

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