The bars are usually cut to length by a guillotine, but it was considered that this tended to twist the metal, and perhaps unduly fatigue it; and as a consequence the firm have fitted John's shearing and notching machine, as constructed by Messrs. Henry Pels and Co., of Berlin. This new machine is illustrated on Plate XLI., adjoining page 95. The tool is shown in the act of cutting through a channel section. The cutting tool is seen immediately in front of the operator, and is actuated by gearing accommodated within the standards of the machine. When the cutting tool is brought down on the angle or beam to be sheared, and the shaft at the rear started, the rotation of an eccentric actuated by the shaft causes the point of the tool to slide idly a short distance to-and-fro on the bar. The hand lever on the right hand side of the machine is depressed, forcing the tool downwards, and the continued rotation of the eccentric causes the tool to pierce through the bar with a downward and inward motion. Where there is a deep web with flanges, the beam is reversed on the anvil, to enable the other flange to be cut. The cutting of any bar in this machine is a matter of only a few seconds.

Plate XLII.

IN ONE OF THE PLATERS' SHEDS.

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Of the platers' shed, where the plates, angles, bulbs, bars, etc., are machined, two views are given on Plates XLII. and XLIII., facing pages 96 and 98 respectively. It may be said generally that the machines are designed to deal with plates up to 50 ft. in length, and with angles up to 60 ft. in length, and of corresponding sections. It follows that the straightening and bending rolls, edge-planers, and punching and shearing machines, are of great power. It is scarcely necessary to make detailed references to all of the tools for these and other purposes.

All the tools are electrically driven. The plate-flattening rolls, which have 15 and 20 horse-power reversible motors, take plates 8 ft. wide, and the rolls are from 21-1/2 in. to 19 in. in diameter. The bending rolls are driven by a 20 horse-power motor. The plate-edge planers, shown to the left in the view, Plate XLII., facing page 96, are operated by 16 horse-power motors, and the plate is held on the table by means of hydraulic rams as well as screw-jacks. For drilling and countersinking plates there are several modern tools, each actuated by an independent electric motor. One of these is a three-standard drill, to deal with plates of the largest size. The spindles have a rise and fall of 10 in., and are fitted with self-acting, as well as hand, feed, and with the usual rack arrangement for the traverse of the head. Several radial countersinking machines, with 11-ft. jibs and spindles 2-1/2 in. in diameter, are driven by 10 horse-power motors. There are many heavy punching and shearing machines, nearly all of them having 42-in. gaps, so that they can punch holes at any part of the widest plates. As a rule, they are arranged to punch 1-1/2-in. holes through 1-1/2-in. plates at the rate of thirty holes per minute. The shears are of corresponding power.

For dealing with angles and bars there are several interesting tools, in addition to shears and punches. Some of the shears cut 8-in. by 4-in. angles, and are driven by 10 horse-power motors. There are channel-angle shearing machines, taking work 16 in. by 6 in., and operated by hydraulic pressure. These machines are made with revolving gear to suit almost any angle of flange.