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one screw its borer will be in the proper place for one hole; and when inclined to the other screw, it will be in the proper place for the other hole; and this distance between the holes can of course be increased or diminished as reqviired to suit thick or thin blocks. The borers can be unscrewed near the ends of their spindles at b, to put on one of a larger or smaller size. The points of the screw-centres at L, on which the frame of the borer E vibrates, can be put into different holes in the frame, so as to alter the difference of level between the two borers, to suit blocks of different sizes; and the screw *. is changed for one with a thicker head, or a washer is put upon its head. The stop x can be altered in position, by sliding it further from or nearer to the frame.
6. The block thus prepared by the boring machine is taken to the mortising machine, Fig. 151. This machine is moved by an endless band passing round a drum at A, screwed to a fly-wheel B. This drum turns an axis D, at the extreme end of which is a crank, with a long rod extending from it up to a joint at a, by which it is connected with a frame E, fitted between sliders b d, and guided by a cylindrical rod v, sliding through a fixed collar. In this way the frame is moved up and down when the axis D revolves. To this frame the chisels are attached, and operate upon the block fixed at o in a carriage H, sliding horizontally in the frame of the machine. At e are three screws of the same size as the screw B of the boring-machine, each furnished with a similar ring at the end. This ring enters the impression made by the boring-machine, so as to fix the block in its proper position when the screw is turned. This forces the other end of the block against the cross-bar of the carriage, which has three steel circles fixed to it opposite the end of the screw e. Each of these rings inclndes two smaller rings with a sharp edge, and the pressure of the screw e forces the block against these rings, and prints their figure in the wood. By this contrivance the block is held quite fast in the carriage while being mortised. Behind the carriage is a large double-wormed screw K, and this is received through a nut turning round in a fixed collar, supported by a bar across the frame. To this nut two wheels g h are fixed: the former is a large ratehetwheel; the latter a cog-wheel with a smaller one gearing with it, and fixed to the end of a long axis k furnished with a winch r. When this is turned round by hand, the nut of the screw is also turned, and the carriage is moved slowly backwards or forwards. In this way the carriage is adjusted to the proper point for beginning the work. The gradual advance of the block to each cut of the chisel is produced by turning the ratehet-wheel g by the following contrivance. The axis D has an eccentric circle I fixed upon it, which as it revolves acts upon a roller K fixed in one arm of a bent lever; the other end of this arm has a rod m jointed to it, with a tooth in the middle, which engages the teeth of the ratehet-wheel, and turns it round, a tooth at a time, as the rod moves backwards and forwards. The extreme end of this rod rests
upon a lever » (except when being drawn over the sloping side of the tooth of the ratehet-wheel), the centre of which is a pin fixed in the vertical column of the frame. It is held up by a second lever, o, supported on a cock screwed ou the frame. The opposite end of this lever is made so heavy that its weight is sufficient to raise up n and m, so that the tooth of the latter will be too high to intercept the teeth of the ratehet-wheel in its motion. The heavy end of the lever is kept up by a piece of metal fastened to the side of the carriage, at p, by screws passing through oblong grooves, so that it can be attached at any part along the length of the carriage. By this means, when the carriage has advanced as far as required, the loaded end of the lever o falls off the piece p, and disengages the rod m from the ratehetwheel. The fly-wheel and drum which turn the machine are fitted on a cylindrical part of the axis, so as to move freely thereon when it is not required to work the machine. A conical wheel s, with a hollow axis or tube centre-piece, is fitted upon the axis D so as to slide freely endwise, but is confined to revolve at the same time by fillets inserted in it. The end of the tube of the wheel s is formed into a circular groove, which is embraced by a forked lever L, centred in the opposite side of the frame. By moving the end of L towards the fly-wheel, the conical wheel s is thrust forward, and jammed into the inside of the drum A. This exactly fits the wheel, and the friction caused by the contact of the two conical surfaces is sufficient to work the machine. But when the lever L is pulled away from the flywheel, the conical wheel is drawn out from the rigger, and the fly-wheel detached from the axis, so as to revolve upon it freely without turning it.
In using this machine the block is applied with its screw mark to the end of one of the screws e. If a double block is to be mortised, as in Fig. 151, the centre screw is used; but if 2 single sheaves are to be fixed in, the 2 outer screws are used. By screwing it tight, the block is fixed between the double circle points before mentioned. To guide the block to its proper position, so that the hole bored for the commencement of the sheave hole shall be vertical, the block being fixed, the handle r is turned till the hole is brought beneath the sliding frame. The chisels are now adjusted. These are long square bars of steel Tt, fastened to the frame by a clamp. The back of each chisel has a small piece of steel attached for thrusting out the chips which it cuts, to prevent the hole from being clogged up. It has also two small cutters or scribers, fixed perpendicular to its edge, and projecting rather before it, so that in the descent of the chisel, two small clefts are cut or scribed, which inclnde the width of the chip to be cut out by the chisel in the succeeding stroke. By this means the mortice has its sides perfectly smooth. The back of the chisel is rounded to conform to the hole bored in the boring machine.
The clamp to which the chisels are attached passes behind the cross-bar of the frame, and the chisels being put exactly over the holes which are to become sheave-koles, are screwed fast by means of clamps. The machine is now put in motion by depressing the handle p, which is at the end of a lever, the fulerum of which is a pin fixed in the column of the frame at s, and a short arm gives action to the end of the lever L, so as to put the machine in motion. At the first descent of the chisels, they cut down through the whole depth of the holes previously bored, so as to give them a flat side when they rise up. The eccentric circle I, moving the bent lever and rod m, turns the ratehet wheel round on both and advances the block through a small space in the direction of the fly-wheel, so that the chisels in descending cut a fresh space, and in ascending the block advances. In this way the sheave-holes are rapidily cut, each chisel making from 110 to 150 strokes per minute, and cutting at every stroke a chip as thick as pasteboard with the utmost precision. When it is completed, the loaded end of the lever o drops off the piece p previously adjusted, and raises the rod m, so that the further advance of the block is prevented. The attendant then raises the handle P, which stops the machine. The finished block is now removed and a fresh one put in: the handle r is screwed back to bring the block to the proper point, and the machine is set in motion as before. By an adjustment of the cross bar in the back of the carriage, the mortising machine is adapted to blocks of different sizes, and the frame E may have any number of chisels fixed to it corresponding to the number of mortices required to be cut.
7. The corners of the block are next cut off by means of the corner saw, Fig. 153, which consists of a mandrel mounted in a frame A, carrying a circular saw L on its extremity. The frame of this mandrel
Fig. Ij2. The Corner Saw
is screwed down upon the frame Bb, which is supported by four columns, cc Dd is an inclined bench or trough, in which a block, as E, is laid, being supported on its edge by the plane c, and its end kept up to its position by the other part of the bench D. By sliding the block along this bench it if applied to the saw, which cuts off its four angles in succession, by applying its different sides to the trough. In the figure, two of the angles have been cut off and the third is just marked by the saw. By laying pieces of wood of different thickness against the plane D, So as to fill it up, the block is kept
nearer to or further from the saw, and in this way different sizes of blocks can be cut.
8. The blocks thus prepared have their outside surface formed to their true figure by means of the shaping machine, Fig. 153, the principal part of whieb is the chuck which holds the blocks. This consists of two equal wheels, A, B, mounted on the same axis, A being firmly fixed, while B slides upon it so as to render the space between them greater or less, as may be required for blocks of different lengths. This is effected by means of five bolts and nuts, the heads of the nuts being shown at x. Both wheels are divided into 10 equal parts. At each of these on A, a short axis or mandrel is fitted through a projecting part of the rim of the wheel. On the outside of the wheel each of these mandrels has a small wheel a fixed upon its end. On the ends in the inside of the wheel the mandrels have each a short cross-bar fixed, sufficiently long to contain two steel rings, which arc exactly the same size and distance apart as those in the morticing machine, which support the block. The wheel B has at each point opposite the mandrils a, a screw centre similar to the back cent 'e of a lathe, but furnished at its point with a steel ring of the same size as that at the end of the screw of the boring machine. The blocks are held in between the wheels by putting the double point at one end of each block, against the double rings at the end of one of the mandrels; and then, screwing the screw in the other wheel tight up, the block is confined between them. In this manner the chuck being filled with 10 blocks, if they are turned round rapidly and a chisel or gouge be fixed for them to cut against, each will be formed to a segment of the circle in which they move. This gouge is supported in a frame moving on a fixed rest D, which is curved to a circle whose centre is in the centre of the chuck. It is confined to move on this arch by a curved radial bar E, fitted to centre on the floor beneath the machine at one end, and having the other attached to the frame F which supports the tool. This frame contains a slider f moving in a groove, and at the end carrying the tool g in a holder. The slider has an axis or spindle fitted perpendicularly in it at h. On the lower end of this is a roller, which applies itself against a curved piece of metal i, called a shape, fixed upon the framing. The roller is kept in contact with the shape by a lever centered at k on the frame 7, and connected by a short coupling iron with the slider f; so that when its handle / is pressed towards the machine, the roller is kept up to the shape. By means of a handle o jointed to the frame P, which carries the tool and all its apparatus, this frame can be moved along the rest D, being guided by the radial bar E in its motion. Now if the other handle / be at the same time pushed fonvard, the roller applies itself to the shape, and the gouge describes the same curvature as the shape. Below the first shape is a second m, and by a simple movement the roller can be depressed so as to roll in the second shape, and give the curvature of it to the tool instead of the upper one.
Supposingthe 10 blocks to be fixed as just described, the frame F of the gouge is turned to one end of the rest D, and the chuck put in rapid motion, by a band round a pulley n, on its axis. The attendant, with the handle G in his right hand and / in his left, sweeps the frame along its rest by the handle G, while he keeps the roller in contact with the shape, by pressing the lever / towards the machine. In this movement, the gouge cuts to their proper curvature the faces of all the 10 blocks which are farthest from the centre. When the frame has slowly traversed the whole length of its sweep, the outside faces of all the blocks are finished, and the machine is stopped by casting its movement off from the mill. But as it preserves a considerable velocity, this is checked
by a steel spring at I, fixed at one end to the frame, and extending round a wheel fixed on the pulley H. The other end of this spring has a handle, which being pressed down, the curved part of the spring encloses the wheel and acts as a gripe. When the motion ceases, the blocks are all turned one quarter round on the small mandrels a, by an endless screw on each of the wheels a. These screws are cut in the ends of as many spindles d, pointing towards the centre of the chuck. At the ends of those nearest the centre, each spindle has a small bevelled wheel e fixed upon it. There is also a large bevelled wheel K fitted upon the axis, between the wheel A and the pulley u, so as to slip freely round upon the axis, I and when it is turned round, it will evidently turn all
the wheels, spindles, screws, and mandrels at once, and thus turn all the blocks so as to bring another face outwards. While the chucks are turned round, the wheel is held fast, and the wheel K is stopped by a catch L, moving in a joint fixed on the ground. This wheel being detained, the attendant takes hold of the chuck by its rim and turns it round 4 times, and the bevelled and other wheels are so proportioned that those 4 times will make the blocks revolve exactly one quarter on their separate axes, so as to bring another side of each block outside. The machine is then set in motion as before, and the work is alternately stopped and carried on until all four sides are finished, the upper shape being employed to
cut the third side in tne same manner as the first, and for the second and fourth sides, the lower shape is used. By means of a screw ■>, the socket supporting the axis of the roller h can be moved along the slider, the effect of which is to project the tool g more or less beyond the shape, as may be required to cut larger or smaller blocks. The same shapes will serve for several different sizes.
This machine is surrounded by an iron cage (a portion of which is shown in Fig. 153), for the purpose of defending the workmen, lest the blocks which are revolving with great velocity should be loosened by the action of the tool, and fly out by their centrifugal foree.
9. As the blocks come from the shaping engine, they are taken to the scoring engine, which forms the groove round their longest diameters for the reception of (heir ropes or straps. This engine receives two blocks A, B, Fig. 154, each held between two small pillars, a fixed in a strong plate D, and pressed against the pillars by a screw b, which acts on a clamp d. Over the blocks a pair of circular planes or cutters, E E, are fixed on one spindle, which is turned by a pulley in the middle. This spindle is fitted in a frame r E, moving in centres at e e, so as to rise and fall when moved by a handle f. This brings the cutters down upon the blocks, and the depth to which they can cut is regulated by a curved shape g, fixed by screws upon the plate D between the blocks. Upon this rests a curved piece of metal,
Firf. 154. THE sCOaiNO ENGINE.
h, fixed to the frame F, and enclosing, but not touching the pulley. To admit the cutters to traverse the whole length of the blocks, the plate d is sustained between the points of two centres, which are furnished with screws at /. On depressing the handle L, the frame is inclined. At m a lever, weighted at the end, counterbalances the weight of the blocks and plate D, all which are above the centre on which they move. The frame r has also a counterpoise to balance the cutters, &c. The cutters E are circular wheels of brass with round edges; each has two notehes in its circumference at opposite sides, and, in these notehes, chisels, fixed by screws, project beyond the rim of the wheel.
In using this machine, the block is pressed between the Wo pins, a, and the clamp d is screwed up against it. This clamp has two claws, each furnished with a
ring, which enters the double points before mentioned in the end of the block. The blocks being properly mounted, the attendant presses the cutters E E by means of the handle/down upon the blocks, depressing them between their pins until their descent is stopped by the piece h resting on the shape g. He then turns the screws b b, to fix the blocks tight, and the cintters being put in motion will cut the scores, which, by the adjustment previously made, will be of no depth at the pin-hole; but, by depressing the handle L so as to incline the blocks, and keeping the cutters down upon their shapey by the handle/ they will cut any depth towards the ends of the blocks which the shape g admits. In this way one quarter of the score is formed; the other is done by turning both blocks together half round, by the following contrivance:—The centres / are not fitted into the plate D, but into a frame at R beneath the plate, which is connected with it by a centre pin, exactly midway between the two blocks, A, B. A spring cateh, the end of which is seen at r, confines them together; when this cateh is pressed back, the plate D can be turned about upon its centre pin so as to change the blocks end for end, and bring the unscored quarters or those over the clamps beneath the cutters; the workman, taking the handles / and L one in each hand, and pressing them down, cuts out the second quarter. This might have been done by simply lifting up the handle L, in which case, however, the cutter would have struck against the grain of the wood, but by reversing the blocks, it always cuts clean and smooth in the direction of the grain. The third and fourth quarters of the score arc cut by turning the other sides of the blocks upwards and repeating the above operations. The shape g can be shifted for different sizes and curves of blocks.
As some of the snaping machines cut the wood without reference to the grain, roughnesses are left which require to be smoothed down. This is done by hand, and a smooth polished surface is produced without removing any of the wood.
10. For making the sheaves, the first process is cutting pieces or llakes off the end of the trees ot lignum vitse, of the proper thickness to form the sheaves. This is done by means of three converting machines, one with a reciprocating saw and the others with circular saws. The flakes are made circular, and their centres pierced by means of a crown sau> which has a centrebit in the axis. The flake being fixed before this saw, it quickly cuts out a circle,;nd, at the same time, forms a centre hole.
11. The coaking engine is a most ingenious machine; it forms a cavity in the centre of the sheave for (he reception of the coak or bush of bell-metal, which forms a socket for the centre pin. This cavity is in the form of three small semicircles, arranged at almost equal intervals round the hole formed by the last machine.
12. A drilling machine for perforating the three semicircular projections of the coaks, for the reception of short wire pins or rivets, which are rivctted down at the same time with the rest of the coak.