Wonders of World Engineering

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The many processes involved in the production of millions of copies of a periodical - such as typesetting, printing, folding, binding and trimming - are carried out by machines which work at remarkable speeds and with extreme precision


THE PRESS ROOM at the Park Royal Printing Works

THE PRESS ROOM at the Park Royal Works covers an area of 31,200 square feet. The roof, 30 feet above the floor, is carried on immense lattice girders 156 feet long. Powerful mercury lamps illuminate the press room at night and the ducts of the great ventilating system can be seen running along under the roof girders.

A THOUSAND tons of paper, converted into more than three million magazines at a speed of 144,000 copies an hour - that is the output of the world’s largest printing presses at Waterlow’s Park Royal Works, in London.

Hundreds of reels, each containing five miles of paper and weighing nearly a ton, are fed into the great machines, and the magazines are delivered folded and stitched, untouched by hand.

Centuries of progress have made such an achievement possible, but the basic principles of printing have not changed since the days of Gutenberg and Caxton. Human hands must in the first instance set up the type, although many ingenious machines are now in use to facilitate the work. The huge presses must also be prepared by hand for their colossal task. Except for working principles, however, modern printing machinery has nothing in common with the presses of the Middle Ages. The presses and auxiliaries in a printing works are not only capable of tremendous speeds, but they are also marvels of accuracy.

A tour of the works at Park Royal is an education in itself, and the plant and its operation can best be understood by considering the functions of various departments in sequence - from manuscript to magazines. Some of the manuscript, or “copy”, especially advertising matter, is set by hand, but this is not the hand setting that has served the printer for hundreds of years past.

The hand-set type at Park Royal is composed on the Ludlow system, that is to say, lines of matrices are first set in their correct sequence by the compositor. A matrix is a small flat piece of brass on which is deeply engraved a character of the alphabet, a figure or a sign. From the matrices, lines of type or “slugs” are cast in a special machine. The matrices are gathered as required by the compositor from a cabinet, to which they are returned after use.

This system of composing not only ensures greatly increased speed in preparing the type, but it also provides a brand-new set of perfectly-cast type letters for every issue. When a line of matrices has been assembled by the compositor in his matrix holder or “stick”, it is taken to the Ludlow machine for the casting operation.

The Ludlow machine presents to the observer just a polished table top, above which at the back is hung a long “pig” of type metal suspended on an arm, almost recalling the sword of Damocles. The lower end of the “pig” hangs in an electrically-heated melting pot, into which it is fed automatically as casting proceeds. On the top of the table is a machined slot in which is placed the composing stick with its line of matrices. At the side of the slot is a lever that locks the matrices in position ready for casting. On the touch of a lever at the front of the table, molten metal from the electric melting pot is pumped through a long, narrow slot in the type mould. The temperature of the electric melting pot is controlled thermostatically, but the throat and mouth are controlled by a rheostat at the back of the table. The molten type metal, having come in contact with the faces of the matrices, solidifies immediately into a slug of type.

The mould is maintained at a constant temperature by a stream of water pumped through its walls. Immediately the slug has been cast it is automatically trimmed to ensure that its height is accurate. It is then ejected on to a delivery slide at the front of the machine. The matrix stick is released as soon as the slug has been cast and the individual matrices are returned to their special storage cabinet so that the process can be repeated for a fresh line of type. An interesting feature of the machine is a repeat mechanism that makes possible the automatic casting of any number of slugs from the same set of matrices in the composing stick. The pumps that supply the mould with molten metal and the water for cooling are operated by an electric motor placed between the right-hand standards of the machine. This motor also drives the mechanism that delivers the slugs to the slide as they are cast.

The lines of cast type are arranged in galleys, long shallow boxes, ready for their final assembly in the framework or forme that represents another stage on the way to the presses.

Working in conjunction with the Ludlows are the remarkable Elrod machines, also electrically operated, which produce the “leads” and slugs for spacing purposes, and the “rules” that produce lines and borders of all kinds in the printed page. The Elrod machines present more marvels of ingenuity, and as their action takes place on an open table top they are fascinating devices to watch.

At one end of the table is an electrically heated crucible, containing molten type metal that is forced by a plunger into a mould of the required section. Two sections can be cast at the same time. On entering the water-cooled mould the strip or strips are solidified and then taken in charge by an automatic pulling mechanism. The pulling device draws the strip metal along to meet an adjustable gauge. When it touches this gauge, knives are brought into operation and the strip is cut automatically to a predetermined length. The Elrod machine is driven by an electric motor and is capable of producing strips of any length from 1-in to 20-in or more and of any thickness required by modern printing. The Elrod serves as an auxiliary machine not only to the Ludlows but also to the other type-setting machinery, the battery of Intertypes.

Typewriter Keyboard

THE THREE TIERS of one of the enormous printing presses at the Park Royal WorksIn general appearance and method of operation the Intertype machine resembles the linotype of the newspapers. On the Intertype machine at the left-hand side are the electric melting crucible, the driving mechanism, with its electric motor, and in front of this the table on to which the cast slugs of type are delivered. At the centre and on the right of the machine are the keyboards and above them the magazines, or stores, and the distributing gear that returns the matrices to the magazines after the casting operation. The action of the Intertype keyboard is similar to that of a typewriter, but instead of typing on paper, matrices are released from the magazine to the casting mould. Lines of type are cast automatically so long as the operator manipulates his keys.

THE THREE TIERS of one of the enormous presses at the Park Royal Works. The lowest tier, which is on the same level as the paper store, carries all the mechanism for mounting and running the reels of paper. The second tier contains the printing units and the cylinders which carry the stereo plates which impart an impression to the paper. The third tier assembles the sheets in correct order after they have been cut into strips.

The Intertypes at Park Royal are of two kinds. Some are fitted with single distributors, and these are used on work that requires only two kinds of type in the same line. The other Intertypes in the battery have double distributors, and these machines enable their operators to draw matrices from two, three or four magazines almost simultaneously. The ability to change from one style or size of type by the mere touch of a finger allows enormous speed in composition.

An amazing feature of these double distributor Intertypes is the mechanism that returns the matrices to their respective magazines. The individual characters are sorted out into their various styles and sizes before return to their magazine in correct alphabetical sequence. The Intertype machine can also be used for what is called “display work” - headings and advertisements. The display work on Intertypes and Ludlows reflects the ability and craftsmanship of the compositor despite the mechanical perfection of the machine. It is the man behind the machine who counts on this job, whether the work in hand be an excellently set advertisement from a Ludlow, or a setting at tremendous speed from the racing matrices of an Intertype.

The type from the composing machines and the blocks used, for printing illustrations are assembled in “formes”, one for two pages, and the formes are “locked up” by wedges or “quoins” within a steel chase, or frame. This process illustrates the skill and accuracy that printing demands. Everything within the chase must be type-high, a close-limit standard of height that measures exactly ·918-in. Again, type matter and blocks must be correctly alined and set square to the edges of the chase, and there must be no loose material of any sort, whether type characters, spacing strips, rules or blocks. The chase and its contents must be as one solid mass.

The chase has need of its solid strength for the next operation. This is the taking of an impression of the type and blocks within the chase, by a “flong” of compressed papier mache with a specially prepared surface. This process is carried out by hydraulic presses. The two Crabtree hydraulic presses at Park Royal are each capable of exerting a total pressure of 850 tons, or 6,000 lb on every square inch of the press head. The working of the press is simple and certain. The forme is placed on a table alongside the press head. On the chase is laid first the flong, then a layer of felt blankets to form a resilient surface for the flong. The felt blankets ensure that every detail of type and block shall be accurately reproduced in the flong.

The whole “sandwich” is then pushed into the jaws of the press and a gauge is set to the required pressure. On the turn of a switch an electrically driven pump is set in operation and the press begins its tremendous squeeze. At the predetermined pressure the electric pump stops automatically and after an interval the pressure is automatically reduced to a second predetermined level. The press is finally released by the operation of a hand lever. The flong, with its perfect impression of the type matter in the chase, is then ready for removal to the next department, the foundry.

Stereo Plates

AN INTERTYPE MACHINE having three main and three side magazinesAnother important feature of the composing room and of the whole works is the lighting system. When artificial lighting is necessary the composing room is flooded with the somewhat eerie radiance of powerful mercury discharge electric lamps that simulate daylight. These remarkable lamps afford excellent definition on black and white work, but the red rays of the spectrum are absent, and anything of a red colour in the composing room, foundry, or in the vicinity of the great presses, appears to be purple.

AN INTERTYPE MACHINE having three main and three side magazines. The term magazine used in this sense is a technical expression meaning store, and must not be confused with the printed magazine or periodical. The magazines hold the matrices from which type is cast on selection by pressing the required key on the keyboard. At the top of the machine is the distributing gear which returns the matrices, after they have been cast, to their correct positions in the magazines. The Intertype automatically casts type in lines of predetermined length and the lines of type (slugs) are delivered to the table on the left.

Great care has been expended, too, on the heating of the works. Three coke-fired boilers supply steam to various steam-heated batteries disposed throughout the factory. The heating arrangements work in conjunction with the ventilation system so that throughout the factory the air is properly conditioned. In the foundry, however, a separate ventilation system is provided to deal with the hot gases from the various machines.

TWO PAIRS OF TYPE CYLINDERS form one of the five printing units in each press at Park Royal WorksThe first foundry machine to which the composing room flongs are taken dries them in a semi-cylindrical shape ready for the stereo machines. These comprise first the machines that cast stereotype semi-cylindrical plates from the curved flongs. After they have been cast, the plates are trimmed ready for the cylinders of the great presses. The great press room covers an area of 31,200 square feet, and it is entirely free from obstruction. Thirty feet above the floor the roof, with its long windows facing north, is carried on immense lattice girders 156 feet long. At night the giant presses run under the light of the powerful mercury lamps, and high up among the roof girders are the flumes of the ventilating system.

TWO PAIRS OF TYPE CYLINDERS form one of the five printing units in each press at Park Royal Works. Each cylinder carries twelve semi-cylindrical stereo plates of two pages in duplicate, so that with each revolution of the press two complete copies of the periodical are printed. The press is 64 feet long and more than 20 feet high, covering a floor space of 2,964 square feet.

At one end of the press room is the enormous switchboard, with its intricate array of switches, meters, indicator lamps and circuit breakers. Electric power is supplied to the works at a pressure of 6,600 volts and a transformer station in the factory supplies current at 400 volts and 230 volts for power and lighting. For controls and feeds alone over fifty miles of electric cable radiate from the great switchboard, which is accommodated in a lofty gallery. Below the gallery is an immense open floor space, used as an auxiliary store for hundreds of reels of paper.

From below the switchboard the mighty presses present a magnificent spectacle as the first pair rise deck upon deck towards the roof. And behind the twin giants stand two more and behind those yet another pair - six Crabtree printing presses, the largest magazine machines in the world. Every press is 64 feet long and over 20 feet high. It weighs 225 tons and occupies 2,964 square feet of floor space. Each of these monsters will produce a 124-pages magazine, including a cover printed in two colours, ready folded and stitched at the rate of 24,000 copies an hour.

The great framework of each press is massively built of the highest grade cast iron, the best material in the world for the substructure of printing machines. The steel cylinders are machined from forgings and are finally ground dead true.

Each of the six presses comprises two machines in one, and each press has two electric driving sets that can be run independently or together as required. There are thus twelve driving sets for the six presses. Each driving set comprises a large three-phase alternating current motor for running at printing speeds and a small induction motor for the slow motion required when starting or during the “make-ready” operation. Special apparatus ensures that the change-over from the small to the large motors shall be smooth, to minimize any danger of breaking the paper web by “snatching”.

15,680 lb. of Ink

Should the web of paper break for any reason while the press is running, an electric detector mechanism is brought into operation. This automatically cuts off the power to the main driving motor and a gripper closes on the web where it enters the press. A brake is applied to the paper reel and the press is brought rapidly to rest. Powerful brakes are fitted also for stopping the press when required in the normal course of operation.

The great array of electrical power is controlled by push buttons arranged on control panels placed close to the presses. These panels are arranged man-high on pedestals and, with their indicator lamps and instrument dials, form part of the Meech system, on which the presses are driven and controlled.

Apart from paper there is one other primary ingredient. This is ink. At Park Royal 15,680 lb of ink are used for one average magazine issue and the ink is made on the spot.

CONTROL PANELS in the press room at Park Royal worksThe ink plant is in a separate department arranged on four levels for convenience in manufacture. On the top floor is a store for dry gas carbon black (a product of the gasworks), and a compound known as blue toner, whose function is to counteract the natural brown tone of the dry black. The more viscous ink media also are stored here. Below the black room is a stage carrying the electrically driven ink mixer and the machinery for making the blue toner. At the next level, the ground floor of the factory, are the ink grinding mills. In the basement are the tanks for the finished ink and the more fluid of the raw materials, with their attendant electric pumps. The ink supply is laid on in pipes which carry it from the manufacturing plant to the presses. A constant pressure head is ensured by powerful electric pumps.

CONTROL PANELS in the press room at Park Royal works contain all the switches required to operate the giant presses. A break in the paper is immediately indicated on the control panels and the presses can be started or stopped by pressing a button.

Adjoining the press room, at the switchboard end, is a paper store, with an unloading dock, at tailboard height, for lorries. A reel of paper is rolled off the lorry on to a low truck which is seized by four men and hurried off to one of the presses. The reel is halted below the press and one end is placed over a centre on which it can freely revolve. At the other end of the reel is inserted a short bar provided with five expanding jaws or “dogs”. On the turning of a wheel the dogs grip the interior of the reel of paper and hold it firmly.

The end of the paper is next fastened to guide tapes that lead it up through the press to a point where the web is slit into “ribbons”. At this point the tapes, after having fulfilled their purpose, are drawn out of action by the touch of a lever. Two reels are accommodated at the entering end of the press so that when one is used up the other can be brought into action without stopping the press.

Above the lower or paper floor, which is paved with steel tiles, is the second tier of the press which comprises the printing portion of the machine. In each press there are five printing units with two pairs of type cylinders on each unit. Each cylinder carries twelve semi-cylindrical stereo plates of two pages. As the paper passes between the revolving cylinders it is printed on both sides.

The top tier of the press assembles the ribbons, each a page wide, into which the web has been slit. This part of the press comprises a framework in the form of a tower containing the turning bars and rollers that guide the ribbons to the stitching, cutting and folding mechanism.

156 Miles of Steel Wire

When the ribbons have been brought together finally, layer upon layer, all travelling at tremendous speed, they enter the stitching mechanism.

The stitching is done by a pair of cylinders that revolve at high speed, cutting off their supplies of wire from reels. Thirty ribbons or webs of paper are pierced by the wire ends, which are clinched by dies in one of the cylinders. Each issue of a standard magazine passing through the six presses requires 156 miles of steel wire. After the stitching process, the ribbons are cut by revolving knives, and then follows the folding. A blade tucks each cut copy of the magazine into the jaws of a gap in a revolving cylinder. This carries the magazine round to meet a pair of rollers that nip the fold and lay the copy on a “gate” carried by a travelling belt. This belt moves slowly downward until it receives a quire of magazines. Then the belt moves forward rapidly and another “gate” comes into position for the next quire. The quires of magazines are delivered by elevator conveyers to the publishing room.

Here is an enormous “roundabout”, or slat conveyer, enclosing a space 105 feet long and 30 feet wide. Packers snatch the bundles of magazines from the roundabout, pack and label them, and then drop them into two central troughed belt conveyers. These conveyers deliver the bundles to two chutes that in turn supply the vans waiting at the factory doors.

Most of the vans at the output end of the works come from the great railway termini of London.

Three million magazines, the weekly output, require perfect organization if they are to be cleared speedily from the works. Such an issue requires over a hundred 10-tons railway trucks to transport it by rail. Spread side by side its pages would stretch for more than 20,000 miles.


IN THE FOUNDRY. Stereo machines cast semi-cylindrical plates from papier mache flongs. A flong is prepared by taking an impression from a forme of type previously set in the composing room. The hydraulic moulding presses used in making flongs exert a pressure of 6,000 lb to the square inch.

[From part 13, published 25 May 1937]

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