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Stereotyping Equipment

( Originally Published 1927 )

In completing this booklet, we come to the equipment necessary to handle the present day methods of stereotyping. The plaster pot disappeared when the Frenchman Genoux invented papier-mache mats for stereotyping, and the paste pot and steam table began their journey to ultimate oblivion when the dry mat cold process was invented. The brush beating of mats by hand was temporarily displaced by the brush beating machines invented and built by Partridge in Chicago in 1899 and by Derriez of Paris in 1900, and then this antiquated method gave way to the roller or mangle method of molding mats.

A brief outline of the development of stereotype equipment and a description of modern dry mat cold process machinery which a foundry must have, follows:

A DRY MAT HUMIDOR. This device was not known in the use of the plaster of Paris and wet papier-mache mats, these being moist or wet matrices. The advent of the dry mat necessitated the invention of the humidor or moistener. The first and basic patent taken out on a humidor was granted to J. FREMONT FREY of Indianapolis in 1913. His specification states that his device is to be used for conditioning (moistening) and thereby making dry mats softer and more plastic, in order that they take the type impression more readily and accurately and with greater depth.

Frey's humidor is a galvanized iron box, closed airtight.

On the inner surfaces of the vertical walls there are provided a number of vertical guide-ways opening at the top but partially closed at the bottom. These guide-ways or slots receive moisteners in plate form made of a special kind of clay, which absorbs water easily and allows it to evaporate readily. The humidifying of the mats which are placed in a rack or frame in the center of the humidor, is a uniform one. Frey uses no heating device, the moistening being effected by cold water.

The John Breuer humidor is constructed of either galvanized iron or copper. From a receptacle on top of the humidor water is fed to mineral slabs or blankets, which line the walls, by means of wicking enclosed in lead tubes. Later imitators advocate the use of gas or electric heat, so-called hot water moistening.

MOISTENING MACHINES. A very recent invention is the dry mat moistener. This is a precision machine which moistens the backs of the mats more evenly than is otherwise possible. The mats treated in this way need be seasoned for only two or three days.

STORAGE OR CONDITIONING BOXES. These boxes are made in different sizes, the best adapted ones are of galvanized sheet iron, measure 26 1/2 x 22 x 6 1/2 inches (inside measurements) and hold one hundred humidified dry mats. The mats remain in the boxes from 5-7 days in order to evenly distribute to each and every mat the moisture taken up in the humidor.

A DRY MAT ROLLER OR MANGLE. The older types of mat rolling machines were designed to facilitate the handling of wet mats, thus eliminating the extremely slow process of beating in with the brush. These older machines were operated at one speed only, were usually driven by a single upper rack, the mats being rolled twice, once forward and then back, and used only on wet mats. With the introduction of the cold dry mat process, however, difficulty was experienced with machines of the old design, as the speed at which they usually were operated was too great to give proper results when this method of molding was employed. Also, owing to the different texture of the dry mat from that of the wet mat, and the fact that the gears and upper rack were thrown slightly out of pitch when in operation—thus causing the machine to develop lost motion—there was a tendency to break off letters where parts of the face overhung the type body.

The newest type of roller is equipped with a variable speed motor, which is instantly adjustable for rolling in either wet or dry mats. Many of the existing wet mat rollers can be altered to accommodate dry mats. The general time of travel in one direction of the roller for wet mats was 5 seconds, for dry mats it is from 15-40 seconds. The makers of rollers are Duplex, Goss, Hoe, Scott and Wood. Another means of molding dry mats is the direct pressure molding press, which is now used in great numbers in Europe. (In 1920, for instance, Germany had 118 direct pressure molding presses and 197 rollers). These presses are now being introduced in the United States. The first hydraulic press was built in 1911 by Rockstroh and Schneider; many different systems followed their example. The presses built in this country are the Birotadruck and the Hoe, both introduced during 1926.

A DRY MAT SCORCHER OR ROASTER. A scorcher is a device used for thoroughly drying molded mats by evaporating the moisture out of them preparatory to casting the stereotype plates. Every kind of mats must be dried, thus plaster of Paris mats, clay mats and wet mats were first dried in kilns or ovens, then on hot plates, in flat driers, on steam-tables or on the Pape or revolving scorcher. The Pape wet mat drier was invented in 1885 by an Italian master stereotyper of the "Daily Telegraph" in London, and was the first of its kind. With this machine the matrix is dried by a rotary motion, hot air and steam working in unison.

The steam-table was most probably invented in 1856 by the Dellagana Brothers of London. The first reference to steam-tables in the United States dates back to 1861 at the New York Tribune. Here Craske and Collins were experimenting with papier-mache mats. The story has it that the steam-table was installed in the room directly above Horace Greeley's office and that due to a leak, hot water dripped through and scalded the famous editor's bald head. Mr. Greeley was so put out that steam-table operation had to be suspended for several months. Mayall and Hartnet of Boston in 1874 invented a combined steam-table and steam jacketed drying-oven, to cut down drying time from 13 minutes to less. Pearce and Hughes of England in 1880 invented a new method of drying a mat by removing the mat from the face of the form while it is in a moist condition and then confining same between a layer of heated plate and blankets with a perforated flat plate on top. In United States patent No. 128285 a method is described in which the matrix is removed from the form while still in a moist condition, and laid back downward upon an iron bed, its face being then covered with a layer of sand which filled all the intaglio parts of the matrix and served the same purpose as the type in preventing the face of the matrix from becoming distorted during the drying operation which followed. The use of sand in this manner is objectionable, because it is sure to adhere, to a greater or lesser extent, to the face of the matrix, so that its removal therefrom after the matrix is dry requires some time and labor, and the element of time is, as is well known, of the greatest importance in the operation of stereotyping. The present day dry mat scorchers are the Hoe, Goss, Scott and Wood semi-circular, the Duplex tubular (upright), the Wesel rotating, the Breuer flat, 1895, the Winkler centrifugal, and others.

From the roaster the mat is taken to the Casting Machine. There is no difference in these machines as far as casting from wet or dry mats is concerned. The machines consist of two parts, the melting pot and the casting boxes proper. The old-time melting pots, from which the metal was scooped with a ladle, was supplanted in larger establishments by the metal pumps, which were built into the metal pots, some holding up to 10,000 pounds of metal, or made in one piece with these pots. The heating was done with coal, later on with coal, gas, press-gas and electricity.

The slowly working hand casting boxes are still in use in small foundries, but have made way for AUTOMATIC PLATE CASTING MACHINES in larger newspaper plants. Of these latter there are two systems, the vertical and the horizontal machines. The vertical ones still retain the so-called tailpiece, whereas the horizontal ones have no tailpiece. The automatic casting machines are either semi-automatic or entirely automatic. With the former the casting is done by hand, the subsequent treatment, however, is done automatically by means of different mechanical steps. The first machine of this kind was the "Citoplate" invented and manufactured by C. E. Hopkins and Ferdinand Wesel, both of Brooklyn, N. Y. Then came the "COMPLEO" caster, made by Koenig and Bauer in Wuerzburg: then followed the Hoe, Duplex, Scott, Goss and the Autoplate junior casting machines. Another semi-automatic casting machine, now obsolete on account of the sensitiveness of its mechanism, was the "ROTOPLATE" invented by Egli.

Entirely automatic casting machines are: The STANDARD AUTOPLATE, invented by Henry A. Wise Wood of New York in 1900 and first used at the "New York Herald". With this machine the operation of casting is performed automatically from the time the mat is put in position until the finished plate is ready to be clamped to the printing press. In lieu of the six men hitherto employed, three men produce four plates per minute. The casting is done against a horizontal cylinder or core, the interior of which is cooled by water. Below it is a frame or "bask" carrying the mat. This back has an up and down movement of about six inches, and when it is in its top-most position there is a semi-circular space between it and the core equal in length, breadth and thickness to the plate which is to be cast. Molten metal having been injected into this space by a pump, there is a pause of a few seconds to permit of solidification, and then the back falls, bringing away the mat for another cast. Immediately afterwards the cylinder makes a half turn and presents what was previously its upper half to the mat for another cast. The first cast is taken with it as it turns, and is then pushed along from the top of the core against two rotating saws which trim its edges. Next it comes under a shaving arch, where it rests while its interior surface is smoothed to proper thickness and finally water is directed against its back to cool it without wetting its printing face. The Autoplate Junior is a semi-automatic plate casting-machine. The casting is done against a vertical cylinder or core, whereas in the Standard Autoplate the casting is done against a horizontal core. The Junior Autoplate has been found more practical and has supplanted the Standard machine.

Another completely automatic plate casting machine is the "MULTIPLATE" invented by Annard and built in England. This caster has a pump which is similarly constructed as in the Autoplate Standard. The machine is also a horizontal one, but the core is so made that it contracts under pressure. It takes the plate out of the casting receptacle or bowl into the boring, which then takes the plate to the part of the shaving bowl by means of an endless belt and deposits it upon a table.

A new development in the automatic casting machine field is the "WINKLER" Patent automatic plate casting machine. It is built in Switzerland and in Germany. A factory in the United States is now reported to be building the machine for the American trade. This machine embodies a number of patented features and new principles, which permit the production of perfectly true and solid stereotype plates : without "tailpiece"; without pumps ; without subsequent shaving; without trimming or handfinishing. In other words : after a short automatic operation, a perfectly finished stereotype plate is produced, which is absolutely ready for the rotary press. The fundamental idea in designing the "Winkler" casting machine was to directly connect the casting box with the melting pot, in such a way that the stereotype plate is cast without a tail but under the head of the whole contents of the metal pot, by gravity, that is to say, at a pressure most suitable for obtaining a perfectly true and solid plate. The machine consists of: (1) a melting furnace, (2) a hood with self-closing door, (3) one valve with automatic lubrication, (4) one pyrometer, (5) one enclosed driving gear with motor and starter, and one casting box comprising: one casting shell, one core, one matrix clamping device, two rings and an automatic water-cooling arrangement for shell and core. The operation : only work done by hand is: setting the matrix (once only) ; starting the machine by foot pedal; removing the finished plate; everything else being done automatically by the machine. Other claims for the machine are economy of metal, economy of fuel (50% saving), low casting temperature, higher output, less floor space required, and the use of exceptionally hard metal.

Other auxiliary machines used in stereotype foundries are : the combination saw and trimmer or similar individual machines used for sawing and trimming the plates. Routers for removing any protruding pieces of metal on the stereotype plate that might take ink and print. Shavers which smooth the interior surface of the plates. Bevelers, which form the bevels by which the plates are clamped to the presses. It goes without saying that all of these auxiliary machines as now used in stereotype foundries have in the course of time been simplified and improved.

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