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The Importance of the Pressroom

( Originally Published 1930 )

The pressroom is a necessary department in any complete printing plant. It receives the work that has been prepared in the composing-room, places it on the presses, and produces the printed articles. The final link in the chain of production is the bindery which assembles the printed sheets into catalogues, magazines, books, posters, circulars, and printed novelties of all kinds.

The appearance of a completed job depends to a great extent upon the work of the pressroom employees. The pressmen must see that the form is placed on the press in such a manner that it makes an even impression on all parts of the sheet, and that the margins are accurately located on the paper. The mixing of inks to obtain the proper color and consistency for the particular job is also a part of the work of the pressmen. Another of their duties is that of making sure that the ink is applied evenly to all parts of the rollers and the type. A job can be made very attractive and pleasing in appearance if all of the above and many more details are closely carried out by the pressmen. This means that the work of the pressmen and the other employees in the pressroom is of the highest importance in the industry. Therefore, it is advisable that we make a study of the pressroom and the workers in it so that we may have a knowledge of its place in the printing plant.

The Jobs in the Pressroom.óWe have seen that there are a variety of presses and different types of pressrooms. The jobs of the workers in the pressrooms differ with the types of machines which they are called upon to operate. Thus we find that there are men who specialize in platen-press operation, while others are cylinder pressmen. Then there are specialists in the handling of rotary presses of the sheet-fed or of the web-fed variety. In addition to the pressmen, every printing plant employs press feeders who assist in the work and whose particular job is that of feeding to the presses sheets of paper upon which the impressions are to be made. In the news-paper pressrooms where web presses are used the assist-ants are called flyboys. The above-mentioned workers are engaged in the printing processes which require raised surfaces to make the impressions. There are other groups of pressmen who print from flat or sunken surfaces. Their work will be discussed in other chapters.

Operations Performed. The operations performed in the pressroom are becoming highly specialized. As a result, the men in this trade are beginning to specialize in the handling of particular machines. In the following paragraphs we shall discuss the methods of operating the various presses and the duties of each worker in the shop.

Those forms which are to be printed on platen presses are received by the platen pressman when they come from the composing room. The press is inked before the form is put in place. He puts it on the bed of the press, which is vertical, and then he locks it in place. He covers the surface of the platen with packing which consists of a sheet or two of smooth-surfaced cardboard and several sheets of paper. Packing is placed on the platen in order to give a yielding surface for printing. The next thing he does is to place guide marks on the packing to enable him to put in the right position the sheet that is to be printed. The operations of marking out and overlaying then follow. In these operations, the purpose of which is to provide an even impression of the type on the paper, he pastes pieces of paper on the packing to cover those spots where the printing does not show up very well. Sometimes he builds up the form by placing pieces of paper under the type which does not print clearly. This is called underlaying. After the underlaying and the overlaying have been completed, a sheet of some tough stock (the draw sheet) is pulled or drawn over the pad-ding, guide pins to which the sheets are to be fed are inserted, and the grippers, the ink fountain, and other parts are adjusted. These operations are known as make-ready, the printers' short term for preparing the press and the job for printing. The pressman then prints a sheet or or two to make sure that everything is all right and he takes these to the foreman for his O. K. When everything is approved, he applies the power, and the printing process commences. One pressman with the assistance of feeders can handle several presses.

The platen-press feeder assists the pressman in the performance of his duties. He helps to get the press ready for operation, he washes the rollers, he oils the press, and he helps to keep it in good condition. One of his main duties, when it is a hand-fed press, is to feed the sheets to it. The feeding operation consists of placing the sheet on the platen, when the press is open, by sliding it to the position indicated by the guide pins. This is done with the right hand, and after the sheet has been printed, it is removed with the left hand as the press is opening. When the press is open, a new sheet is inserted. Some plants use mechanical feeders for the platen presses which eliminate the hand-feeding operation.

The cylinder pressman prepares the press for printing by inking and running it to allow the ink to distribute. Then he places the form on the bed, which is horizontal, loosens a trifle the quoins or wedges which surround the form to enable him to pound down the type in order to make it even in height throughout, tightens the quoins again, and then proceeds to lock the form in position. The packing of the cylinder is changed, and the guides are set. Then an impression is pulled or taken in order to determine the position of the printed matter on the sheet. This is done also to see what parts will need correction as far as the impression is concerned. The press-man proceeds to make ready by pasting overlays, which are pieces of paper, on the packing. These overlays are placed in such a manner that the different parts of the form will make the proper impression on the sheet of paper when the press begins to print. Another impression is then printed, and after it is approved, the pressman sets the fountain, which will feed the ink evenly to the rollers, and the jogger, which is an automatic device for straightening the printed sheets into even piles. A device which dries the ink on the paper by means of gas or electric heat is attached to the press. One of the duties of this worker is to see that it functions properly when the press is in motion.

The cylinder-press feeder feeds the sheets of paper when a comparatively small number is to be printed. When a long run is planned, an automatic feeding device is attached which picks up the sheets and places them in position as marked by the guides. They then pass through the press automatically. The feeder assists in preparing the press for operation, cleans and oils it, washes the rollers, and makes adjustments under the supervision of the pressman who must watch his machine to see that it runs properly all of the time. When the automatic feeder is in use, he must watch the feeding mechanism and he must keep it supplied with paper.

It has been stated above that there are several types of rotary presses. This type differs from the others in that it has two cylinders, one of which carries the form which is a curved plate, and the other carries the packing. These presses are used for a variety of purposes, but especially for magazine and newspaper printing. The plates are made either by the electrotype or the stereotype process, depending upon the purpose for which they are to be used. Usually electrotype plates are used in magazine printing, while stereotype plates are used in newspaper work. A newspaper rotary press is composed of a number of units, each of which prints one part of the edition. Some of the largest of these have as many as twenty units. They are connected in such a way that they can operate together to print a newspaper with as many as sixty-four pages in one issue. In the magazine printing with the rotary web press the process of making ready is somewhat similar to that which is necessary on the cylinder press. No make-ready is required on a newspaper press, the packing, which is a soft feltlike substance, being changed at regular intervals. There are a number of different types of rotary presses for newspaper work, but all of them are constructed on the same principle.

While the men who work in a newspaper pressroom are not required to make ready, they have other duties to perform before the press is ready for operation. They remove the plates which were used on previous runs; they wash the rollers; and they clean all the parts of the press. They get the rolls of paper ready for printing, and they lead the web back through the various rollers. Then they place the plates in position and lock them up, and the press is started slowly at first until all adjustments are made. After this is done, the press is allowed to run at full speed. One web pressman is in charge of several units, and he supervises the work of other web pressmen and apprentices. Some of them oil the press while it is in motion, others handle the rolls of paper, and one man watches the tension of the web to see that it does not break. The apprentices or flyboys assist in the operation of the press, take away the plates of previous runs, bring in the new plates if there is no automatic delivery system, help to clean up the press, and remove spoiled sheets and newspapers. Many newspaper pressrooms have conveyor systems attached to the presses by means of which the newspapers are carried to the mailing room. When the conveyors are not attached, the flyboys must take the newspapers from the press.

Color printing is also done in newspaper pressrooms. In this type of work, the pressmen must be careful to place the plates on the cylinders so that they will make impressions on the web in the right positions. This is very important and requires a considerable amount of work. The other operations are similar to those which are performed in the printing of the newspaper in black ink.

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