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p:press [2018/03/30 02:07] (current)
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 +<< [[contents:​index| Dictionary Index]] << [[contents:​p|Definitions under P]]
  
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 +====== Press ======
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 +The machine by means of which a printed impression of types and engravings in relief is obtained. ​
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 +It is a curious circumstance,​ that from the first introduction of the art of printing in Europe, about 1440, till Earl Stanhope made a great improvement,​ the principle of the press remained the same, and even the construction of it underwent little alteration. The principle is simple; a level surface attached to the end of a screw, by which it is pressed upon the types with a sheet of paper interposed to receive the impression. The improvements that Lord Stanhope introduced were an increased power, by means of a compound lever attached to the screw: this increased power was the means of producing larger presses, which enabled the printers to print larger sheets of paper than before, with one pull, even to the extent of a double royal; and these new presses, being made of iron, produced better workmanship than wooden ones, with less trouble, the wooden platen being subject to be indented, which occasioned the impression to be irregular; this required much time and trouble to equalize it, particularly in fine work. This iron platen wears out types sooner than the wooden platen. Many of our most splendid books were printed with wooden presses. For some account of the most approved iron presses, see under their respective names. ​
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 +Although there are but few wooden printing presses now made, iron presses having superseded them, yet, as there are many still in being, it may be useful to retain the knowledge of fixing them in a proper manner, on which account I shall give an old pressman'​s directions for this purpose. ​
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 +"//To erect a Press// — The feet must be horizontal, and the [[c:​cheeks|cheeks]] perpendicular;​ then put the [[c:​cap|cap]] on the cheeks, and fix the stays as firmly as possible between the cap and a solid wall, or a strong beam: while the joiner is doing this, the pressman rubs well with black lead the tenons of the head and winter, the mortises in the cheeks, and all other parts where friction occurs. Place the winter horizontally,​ and on it put the [[c:​carriage|carriage]] which contains the ribs; the joiner shortens or lengthens the fore stay under the carriage till the ribs become horizontal; lay the [[c:​coffin|coffin]] on the ribs; [[b:​bed|bed]] the stone, which is a very particular point, as it must be perfectly horizontal, and ought to be of equal thickness, and as smooth on the under side as on the upper surface, so that if the face should be at any time so indented as not to be fit for work, the same stone will do by turning it over, and occasion very little trouble in bedding it, and will not be so liable to break in working down as a new one. Cartridge paper is the safest bedding, and stout tape laid even under the stone is preferable to cords, as I know it is a preventive to the stone breaking; and after it is bedded, the ends of the tape are easier put between the coffin and the stone than cord. 
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 +"The head being put in, and the [[b:​box-2|box]] with the spindle in it, fix the shelves; then fix the platen; this must be done so exact as to touch the face of all the type at one and the same time: the way to know this, is by cutting four narrow slips of paper about six inches long, and, taking care that there is no dirt on the stone nor on the bottom of the [[f:​form|form]],​ plane it well down, place the four slips of paper, one on each of the four corner pages; bring down the platen so gently, that the corners of it may barely touch the slips of paper, with very little pressure; if they all bind alike at one instant, the platen hangs right; if not, alter the fixing till they equally bind. 
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 +"The rounce being set, and the upper and under bolsters made, the pressman lays on a heavy form without [[b:​blank-pages|blank pages]], if he can get one; and if it be a new press, he brings down the bar to the near cheek regularly, until the press be properly wrought down. As he goes on, the new scaleboards work close, and cause the press to lose power; the pressman must continue adding more, until there be a sufficient quantity in the head. If it be really necessary, put some scaleboards under the winter, but the fewer the better. Pieces of felt hat are preferable to scaleboards for loading the head of a press. ​
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 +"I have always found the least slurring in presses that have solid fixed winters, and have often abolished slurring and mackling in old presses, by taking out all the scaleboard from beneath the winter, and substituting solid blocks of wood. The mortises which contain the tenons of the head ought always to be made long enough to contain all the spring that is necessary for a good press. ​
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 +"​Attention being required, and much time lost in working down a new press, two guineas are paid for doing justice to it." ​
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