Book manufacturing in the modern world 2

Some books, particularly those with shorter runs (i.e. of which fewer copies are to be made) will be printed on sheet-fed offset presses, but most books are now printed on web presses, which are fed by a continuous roll of paper, and can consequently print more copies in a shorter time. On a sheet-fed press a stack of sheets of paper stands at one end of the press, and each sheet passes through the press individually. The paper will be printed on both sides and delivered, flat, as a stack of paper at the other end of the press. These sheets then have to be folded on another machine which uses bars, rollers and cutters to fold the sheet up into one or more signatures. A signature is a section of a book, usually of 32 pages, but sometimes 16, 48 or even 64 pages. After the signatures are all folded they are gathered: placed in sequence in bins over a circulating belt onto which one signature from each bin is dropped. Thus as the line circulates a complete “book” is collected together in one stack, next to another, and another.

A web press carries out the folding itself, delivering bundles of signatures ready to go into the gathering line. Notice that when the book is being printed it is being printed one (or two) signatures at a time, not one complete book at a time. Thus if there are to be 10,000 copies printed, the press will run 10,000 of the first form (the pages imaged onto the first plate and its back-up plate, representing one or two signatures), then 10,000 of the next form, and so on till all the signatures have been printed. Actually, because there is a known average spoilage rate in each of the steps in the book’s progress through the manufacturing system, if 10,000 books are to be made, the printer will print between 10,500 and 11,000 copies so that subsequent spoilage will still allow the delivery of the ordered quantity of books. Sources of spoilage tend to be mainly make-readies.

A make-ready is the preparatory work carried out by the pressmen to get the printing press up to the required quality of impression. Included in make-ready is the time taken to mount the plate onto the machine, clean up any mess from the previous job, and get the press up to speed. The main part of making-ready is however getting the ink/water balance right, and ensuring that the inking is even across the whole width of the paper. This is done by running paper through the press and printing waste pages while adjusting the press to improve quality. Desitometers are used to ensure even inking and consistency from one form to another. As soon as the pressman decides that the printing is correct, all the make-ready sheets will be discarded, and the press will start making books. Similar make readies take place in the folding and binding areas, each involving spoilage of paper.

After the signatures are folded and gathered, they move into the bindery. In the middle of the last century there were still many trade binders – stand-alone binding companies which did no printing, specializing in binding alone. At that time, largely because of the dominance of letterpress printing, the pattern of the industry was for typesetting and printing to take place in one location, and binding in a different factory. When type was all metal, a typical book’s worth of type would be bulky, fragile and heavy. The less it was moved in this condition the better: so it was almost invariable that printing would be carried out in the same location as the typesetting. Printed sheets on the other hand could easily be moved. Now, because of the increasing computerization of the process of preparing a book for the printer, the typesetting part of the job has flowed upstream, where it is done either by separately contracting companies working for the publisher, by the publishers themselves, or even by the authors. Mergers in the book manufacturing industry mean that it is now unusual to find a bindery which is not also involved in book printing (and vice versa).

If the book is a hardback its path through the bindery will involve more points of activity than if it is a paperback. A paperback binding line (a number of pieces of machinery linked by conveyor belts) involves few steps. The gathered signatures, book blocks, will be fed into the line where they will one by one be gripped by plates converging from each side of the book, turned spine up and advanced towards a gluing station. En route the spine of the book block will be ground off leaving a roughened edge to the tightly gripped collection of pages. The grinding leaves fibers which will grip onto the glue which is then spread onto the spine of the book. Covers then meet up with the book blocks, and one cover is dropped onto the glued spine of each book block, and is pressed against the spine by rollers. The book is then carried forward to the trimming station, where a three-knife trimmer will simultaneously cut the top and bottom and the fore-edge of the paperback to leave clear square edges. The books are then packed into cartons, or packed on skids, and shipped.




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