Depending on how a job is to be bound, there are certain ways that pages need to be laid down (imposed) for folding and finishing.

Example of a saddle stitched book printed by Printhouse
The most frequently used method of binding jobs is probably saddle stitching – in reality, this usually means folding sections together and fastening them through the spine with (usually) two metal staples. For this method of finishing, sections need to be ‘collated’ together i.e., folded and then placed one inside the other, so that the staples holds all the sections together at the spine, and close on the ‘centre-spread’. This means that all saddle stitched jobs must contain a number of pages that is divisible by four (since the smallest section that can be included will be one double sided sheet folded to the same size as the finished job – which will by definition have four pages.) In reality, most printers will impose multiple pages on larger sheets, positioned to make it possible for the sheets to fold and collate together as larger sections – frequently 8, 16 or 32 pages per section (which is why printers’ prices are often more favourable when working with these multiples). This often means that sections can contain pages that are not intended to appear together in the finished booklets, which can be confusing if you are new to viewing printers’ proofs. (On a 32pp job, for example, page 1 will face page 32, 2 will face 31, and so on, with the number of pages per section determined by the page size and the size of the sheet the printer will be using.)

Example of a perfect bound book printed by Printhouse
For perfect or PUR bound jobs the sections are folded in a way that appears similar but has two important differences. Firstly, since the books are bound with glue at the spine, a binding margin needs to be allowed so the spine can be milled off and glue introduced to the milled edge. And secondly, the folded sections are ‘gathered’, one on top of the next, as opposed to collated (one inside the next) as used in saddle stitching.

Example of a thread sewn book printed by Printhouse
And the third method frequently used is threadsewing or section sewn binding, frequently used with hard backed or case bound books. In this case the sections are in fact sewn through the spine with thread, but then they are gathered in the same way as perfect bound books (one on top of the next) to form ‘book blocks’ (meaning blocks comprising all the text of one finished book) which is then cased in with the covers and endpapers to create the finished book.
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As you can see, we have extensive experience of producing professionally printed books, brochures, catalogues… in fact, every kind of printing. No matter how your pages are gathered together, we can professionally design and print your item. Get in contact today for help, advice and a print quote:
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