How to calculate the spine thickness of a book

How to calculate the spine thickness of a book

In the practice of publishing and printing work, the issue of book back thickness is often involved, such as the setting of text size on the back of a book, and we often encounter the phenomenon of "text or small images on the back of the book not being in the middle". In production, the thickness of books is often calculated using the following methods.

(1) The calculation of the thickness of the back of a regular paperback book is that the book thickness is equal to the thickness of one sheet of paper multiplied by the number of sheets (or page numbers divided by 2).

For example, if Book A is printed on 55/m2 paper with a total of 512 pages and each sheet has a thickness of 0.08mm, then the thickness of this book is: 0.08mm × 512/2=20.48mm.

(2) Calculation of Back Thickness for Hardcover Books

① The thickness of a hardcover book with a square (flat) back is equal to the thickness of the book's paperback (book core)+the thickness of the front and rear lining (the thickness of each lining paper multiplied by 4)+the thickness of the cardboard (the thickness of each cardboard multiplied by 2)+the thickness of the book cover fabric (the thickness of each fabric multiplied by 2).

For example, suppose a book B has the same thickness as in the previous example, with 180g/m2 adhesive paper used for the front and rear ring liners, each paper having a thickness of 0.15mm. The book cover is made of 2mm thick cardboard, and the book cover fabric is coated with plastic paper, each paper having a thickness of 0.3mm. The thickness of this book is 20.48+0.15 × 4+2 × 2+0.3 × 2=25.68

② The thickness of a hardcover book with a round back actually refers to the length of the arc on the back of the book. Generally, the arc of this arc is 120 degrees, and the chord corresponding to this arc is the thickness of the straight line (square back thickness) of this hardcover book. At this time, the ratio of chord to arc is 1:1.15.

For example, if the hardcover book B is made into a round back hardcover book C, then the thickness of book C=the thickness of hardcover book B × 1.15=25.68 × 1.15=29.53mm.

How to calculate the spine thickness of a book

(3) Empirical calculation of book thickness in printing factories (for rough estimation of book thickness only)

0.135 x grams/100 x pages (note: pages are not page numbers)=spine thickness (in millimeters),

For example, a book printed on 55g/m2 paper has a total of 512 pages and a thickness of approximately 0.135 × 55/100 × 512/2=19.008mm.

How to calculate the spine thickness of a book