Hardcover book processing operations - calculation of materials (1)

Eight, hardcover book processing materials calculation method

Materials commonly used in the processing of hardcover books, including book blocks (backs of books) and book covers (including hot materials). The specifications used for these materials in processing are calculated based on the size of the book block's actual size, the thickness of the book block, and the requirements of the book's shape in processing. Only accurate calculation of processing materials can make the book block and book cover complete and accurate.

1. Material calculation method. Hardcover books and periodicals are commonly booked in several shapes such as ridges (real ridges), roundback invertebrates (false ridges), square backs, and square ridges. When determining the specifications of the materials, the same size and thickness of the open book, but different shapes of the book blocks, the materials used are also different.

In the processing of hardcover books, after the book block and the book cover are processed separately, the composite book is processed. Therefore, in the calculation, the arc length of the book back (including the ridge) is first calculated using the specifications of the book block to correctly The actual specifications for the various materials used to carry out the spine and the book case are described below. The two methods for calculating available specifications are described below.

(1) Measurement method. The measurement method is a sample of semi-finished products made by cutting, rounding or rounding up the spine of a book block. The paper back is used to measure the back corners of the book block after the round (or ridge), and it is measured directly along both sides of the spine. The actual length of the arc. If the processed book is a square back, it can be taken as the general thickness of the semi-finished book block, see Figure 3-53.

(a) Measurement method (b) Composition of half-shell book cover

Because of the thinness of the paper, the tightness of the binding, and the pressure on the books, the actual thickness and general thickness of the book block are different. Therefore, in order to use the sample in advance, the method of measuring the actual size of the book's back with a paper strip must be consistent with the size of the back of a book produced in large quantities.

(2) Calculation method. The calculation method is based on the calculation of book back thickness to calculate the length of the back of the book to obtain the specifications of the material.

According to the styling habits of hardcover books and books and the actual situation in production, the round angle of an arc of a hardcover book or a round ridge is about 130°. Then the arc it is facing is the actual circle of the booklet. Arc length. Similarly, if the thickness of the book block plus the height of the spine (ie, the thickness of the book block plus two cover sheets) is the diameter, the angle to which it belongs is still the same, and the arc is the actual length of the arc after the book block passes through the ridge. .

The calculation formulas are:

because:

130°×π/180≈2.3(rad)

and so:

L1= 2.3b1

L2=2.3 b2

Among them: b1 is half the thickness of the book block;

B2 is the thickness of the book block plus half the thickness of the cover;

L1 is the back arc length of an unrounded book;

L2 is a ridge back arc length.

When taking the thickness of the book block, do not use a book as the standard. You should take the natural thickness of the book block after it has been flattened. That is, you must not pinch the book block tightly or make it too loose. You should add more book cores. Lay flat, measure the appropriate one in the middle, or add the thickness of several books to calculate the average thickness.

2. Various specifications of commonly used materials. Hardcover books and periodicals commonly used material specifications bookback book and book shell materials. Back spine material specifications include four kinds of plug cloth, book back gauze, book spine, and bookmark ribbon (except for pictures and special materials). Book shell material specifications are rigid cardboard, cover soft material, medium diameter paper (or cardboard), in the waist material, wrapping material five kinds.

(1) Book spine material specifications.

1 plug cloth.

Length: Book back arc length (round back) or book block thickness (ie square back width).

Width: fixed size by the processing plant, generally 10 ~ 15mm.

2 book back gauze.

Length: 20mm less than the length of the book block (evenly divided at both ends).

Width: Longer than the back of the book or 40mm thick (equal to both ends).

3 book spine paper.

Length: 4 (or 3) mm less than the length of the book block (evenly divided at both ends).

Width: Book back arc length or book block thickness (can also be the same width as gauze).

4 ribbon bookmarks.

Length: ±3mm diagonal of the size of the book block to be processed.

The small 16-inch diagonal ≈ 320mm, large 16-inch diagonal ≈ 322mm.

Small 32-inch diagonal ≈ 226mm, large 32-diagonal ≈ 247mm.

The small 64-inch diagonal ≈ 156mm, 64-inch diagonal ≈ 164mm.

(2) book shell material specifications.

1 Hard cardboard.

Long: The length of the book block is plus, and the next two are wide.

Width: The book block width is reduced by 3mm (ie, the width of the book block is reduced by the width of the groove plus a wide mouth).

2 medium diameter cardboard.

Length: The length of the book block plus the width of the next two flaps (ie, the same length as the cardboard).

Width: The back of the book is long or the book is back (except for the back of the ridge).

3 comprehensive cover.

Length: The length of the book block plus two flap widths plus two wrapping widths.

Width: Two cardboard inserts with medium width and two hem widths.

4 half cover.

Medium waist length: Book block length plus two flap widths and two wrapping widths.

Middle waist width: medium width plus two joint widths (10mm per joint edge).

Surface paper length: The book block is long plus two flap widths and two wrapping widths.

Surface Paper Width: Cardboard width minus coupling edge (10mm) plus one edging width (12mm) and one adhesive edge (3mm) wide.

5 wrap angles.

The angle specifications can be determined according to the size of the book. The general specifications are as follows:

16 is about 60mm x 60mm; 32 is about 35mm x 35mm; 64 is about 30mm x 30mm.

All three types include the size of the wrapping. among them:

Medium width: Book back arc length or book back width plus two wide seams.

Slot width: Book slot width (usually 5mm) plus cardboard thickness.

Wrap width: cardboard thickness plus 10mm edging.