Hardcover book binding processing common quality problems and countermeasures (2)

4. The edge of book square after the front mouth cut uneven

cause:

1 The air in the book is not completely excluded. The pages form a wavy shape, and the wavy pages of the book are straightened.

2 When the manual folding, not suppress the book block began to scrape, leading to crease run empty, the page warping uneven, resulting in the air inside the signature can not be discharged;

3 The sewing thread is too large and the thread is too thin, causing the book page to move after being cut;

4 Do not make a round when the book is too thick.

Solution:

1 When the machine folds, it is necessary to adjust the sliding knife correctly to ensure that the air in the signature is completely eliminated;

2 When manually folding, press down on the book block and then level it to ensure that the book is folded flat and compacted;

3 Sewing machine needles are best to use fine needles to avoid the book pages running out due to the large gap between the diameter of the needles and the diameter of the needles.

4 Books with a thickness of 20mm or more are best made into round backs. Do not use them as a square back, because the square back will cause the front mouth to spit out pages when it is read.

5. After the spine ridges back, the back cracks

cause:

1 The type of glue used for the first time on the back of the book is improper or insufficient;

2 uneven coating, there are missed parts;

3 Aging adhesive, broken after coating;

4 improper use of ridges or rounds;

5扒 The cracks appear when the back of the book adhesive is not wetted.

Solution:

1 It is forbidden to use flour paste and other plant adhesives as hardcover book adhesives, and glues of bone glue or synthetic resins in animal glues can be used.

2 In the case that the adhesive's strength and viscosity are all qualified, the application should be thin and uniform, and the amount of glue should not be too much or too thick;

3 Do not use expired or aged adhesives;

4 When the ridges are used with force, they must be light and heavy;

5 should be wet when the book is back, not dry.

6. Sticking head cloth after both ends of the hair or curved, wrinkled, not straight

cause:

1 Cloth is too soft and stiff;

2 Manually sticking the head cloth does not tighten, compact, stick firmly.

Solution:

1 The plug cloth purchased must first be diluted with a thin adhesive and dried before use;

2 When sticking the head cloth, the book block should be compacted first, and then the plug should be tight and sticky after compaction.

Book Seal Processing

Book cover processing includes shell and hot stamping two parts.

1. The rounded corners of the book shell have rough corners

1 improper method of plug angle;

2 too few creases in the corner;

3 After the plug angle is not compacted.

Solution:

1 can be used oblique, long handle, not sharp metal knife (such as students with a pencil sharpener, etc.), or use the thumb nails to manually plug the corner, can also be used angle machine plug angle;

2 The more creases behind the plug angle, the better, but not less than 50%;

3 After using a hand-plug angle, use a wooden hoe to pry the horns and flatten them.


Source: pack.cn