Estimating the thickness of a booklet's spine (Back edge)

Note that the length/size of a cover sheet depends on the thickness of the book block's spine.

The following list shows examples for A4 size or Letter (8¹/₂ × 11), 80 g/m² (20 lb. Bond) (10-micron) paper:

• 10-sheet book block: 1 mm (0.04 inches)

• 30-sheet book block: 3 mm (0.12 inches)

• 50-sheet book block: 5 mm (0.20 inches)

• 80-sheet book block: 8 mm (0.32 inches)

• 100-sheet book block: 10 mm (0.40 inches)

• 200-sheet book block: 20 mm (0.80 inches)

Specify the cover sheet size based on the thickness of the book block's spine. Use the following equation to calculate the length of the cover sheet:

Minimum length of cover sheet (mm/in) = "length of book block sheet (mm/in)" × 2 + "thickness of spine (mm/in)"

To perfect bind a booklet of the following dimensions, specify a cover sheet length of 440 mm (17.4 inches) or longer:

• 200-sheet book block: A4 or Letter (8¹/₂ × 11)

• Spine thickness: 20 mm (0.8 inches)