Perfect Bound Specifications and Guidelines
- Allow 1/8”-3/16” grind off spine of signatures.
- Use light perforation on head and spine (please do not over perforate which could create gathering problems with signatures pulling apart).
- Allow ¼” head, ¼” face, and ¼” foot trim. Bleed in the appropriate bleeds 3/16” into the trim. Note- These trims can be adjusted to accommodate web cut offs and different sheet sizes. Please advise if different trims are needed.
- On first page first signature and last page last signature, mask 3/16” area free of links and coatings beyond the 1/8” grind for side glue application.
- Mask back inks and coatings 1/16” on all other pages (excluding the first page and last page) beyond the grind off. This is done so that there can be better glue adhesion to text stock.
- Signature can be folded without a lap.
- Grain of text should run parallel to binding edge.
- Maximum signature size, front to back, cannot exceed 12 ½ inches.
- On very thin books (1/8”) spine may have a slight rounded effect.
- Grain of cover must run parallel to binding edge.
- Gatefold should be well secured with head and foot tack falling beyond the trim size. Gatefold should be a minimum of 1/8” short of face trim. Note- In some instances the tack is not needed. Please consult on a job-by-job basis.
- One-up cover to equal untrimmed signature size head to foot plus 1/8” head and 1/8” foot for glue trapping. Please match trims and bleeds with signatures.
- Minimum flat cover size for a perfect bound book must be at least 9-1/2” left to right.
- On inside of cover if printed, please mask back inks and coatings where spine and side glue adheres. This dimension will be the bulk of book plus 3/16” front and 3/16” back for side glue.
- If covers are UV coated, please note that you may experience some enhanced cracking of coating where spine wraps book as well as where cover hinges.
- For any special specifications such as gatefolds, foldouts, special coatings, etc. Please call for further guidelines.
- On hardcover books spine can be square or round back.
- End leaves should be .006 (80#uncoated) or thicker on hardcover books.