Perfect Binding Requirements

Here are some guidelines for a great perfect bound project.

Text Specifications

We recommend a spine grind of 1/8” – 3/16” for most projects. Hand feed projects (digital) can get by with a smaller grind. Folded signatures – especially 32pg+ may require more grind to get into the inside spread. We can take off up to ¼” but we’d like to approve the project in advance if you are considering.
We recommend a 1/8” bleed on the head, foot and face of text.
Use a light perforation on the spine and head folds to allow the signatures to lay flat.
The first and last page of text should have 3/16” clear for side glue.
If your project requires a 2 page we recommend that it be between signatures. Placing a 2 pager or fly sheet at the front or back is a slower, more expensive project and may result in higher spoilage.
Folded signatures should be stacked high-folio up, please.
No lap is required for perfect binding.
The maximum thickness of text is 2.3125”. The minimum thickness is 0.060”. For all books with text under 0.07 we request that sample mill-run materials be sent in for a feasibility test.
Thin books can have slightly rounded spine.

The cover must have glue traps for all PUR projects, and glue traps are recommended for all books. The trap should extend beyond the foot of the untrimmed text by ¼”. The head should have 1/16 available. This is sometimes referred to as a “soft head”.
Unfortunately, it is common for covers to be imposed too close together (or too close to the edge of the sheet), requiring a reprint. Nobody is happy when that happens.
Heavy covers, heavy ink coverage and some digital print are prone to cracking. Potential solutions include lamination, letterpress scoring and flood UV. Costs for these services are not included in bids unless explicitly stated.
The inside cover must be free of coatings and inks in the spine area (after grind), plus 3/16” for the side glue.
Unless requested, all perfect bound books will be produced with a ¼” hinge score. Be careful to include this when doing cover layouts.
Best results come from having the grain run parallel with the spine. Grain wrong text can cause wrinkles. Grain wrong covers may crack and / or require an LP score. LP scoring is not included with most bids unless explicitly stated.

The maximum width of a perfect bound book is 11.75” after the 1/8” face trim.
Regardless of book size, the cover needs to be at least 8.5 face-to-face (flat) to feed into the binder.
The minimum width is 2.75” spine to face after trimming.
Minimum height is 4.25” head to foot, but books can be bound in a 2up format and then trimmed apart.
Larger books can be produced using drill-and-lace techniques.
Puget Bindery does not provide the width of a spine based on paper specifications. If you send in sample materials we will provide a “rule up” of the spine score location. For a small fee we will also produce a dummy book,