Back: The flared hinge ironed onto the text portion of a case bound book by a rounder-backer. The back serves several purposes: 1) it holds the round in the text 2) it keeps the cover boards in position after the book is cased in 3) it creates a hinge together with the case that helps each page to bend in the paper rather than at the binding, reducing stress on the binding and making the book last longer.

Backbone: See spine.

Boards: The stiff recycled paperboard that supports the cover cloth to form the case. Can be either Davey board, which is made of a single layer of calendared pulp, or chipboard made up of several layers of pulp pasted together, or any of several other types of board. Boards were once actual slabs of oak in the good old days. See also Davey board, chipboard.

Book Cloth: See Cover Materials: Cloth Grades

Buckram: See Cover Materials: Cloth Grades.

Bundling: Pressing and storing folded signatures between boards to flatten folds and prevent wrinkles and waves that may appear due to changes in temperature and humidity.

Case: The cover of a case bound or hard cover book, made up of a front and back cover board, a piece of material to support the spine, and the cover cloth or paper.

Cover Materials: Cloth Grades: Various woven cloths for use as book cover materials have been graded A through F by NASTA (The National Association of State Textbook Administrators), AAP (The Association of American Publishers) and BMI (The Book Manufacturers Institute) and codified under ANSI L29.1, 1977.

• A, B, C, C-1, D, E, and F grade cloths are woven fabrics, usually cotton, with a Pyroxylin or aqueous acrylic coating. A grade cloth uses the thinnest yarn, and F grade the thickest. The D, E, and F grade cloths are usually referred to as "buckrams." Manufacturers are gradually moving away from Pyroxylin coatings, which use noxious solvents, to water-based acrylics.

Cover Materials: Types I and II cover material

The Type I and II classifications were developed as manufacturers invented less expensive alternatives to the A-through-F grade cloths. Type I and II cover materials can be used as turned edge type materials, self supporting covers for soft cover books, or endsheet/side panel materials, depending on thickness and coating. They are often printed using conventional lithography.

• Type I cover materials have a paper base, and may have resin (but not latex) reinforcing. They may be coated or uncoated, colored, or white for offset printing.
• Type II cover materials are latex reinforced, and come in two grades: "non spec" which does not meet all Textbook (NASTA/National Association of State Textbook Administrators) specifications, and the "spec" grade which does.
• Type III cover materials are synthetic bases, such as Tyvec. This classification is now rarely used.

Chipboard: A board made up of pasted layers of pulp. Used for the cases of hard cover books, as well as spines, hubs, etc., chipboard is less dense than Davey board but comes in similar thicknesses.

Collate: To arrange signatures or pages in order.

Crash Paper: Attached at the backlining stage of production of a case bound book, crash is normally a kraft paper applied over the super; it adds strength to the spine and covers the glue saturating the super. The head and tailbands will be attached to the crash paper in the backlining machine before this assembly glues to the spine of the book.

Davey board: Bookbinders board made from recycled paper fibers, produced by the Davey Company. A single layer of pulp is calendared to various thicknesses and densities, from .059" to .147". Used for the case of hard cover books. See also case.

Deboss: To stamp in such a way as to leave a depressed area on a finished piece. Foil stamping the covers of case bound books normally laves a debossed area as well as the transfer of foil. This deboss can be done without foil to create a "blind deboss." See also emboss.

Dust Jacket: A paper wrapper placed around the hard cover of a finished book. Often printed with bright, appealing colors and images to attract attention on the shelf.

Emboss: To stamp in such a way that a raised image is left on the finished piece, usually with a die and a counter. See deboss.

Endsheets: Four-page sheets of paper (sheets with a single fold) attached to the outside of the text portion of a case bound book. The endsheets glue to the inside of the boards that make up the case. Since one side of each endsheet is covered with glue when the books are cased in, it is critically important that the stock is 70 lb. or heavier uncoated book, and that the grain runs parallel with the fold. Straying from these guidelines can cause wrinkles as the glue-moistened paper swells.

Foot: The bottom of a book when looking at the front cover, the bottom of each page.

Fore-edge: The opening edge of a book; the right hand side when the closed book is viewed from the front.

Forwarding: All of the steps in binding a hard cover book between sewing and casing in, including smashing/gluing, rounding/backing, and backlining.

Grain: The pattern of fibers in paper, board, and other materials. During manufacture, most fibers will line up parallel to each other resulting in a predominant grain direction. Grain direction influences the strength of paper and board and has implications for folding, gluing, etc.

Grind Off: An area composed into the spine edge of each signature for a perfect bound book, usually 1/8." The perfect binding machine will saw off this portion of the spine edge of the text block. This ensures that every sheet in the book has a well-prepared edge to receive glue.

Head: The top of a book when looking at the front cover, the top of each page.

Headbands: also tailbands. Decorative ribbons attached to the head and tail (foot) of the spine of a case bound book. In medieval times, head and tailbands were an integral part of the hand-sewn construction of a book.

Head trim: The distance between the edge of a sheet or folded signature and the final trim at the head of a book. Minimum 1/8", often 1/4." It is critical that the binder knows the correct head trim, as well as the trim size, to deliver books as they were designed.

Hinge: The joint of a case bound book; the gap between the front and back cover boards and the spine which allows the cover to open.

Hot melt: Any of a number of adhesives used in perfect binding machinery. Applied at 300-400 degreesF, solid but flexible at room temperature.

Hubs: The ridges produced on the spine of a book that has been hand sewn. Sewing a book on cords leaves raised bands of twine running across the spine, and these hubs are visible from the outside of the finished book. These days, hubs seen on machine sewn books are for decoration only, made by inserting small pieces of chipboard in the spine portion of the case.

Impose: To lay pages out on a large sheet for press. Imposition is critically important for the binding as it will determine how the printed piece will (or will not!) fold.

Joint: See hinge.

Lip: An overhanging extension designed into a signature to facilitate opening it to the spine on a sewing machine. Usually a "high-folio" lip is specified, which means that the back half of the signature, with the higher folio (page) numbers, should be longer than the front half. Lips should normally be at least 1/4".

Oversewing: Side-sewing done with an oversewing machine. The machine punches and sews small lifts of single sheets approximately 1/8" at a time.

Perf: Short for perforation. See our Frequently Asked Questions page.

Reinforced endsheet: For exceptionally heavy use, a fabric tape can be glued around the outside of an endsheet and signature as they are tipped together. This tape covers the entire length of the signature and will be sewn through to add strength and long life to the book.

Round: The curve forced into a case bound book by a rounder-backer, forming a concave fore edge.

Round Back: A case bound book that has a curved text and cover, with the fore edge concave and the spine edge convex. Made by running the trimmed text through a rounder-backer.

Sewn On Tapes/Strings: Usually done by hand, but also by some specialized machines, a Smyth-type sewing process that not only links each signature to the next, but sews through a fabric tape or around a string to add strength.

Side sewing: Sewing done by hand or machine across the back of a book's text, rather than through the backbone of each signature. Usually used to bind books made of single sheets rather than folded signatures. Holes are either punched or drilled along the spine edge of the text, then thread or a flat fabric tape is laced through the holes.

Sig.: See signature.

Signature: Normally refers to a large press sheet that folds and makes up a portion of a book. Signatures can be 4, 8, 12, 16 , 24, 32 pages or more. Even a single sheet, however, can be considered a "2-page" signature.

Slipcase: A box, usually cloth-covered board, which holds a book or set of books, leaving the spines exposed to view.

Smash/glue: Book text blocks are smashed, or pressed, in hydraulic clamps to flatten the folds and press out the swell caused by Smyth sewing. This is followed by an application of glue to the spine portion of the block, which keeps the sewing from unraveling, and stiffens the spine enough to allow it to be trimmed without shifting. This "first coat" of glue also holds each signature tightly against those next to it so that the binding will be invisible once the book is finished.

Smyth Sewing: A machine sewing system developed by the Smyth Manufacturing Company. Signatures are sewn through the spine fold with several stitches that hold the pages together after trimming. Each signature is linked to the next. Since there are now many brands of sewing machines, the proper terminology is "signature sewing".

Spine: The bound edge of a book or its cover.

Square: The overhang designed into a case bound book by making the boards of the case slightly larger than the text trim; usually 1/8".

Square Back: also called flat back. A case bound book bound without rounding or backing. The text remains flat, as it came from trimming. A piece of board will be put in the spine portion of the case to hold the book square, instead of the flexible paper used to allow round back cases to conform to the curved text.

Stamping:Also foil stamping, blind stamping. Producing an image on the cover of a book using a raised die to deboss and area, with or without foil.

Super: A stiff, open-mesh fabric attached as part of the backlining process of a case bound book. The super extends past the spine on front and back so that it will glue to the case with the endsheets when the book is cased in. The super does the lion's share of the work holding the text of the book to the case.

Three-Piece Case: The cover of a hard cover book made from three pieces of material rather than one. The spine is covered with a different material than the front and back covers or "boards." Usually the spine will be covered with a cloth or other material strong enough to act as the hinge of the book, and the boards with a less-expensive paper.

Tip: To attach with a thin bead of glue. Since 4-page signatures and single sheets cannot be Smyth sewn, endsheets, 4-page and 2-page signatures, plates, etc. are tipped to other signatures in a sewn book.