The boards may be fastened to the covers in various ways, apart from casing, i.e., fixing books in publishers' ready-made cases.
1. Fastening upon bands (ordinary fastening).
2. Fastening below bands (fastening on a deep groove).
3. Drawing the bands through the boards (fastening with laced bands).
The boards for the books are nowadays manufactured from pulp, excepting in a few districts in Pomerania and East Prussia where wood boards are still occasionally made. Of these pulp boards the better kinds are called mill-boards; the cheaper are called straw-boards. Leather boards are not suitable for books as they invariably wrinkle or cockle. The boards may be cut to size before fastening on, or this may be done even after the fastening on has been completed. The former is generally practised where there is a board-cutting machine, but even then further attention is usually given to the shaping of the boards in the case of "extra" work.
The board-cutting machine is a very useful ally, for by the aid of quickly adjusted rectangles and parallels a board may be cut perfectly true.
The boards are selected according to the size and thickness of the book, marked out, and cut perfectly rectangular. The boards must slightly project at top and bottom as well as fore-edge so as to afford sufficient protection to the book. The margins so projecting are called the squares. Small books are allowed a small square, as a matter of course, and large books a square correspondingly larger.
Fig. 54—Board-cutting machine.
Where there is no board-cutting machine, the boards must be cut to size with the knife upon a cutting-board, using a straight edge for the line.
The knife used is the well-known bookbinder's knife—Henckel Bros.' Solingen make is the best. These knives—both in fixed and removable wooden handles—are made of "glass hard" steel. If the point is worn away, a piece about 1/2 cm. long is knocked off with a hammer on an iron edge, thus making a fresh edge. The cutting-boards must be of maple, beech, or pear tree.
If it is intended to shape the edges of the board on the book, it must be cut about 1 cm. larger each way so as to allow for further trimming.