There are many other forms of press by which great pressure can be applied, some working by various arrangements of cog-wheels, screws, and levers, others by hydraulic pressure.
Trimming Edges before Sewing--Edge Gilding
When the sheets come from the press the treatment of the edges must be decided upon, that is, whether they are to be entirely uncut, trimmed before sewing, or cut in boards.
Early printed books and manuscripts should on no account have their edges cut at all, and any modern books of value are better only slightly trimmed and gilt before sewing. But for books of reference that need good bindings, on account of the wear they have to withstand, cutting in boards is best, as the smooth edge so obtained makes the leaves easier to turn over. Gilt tops and rough edges give a book a look of unequal finish.
If the edges are to remain uncut, or be cut "in boards" with the plough, the book will be ready for "marking up" as soon as it comes from the press; but if it is to be gilt before sewing, it must be first trimmed.
The sheets for trimming with end papers and all plates inserted must first be cut square at the head against a carpenter's square (see fig. 7). Then a piece of mill-board may be cut to the size, it is desired to leave the leaves, and the sections trimmed to it. To do this three nails should be put into the covering board through a piece of straw-board, and the back of the section slid along nails 1 and 2 until it touches No. 3 (see fig. 23). The board is slid in the same way, and anything projecting beyond it cut off. When the under straw-board has become inconveniently scored in the first position, by shifting the lower nail (1) a fresh surface will receive the cuts. Fig. 24 is a representation of a simple machine that I use in my workshop for trimming. The slides A A are adjustable to any width required, and are fixed by the screws B B. The brass-bound straight edge C fits on to slots in A A, and as this, by the adjustment of the slides, can be fixed at any distance from B B, all sizes of books can be trimmed. As by this machine several sections can be cut at once, the time taken is not very much greater than if the book were cut in the plough.