FORWARDING: Rounding & Backing
The sections are now knocked up again, particular attention being paid to having the book quite square at the back and at the head. It is then laid on the edge of the bench between two pieces of mill hoard which come up flush with the backs of the sections, the cords being quite covered by the boards. A thin coating of hot glue is now applied, pressure being made on the upper mill board in order to keep the glue from penetrating between the sections. Always apply the glue from center of back, toward head and tail.
Now (allowing a short time for the glue to set) lay the book on a large lithographer's stone (Or on the bench) with the fore edge toward the operator. By placing the left hand flat on the upper surface, thumb against fore edge of central sections, the upper sections may be drawn toward the front, tapping the back in the meantime with the backing hammer, which causes the upper half of the book to assume a rounded shape.
The book is then turned over and the same process gone through with on the other side and repeated until it is "rounded" properly (the glue used for this purpose is especially prepared and does not become as hard and unyielding as the ordinary article). The back now being "rounded," the book is laid on the bench, back away from the operator.
Take one of the backing irons, slightly moisten its surface, place it on the book from one-sixteenth to one-eighth of an inch from the back edge; holding the book and the iron firmly together, turn them over and adjust the other iron, moistening it also. The edges of the irons should be quite parallel. The distance from the edge of sections depends altogether upon the thickness of the book and the proposed thickness of the cover. After having adjusted the backing irons, hold them tightly, so they will not become disarranged, and place in the lying press; great care being taken to keep them perfectly parallel. The press is then screwed up as tight as possible. The cords rest on the outer side of each backing iron and care must be taken not to strike them with the hammer, else they will be cut off. With the front edge of the backing hammer (the operator standing beside the press) the sections are knocked away from the center line of back, on each side, by tapping them gently. [backing.jpg] After this has been carefully done, the face of the hammer is used (the operator now standing at the head of the press) and with blows directed alternately toward each edge of the back, the sections are gradually beaten over to the left and to the right, this finally resulting in the sections on each side being beaten down, overlapping the sharp edge of the backing irons. When finished the back of the book should be perfectly round and solid. Taking the book out of the press, we find that we have formed what are called "joints" which should be just deep enough to take in the thickness of the the board which it is proposed to use for the cover.
Putting in boards: The thickness of board appropriate to the book having been selected before the backing is done, they must now be cut to the proper size. Before doing this, each board is lined (if this has not yet been done), either on one or both sides with ordinary thin white paper. They may be lined only on one sidein which case one thickness of paper on one side only is sufficient. Again, they may be lined on both sides, in which case two thickness of paper are put on one side and one thickness on the otherthe side lined with double thickness forms the inside of the cover. This results in drawing the board on one side, the curved side always forming the inside of the cover. This drawing is necessary in order to offset the drawing qualities of the leather when it is put on the outside of the board in the process of covering.
After the boards are lined, and have become thoroughly dry, they should be cut to the proper size. Measurements for the covers should be taken before backing as follows: The book lying on the press, with the back toward the operator, the thumb-nail is placed against the back edge. With a compass (one leg resting against the thumb-nail) the distance from the back edge of the section to the front is taken. This constitutes the width of the board. Turning the book with the head toward the operator, and placing the thumb-nail against the head, the distance from the head of the section to the tail is then taken in a similar manner. An allowance is made for the "square" at the bottom of the book, which ranges from one-eighth to three-sixteenths of an inch or more, depending upon the size of the book. This should be added to the measurement last taken and this constitutes the length of the board.
It will he noted that allowance has only been made for the "square" at the bottom of the book. The "square" at the head will be made later, by cutting the head of the book after it is placed in boards. The "square" of the fore edge of the book will be made during the process of backing, inasmuch as enough of the back edge of the section is taken up by this process to make the "square" of the fore edge. These measurements must be taken most accurately and must be accurately transferred in order that the boards may lie properly. The difference of one-sixteenth of an inch in a fine piece of work would render it very defective. The best way to transfer these measurements is to register them on a narrow strip of firm, substantial paper, the lines being made with the sharp edge of a bone folder.
It is always best to cut the two covers at one operation, the two boards being kept together while the four edges are being cut. All boards should be cut most accurately in the cutting press. Lay them out with an accurate steel square, and mark with knife-edge. In order to ascertain whether they are absolutely true after cutting, one board may be reversed on the other, so that the ends which were cut together are opposite each other. If there is the slightest difference in the two boards, this method will increase it so that it will be quite noticeable. If there is any material difference, it is better to cut a pair of new boards than to try to trim up the old ones. In all cases the boards should be cut with the lined sides in contact and should be marked on the inside so they may be placed in the same relative position when lacing them to the back. The boards may he laced on after cutting the back edge only, the remaining portion being cut to size after, just before putting in leather. I prefer the former method.