Fig. 57—Section of edge rule.
For shaping boarded books an edge rule is used. This is a thin iron rule not much longer than the width of the book. On the long edge an iron pin about the width of the edge is soldered. This tool is inserted between book and board so that the iron pin lies close to the edge of the book; if the board is trimmed along this it will leave the board exactly as much larger than the book as is the width of the rule.
Knives or points must be well grasped in cutting boards. The edge must be clean and square.
If the boarded book has a hollow back, first one end is shaped and the projecting back is neatly cut clean and straight to the other board with the shears, and then the other end is shaped.
Boards are fixed on a deep groove by pasting them on the outside to a width of about 3 cm., placing them direct on the book, backing them firmly into the groove, and then pasting the bands very smoothly upon the boards. A folded piece of waste paper is placed on the pasted part, a piece of zinc plate over it, and the book then pressed. The double leaf is used to prevent any sticking to the zinc plate, which bands are particularly liable to do if the plates had not been properly cleaned after previous use.
Boards to be fastened into a deep groove must be lined with waste paper; this is done with paste. When packing, a narrow strip of paper must be brought over the inner edge of the board in the groove to the outside, so that the cut edge of the board is covered and does not strain or swell.
This is also done when boarding, as follows:—
At the present time, all good half or whole leather bindings have the boards laced through in good shops. At the outset the bands must be left with longer ends for this—5 cm. at least on each side. A parallel line is marked on the board along the back about 6 to 8 mm. from the groove. The board is fitted on the book just as was done when fixing in the groove, and exactly opposite each band a point is made on the marked lines. The board is then removed and at the points marked is pierced slanting inwards—about half right angle—with a pointed awl. The board is turned, and sideways, near every first hole, a second hole is made which likewise takes a slanting direction to the board. The bands are drawn through these holes, and to be able to do this the bands must be well pasted and twisted to a point; cutting off the extreme ends of the bands will facilitate the drawing through. To draw the bands quite firm and tight the boards are stood upright in the groove, the bands drawn through as tight as possible, and in this position—that is, with the boards half open—they are knocked down with a hammer upon a firm bed. The principal thing to be observed is that the bands are pasted fast in the holes, but where they are seen they are knocked down quite flat. The boards are now slowly closed, the ends of the bands projecting at the outside are cut off short, and the book pressed, using zinc plates inside and out.
Fig. 58—English style of lacing boards.