The turned-in cover is turned and the front side well rubbed down under paper with the folder. When cloth has once been glued it must not be allowed to lie long as it rolls up and sticks together, which renders it practically unworkable.

The finished covers are laid between pasteboards to dry; only when the drying has to be done in a hurry may they be hung on stretched cords.

The latest in this work is a case machine which turns out 550 cases per hour.

When leather is used, it must first be pared, that is to say, the parts to be turned in where it is too thick in the joint must be gradually thinned.

Fig. 62--Paring with Offenbach or Berlin knife.

The paring knife, of which there are various kinds, is used for this work. The best known and the most generally used are the Offenbach and the Berlin, both very much alike except for a slight difference in the edge. The quickest paring knife is made after the French pattern.

This knife is called a "thrusting" knife because of the manner of using it, in contradistinction to those generally used with a cutting motion; but even these a skilful worker will be able to use with a thrusting motion. The under side of the paring knife is covered with leather.

A lithographic stone or piece of marble will serve as a bed upon which to pare the leather. The stone is set in a frame under which there is a bar to hold it against the edge of the table so that it does not work backwards whilst in use. All edges are rounded off and the surface is ground and polished.

Ability in paring does not entirely depend upon the skilful use of the knife but also upon the way the left hand manipulates the leather and upon a thorough knowledge of the nature of the leather. It should not be forgotten that the latter has a grain, though very few bookbinders pay any heed to this. With many leathers it is a very difficult matter to pare against the grain, especially pig-skin and cow-hide. One may generally take it that a leather pares best in the direction in which it stretches least. The grain runs from the back to the sides. The Offenbach knife is narrower and ground more to a square point than the Berlin knife, the edge of which forms a sort of half right-angle to the blade. See manner of holding the knife in Fig. 62.

Quick working is an advantage of the Offenbach knife, which is due to the fact that less attention need be given to holding the leather on the stone, and paring proceeds from left to right, the left hand at the same time helping to push the knife. The Berlin make pares from right to left; here the blade is held almost parallel to the edge of the leather, the point of the knife inclining to the leather; with the other the edge is cut over slantingly with the point outwards.

To use the French knife requires more practice; the cutting edge is almost at right angles to the knife, and, besides, the method of holding it is somewhat unusual. For paring all thick leathers or large surfaces it surpa.s.ses all other makes in execution. To make the leather more workable for paring it is previously manipulated, that is to say, it is turned flesh side outwards and rolled to and fro, whilst firm pressure is applied with the second and third fingers of the right hand, thus making it pliable.

Fig. 63--Paring with French knife.

In an ordinary bindery thin or split leathers are mostly used; these do not require very much paring, which is only necessary for pig-skin and the finest moroccos. The latter leather is narrowly pared about 2 to 3 mm. wide along the edge for half as well as for whole bindings. Only the back is pared the whole width, therefore 1 to 1-1/2 cm. has to be nicely gradated. Broken places, inequalities of the edge, or even holes to be filled in, greatly add to the difficulty of the work.

In the thicker skins also--thick places often occur in the otherwise thin skins--the joint must be thinned down. The packing is laid upon the wrong side of the leather and its position marked out with the folder.

The leather is pared about 1 cm. in width along this line, that is to say, it is pared so that 1/2 cm. right and left along the mark the thickness of the leather is reduced.

As a rule, first-cla.s.s books are not provided with a cover made in advance, and even those described by publishers as "super extra" do not rise above morocco goat.

We have to do with the following leathers which are mostly used for the publishers' bindings: Goat-skin (of oriental hybrid sheep), morocco goat, sheep-skin (unsplit sheep-skin), and split sheep-skin [or so-called skivers]. There is another goat-skin, not Levanted, sold and used under the name "b.a.s.t.a.r.d" leather. "Levanting" means to imitate by pressing the grain natural to the skins from the Levant. Most kinds of our leather receive their grain by such process.

For whole-leather bindings a narrow margin is pared down all round the edges, the turn-in at the back is pared just as much as is necessary, and also at the corners. The leather corners are cut slant-wise at the outset, and the paring is done so that the thinning begins exactly at the edge of the board.

In leather bindings the board, as well as the back packing, is glued on, rubbed down, and the edges then pasted and turned in, the leather is rubbed down sharply in the joint, the back, and on the edges; but a folder must never be used on the leather covering the board itself.

It frequently happens that the board is finished off with round corners; in this case, the method of turning in cloth as well as leather is slightly different. The two neighbouring edges are turned in. The leather or other material is cut off not quite so close as for square corners, and the material is drawn very smoothly and neatly over the edges in little folds, using a pointed folder for the work.

Ill.u.s.tration: Cover corner shapes, 1

Ill.u.s.tration: Cover corner shapes, 2

Books not wholly covered with cloth or leather get corners of the same material as is used for the back. Cloth corners are not cut singly, but a strip of material long enough for the required number of corners is glued and then cut with the shears into pieces of this shape or, better, placing them on the boards in such a way that the material projects a little over the corner of the board. First of all, the lappets of the top and bottom edges are turned in, the corners nipped in the manner shown, and then the lappets of the fore-edge are also turned in. Leather corners are treated in the same way, but these are cut from waste pieces according to the zinc stencil plate kept for the purpose, and then pared down.

Ill.u.s.tration: Cover corner shapes, 3

Glue is used for fixing on cloth corners, but strong paste is always used for leather. All edges and corners are well rubbed down with the folder and left smooth and sharp, but, on the other hand, the grain on the board side must be left uninjured. Insufficient paring of the corners or using only the fingers for turning-in causes very thick edges; such work is out of date and would not be done by any thoughtful workman.

Ill.u.s.tration: Half cloth or half leather corner.

Books bound in half-cloth or half-leather have the sides covered with paper; the latter often with cloth. When cloth sides are used, the material must always harmonize with the back both in regard to colour and texture. On each side to be turned in the paper is cut 1 to 1-1/2 cm. larger than the surface of the board to be covered. The paper is cut along the back with the knife and rule. The corners are turned down in half right-angles according to the size of the cloth or leather corners and somewhat smaller than these, and cut off with the shears as shown in the ill.u.s.tration, using the fold as a guide.

Ill.u.s.tration: Small corner diagram

In ordinary work with very small corners, especially in large quant.i.ties, the corners may simply be cut off diagonally, and if there are many covers they are knocked up and the cutting is done with knife and rule or with the machine.

As a trade article for the publishers, the finished cover is lined with paper on the inside, both for the sake of improved appearance and to prevent the drawing outwards. For every board a sheet of paper is cut about 1/2 cm. smaller than the board and pasted on. The covers are placed between boards to dry.

Covers are generally decorated in some way; as a rule by means of the blocking press. Where they get any hand tooling, it is always done on the book when bound, for which no case is made in advance. Simple gold lines along the back and corners of the cover are excepted; such work is known as "filleting."

CHAPTER VII.

WORK WITH THE BLOCKING PRESS.

We make a distinction between gold tooling and blind tooling. The latter is simply an impression on the leather or other material without the use of gold, whilst the other is an impression upon a specially prepared leather or other surface, using gold leaf.

Skill in blocking depends first of all upon a tasteful and suitable selection and arrangement of the engraved blocks and letters necessary for the decoration and inscription.

The blocks, &c., are to be had ready made from the engravers in properly arranged sets; but still it is essential that the finisher should possess certain artistic taste and feeling, especially in making up the lettering. It must be borne in mind that in an inscription or t.i.tle the princ.i.p.al part (word or line) must be distinguished by larger or heavier type; furthermore, two lines of equal length must never appear in an inscription. Short words (the, and, for, &c.) worked into an inscription as separate lines add considerably to its appearance. See pp. 148 to 153 for what is said on the arrangement of the t.i.tle in hand lettering. The same applies to the arrangement of all lettering.

The blocks and letters are always fixed to the upper part of the press--the platen.

To enable alterations to be made quickly or to secure pieces which may have slipped, there is a draw-out plate made in all modern blocking presses. The engraved blocks are not affixed to this plate with glue but with cobblers' wax. The following is a practical way of managing the ornamental blocks: On a thin but very strong board about the size of the article to be blocked, the blocks are arranged with the backs uppermost, the engraved face being next to the board. This board is fixed with wax exactly in the centre of the lower part of the press--the table. By "exactly in the centre" it is to be understood that the centre of the various blocks brought together lies on or near the centre of the draw-out plate. If there are more and heavier blocks fixed to the upper than to the lower side of the plate, the latter must be lowered a little--in a word, the plate must be so adjusted that all parts receive equal pressure. It is only by making a few trials that one can learn exactly what is right.

The press should be warmed by this time, and it is well to slide in the table with the blocks adjusted upon it, and to let it remain under light pressure until plate and table are warmed throughout and no trace of moisture may be seen on either. Now put a little wax on each block, lay over them a piece of stout wrapping paper, cardboard, or similar stuff, push in and press gently; the wrapper also may be waxed. After about five minutes, open the press to see whether all parts have stuck. Until this takes place the press must remain closed. If, however, all pieces are sticking fast, draw out the table and examine the imprint of each particular part to see whether the pressure is equal; if this is not so, it remains to be seen whether such inequality is due to a faulty fixing of the plate and, if necessary, to rectify it; otherwise, pieces of paper must be made up into a suitable packing and laid upon the back of the blocks until all inequalities are removed and an even impression is obtained.

This done, the back of the set-up blocks, or the wrappers affixed thereto, is waxed at as many places as required, or rather as far as the set-up blocks extend, the plate pushed in, and the press closed until the set-up blocks adhere to the upper plate. The lighter this first impression is made, the easier it will be to detect any inequality on the table (or matrix) and to set it right by backing up with paper.

Fig. 64--Blocking press.

Before proceeding further, a few words must be said about the construction of our modern blocking presses. For modern blocking we use knee-lever presses, whilst balances are now no longer used.

On the upper part there is a sliding plate--the so-called platen--which draws out on prismatic rails.

A second plate works on hinges at the side of the sliding (or draw-out) plate and can be pulled out to the left. This plate is used princ.i.p.ally for colour blocking--the other plate for gold.

Blocking can be done in gold and colour immediately after each other, and if the plate is in duplicate, four impressions can be made in succession without having to take off and change the plate.

In the upper plate there are round borings for the gas burners or hot irons used for heating the press; the latter are out of date and do not produce a steady temperature.

It now remains to insert the article to be blocked in the press so that it will be blocked exactly on the spot required.

There are several ways of attaining this object, which are adopted according to the kind of work in hand. The surest way is to mark the place by pins.

Two large drawing pins are pasted upon pieces of cardboard, a second piece of board is placed over each one so that the head is embedded between the two pieces but leaving the points free. The gauges thus made are fixed with wax at convenient places, best on the middle line above and below the table but in such a way that they themselves are not touched by the plate. To prevent their falling off, a larger piece of cloth is pasted over them, always leaving the points visible. The surest preventive against falling off is to have screw-on gauges. A strip of metal having a slit in the middle can be screwed tightly to the table by means of a screw pa.s.sed through the slit. At the end a steel point about 1/2 cm. long is riveted on. With this gauge the points can be adjusted to any position on the table as required.