The linoleum which is intended for printing must first have its edges trimmed. This is done upon long tables, the sides of which must be perfectly true. A straight-edge runs along the side of the table, and carries a knife-blade, which cuts off the irregular margin of the cloth. The cuttings produced in this way, as well as all other scraps of linoleum, are separated from the canvas by hand, and are used, with an additional quantity of cement, for making stair-cloth. For printing 'by machine, several lengths of linoleum are joined by narrow strips of calico, covered with glue. and applied with the aid of a hot iron.
Hand Printing.—The blocks for printing flooreloth are made of at least three layers of well seasoned pine, glued together so that the grain of the wood in one layer runs at right angles to that in the adjoining one. The total thickness of each block is 2-24 in. according to width, it being essential that the block should be perfectly rigid, while it must not be too heavy for the printer to lift with one hand. The face is made of sycamore or pear-wood, preferably the latter. For each colour in the pattern, a separate block is required, and, in addition, there is usually an outline block and a "smash "-black. The latter covers every colour except the outline, its object being to distribute the paint uniformly. When any pattern contains a huge surface of colour, the smash block is indispensable, as without it the paint will remain rained in the centre of each field, owing to the suction produced by raising the block. The smash-block is prevented from clogging, by beating it upon a clean pad, so eoou as the paint begins to choke up the open spaces. The outline block is applied immediately after the smash-block ; it gives a finish to each field of paint, the surface of the block is still made of wood ; for finer work, metal is indispensable. The " dot " patterns for oilcloth are produced in a very simple manner. The pear-wood or boxwood face of the block is divided into small squares, by means of parallel saw-cuts, crossing each other at right angles, and penetrating to a depth of about I in. The pattern is transferred to the surface of the block thus prepared, and those squares not included in it are cut away. It need hardly be remarked that patterns printed with such blocks present a dotted appearance, and, for this reason, they are only suited for oilcloth where the whole of the surface is covered with paint, and are not adapted for linoleum, where part of the surface remains plain.
For the commoner kinds of linoleum, and similar fabrics, the blocks used are made as follows : The outline of the pattern is transferred to the pear-wood face of the blocks, and those parts of the wood which are not required for taking up the paint are removed by means of cutting instru ments of various shapes. If the raised portions remaining be of considerable area, they are grooved, in order to distribute the paint more evenly. Such grooved wooden blocks possess, however, but little durability, and are in such constant need of repair that, where a large quantity of goods of one pattern have to be printed, it is more advantageous to construct the face of metal. The metal used is brass, about in. wide, of a wedge-shaped section, and of different thicknesses according to the work for which it is intended, The pattern having been drawn upon the pear wood face of the blocks, those parts which are to receive the paint are furnished with parallel lines, similar to the shading in a wood-cut, but on a much larger scale. Incisions are made along these lines with the help of small, thin, chisels, and the metal, having been cut into pieces of a suitable length, is driven in. The pieces are first perforated at short intervals with 1-in. holes, to afford , passage for the air in raising the blocks, and thus prevent inequalities in the paint due to suction. In hammering in the metal, a small block of steel, whose thickness equals the height of metal required, is placed upon the wood. The hammer is stopped by the steel as soon as the brass is driven in far enough, and uniformity in height is secured. The distance apart of the parallel lines is regulated by the thickness of the metal to be used, and this again by the area of the printing surface on the block. For curved lines, the metal is bent by hammering it with steel punches of various curves upon a block of lead. When the whole block has been metalled, the face is ground down upon a flat sandstone and smoothed with lump pumice. When a block is heavily metalled, it is sometimes necessary to drive small nails into the pear-wood face, to prevent it from yielding under the lateral pressure caused by the insertion of so many metal wedges.