Printing and bookbinding for schools

by Samuel Jesse Vaughn

The making of wood cuts and metal plate etchings has proved one of the greatest sources of interest and educational profit to the boys and girls. It vitalizes and lends motive to design and illustration, it requires very little equipment and is a perfectly feasible scheme even for the seventh and eighth grades.

It is perhaps as well to illustrate the idea with a concrete problem. A book is being made for instance, by each pupil. He plans a cover design, a bookplate or an illustration. After the design or illustration is carefully worked out, it is traced in reverse by means of carbon paper upon a piece of wood, copper, or zinc. If it is to be a wood cut, the block is squared up to the proper thickness, about seven-eights of an inch. Birch, maple, and black walnut have proved very satisfactory for this work. Of course, in commercial work, boxwood is extensively used and the design cut on the end grain; but it is very satisfactory and much easier for the school work, to cut the figure on the side of a piece of ordinary board. With a small veining tool, such as is used in wood carving, the design is outlined, care being taken to leave the edges of the parts to be left in relief sharp and distinct. Then with a small gouge, chisel or knife, the background is cut away to the depth of about one-sixteenth of an inch. No care need be taken to make the background smooth.

Of course, the open grained woods do not give a solid, uniform impression. This is not at all objectionable as one may see by examining the wood cuts of the old masters. However, if a dense impression is desired, this experiment has been tried with good results: After the design is cut, the face of the block is gone over with a heavy coat of thick woodfiller. When the filler is dry, it is carefully scraped from the face of the design. By this simple method, a dense, clear, and uniform impression is made possible.

If it is to be a metal plate, the pupil simply takes a thick, smooth piece of copper or zinc, traces the design, and with a water color brush, he paints with asphaltum varnish the parts of the design to be left in relief. The back of the metal plate is also covered with a thin coat of the varnish. Careful examination is made to see whether air bubbles have caused small holes in the varnish, or anything else has caused any portion of the design to be left uncovered. When dry, the acid bath is prepared. Commercial nitric acid is the safest solution. It is diluted by adding about an equal volume of water to it, making it from 15% to 20% strong. The diluted acid is poured into a glass or porcelain tray and the plate put into it. If the acid can be kept moving by frequently rocking the tray, the etching will be very materially hastened. It takes from three to five hours to etch deeply a piece of copper, depending upon the strength and amount of the solution and the amount of exposed surface to be eaten away. If large surfaces are to be etched, quite a large quantity of acid is desirable, or else a changing or strengthening of the solution during the process. As soon as the acid becomes somewhat burdened with the metal, it ceases to act at all freely, and even begins to deposit a blue nitrate upon the metal. In such a case, it is best to put the plate into a fresh solution.

Fig. 29.

Care must be taken that the acid is not too strong, as the heat generated by its rapid action softens the varnish and lets the acid under to play havoc with the design. Numerous bubbles and yellow-green fumes indicate that the acid should be weakened by the addition of a small quantity of water.

By observing the progress of the etching occasionally, it can be told when the proper depth has been reached. Then the plate is heated sufficiently to soften the varnish, soaked in kerosene or turpentine, and rubbed clean with a cloth. Or the warm varnish can be removed by simply saturating the cloth with kerosene, turpentine, or benzine and rubbing over it.

A block of wood is then prepared for a base so that the mounted plate is slightly less in thickness than the height of the type. Then with a punch or a small drill, holes are put into the lower, or background, part of the metal. Through these holes the plate is fastened to the block by small tacks or escutcheon pins, the heads being sunken below the surface of the background. Large surfaces of background should be sawed out before the metal is mounted upon the block. When the cut is used in printing, it is brought up to the proper height by the underlaying of paper or cardboard.

This work is used extensively in connection with such work as cards and programs for Xmas, Thanksgiving, Easter and other special occasions. Fig. 29.