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Results Of These Dry Mat Experiments

( Originally Published 1927 )

Altho both Eastwood's and Schimansky's inventions were not satisfactory in a commercial sense, they certainly influenced a large number of paper makers to experiment with dry mat manufacturing and finally led to the excellent present day product.

Several German firms (Claus, Nietzsche, Benesch, Rosenthal, Geissler, etc.) took up manufacturing of dry mats as a side line in their paper mills and in due time the results of their pioneering work made the dry mat their principal product. For many years Germany was the only source of supply for dry mats, the product going to all countries in Europe and overseas.

The new dry mat process of stereotyping met with an attitude of watchful waiting on the part of the newspapers in the United States. As stated above, samples of these different European-made dry mats were tested in American newspaper offices but without arousing any enthusiasm or desire on the part of the stereotypers to adopt same in place of the well proven wet mat method.

In December, 1897, the "Inland Printer" reported on a new dry mat invention which later proved to be Schimansky's mat. It was described as a dry, spongy sheet of paper pulp with a prepared surface on one side. This mat was molded under a mangle, perfectly dry, and then without being dried in any way, placed in the casting box, and supposed to be good for eight or ten casts. In 1899, Mr. Partridge, head of the stereotype department for the A. N. Kellogg Newspaper Company of Chicago, offered to send samples of this dry mat to stereotypers who were willing to try same, provided they made reports of their tests. In September, 1899, a number of stereotypers reported on their tests and the general opinion was that the mat was not satisfactory. In the first place, it could no be run dry, as it broke and could only give a very shallow cast. Some stereotypers tried pasting tissues on this mat when facing it, and in that way got fairly good results, but ran into trouble with shrinkage, etc., and found that these so-called dry mats showed no advantage over wet mats in labor or in saving of time. In 1899, the New York Tribune experimented with these same mats, and while they were able to mold them, were not able to produce casts that they could use.

In the same year it was reported from London that a "Dry Stereotype Company" was formed which claimed to have regular customers in England, but none in London proper. They claimed to have a perfectly dry flong which was ready for the casting box immediately after being molded, without drying in any way. It was also claimed that these same mats had been used in Berlin for a year. Again a search showed that the mat in question was the Schimansky mat.

American stereotypers and paper makers began their own experimenting in the dry, cold process of stereotyping, immediately upon the arrival of the European dry mats. The "Inland Printer" reported in January, 1894, on a new cold process of stereotyping, which was offered under the name "Multotyping". The inventor, a stereotyper (the name is not given), instead of using ordinary matrix papers used asbestos paper, which he claimed could be molded in a dry state, and placed in a casting box immediately after molding. However, all asbestos papers available had very rough surfaces, so that plates cast from such mats were not very satisfactory. He therefore found it necessary to paste one or two tissues on the asbestos papers and to dry the prepared mat in a roaster. This stereotyper explained that it would no doubt be a very simple matter to find a manufacturer who made asbestos paper with a smooth face, and promised to report later on such sources of supply, but no further mention can be found of his process.

A dry mat method, which was supposed to do away with all auxiliary apparatus was invented in 1898 by JOSE W. PHOEBUS of Wheeling. Phoebus constructed a one sheet or one piece dry mat. The face surface of the mat was coated with a sizing of diluted glue by means of a high-pressure spray and when dry was not more than 1/3000th of an inch thick.

This dry mat was used in an absolutely dry state, no humidoring, no wetting, hence no steam-table, no scorcher, no drier, in short a total absence of heat or moisture at any stage of the making of the matrix. Furthermore, Phoebus' invention provided means of molding the mat, whereby the pressure upon the type was delivered evenly throughout the entire form, the pressure being direct and gradual, (similar to the action of direct pressure molding presses) thereby avoiding such injuries to the type as were caused by ordinary brush beating or by the roller processes. Phoebus describes one of the apparatuses he uses for the molding of his bone dry matrices as a form of a press in which the pressure on the mat is secured by means of a suitable fluid under pressure, such as air or water. Phoebus uses as support for the chase with the tightly locked typeform a flat table. In connection with this table he employs a stationary slab which is hollowed out at its inner side to form the fluid chamber, which lies immediately over the typeform within the chase. The edge of the fluid chamber, formed at the inner side of the slab, rests directly on the edges of the mat, which overlaps the chase. The mat forms a gasket or packing between the contracting faces of the table and the slab, thereby preventing leakage of the pressure fluid at the points of contact. The type form is placed on the table, the mat placed thereover and the hollow slab is damped to the table. The fluid is then introduced under pressure thru a fluid-supply pipe fitted to the slab, communicating with the hollow fluid chamber and when compressed air is employed for mat molding, it distributes itself throughout the fluid chamber, exerts an even pressure over the entire upper surface of the mat, causing the latter to be forced into the type faces, thereby producing the mold. When this impression has been secured a cut-off valve in the pipe is closed, the slab removed and the mat released for immediate use. The molding can also be effected by hydraulic pressure thru the pipe into the fluid chamber, but in this case a rubber sheet is placed over the mat to prevent it from becoming damp.

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