The Rapid Electrotype Company developed and built these casting-machines in its own machine shop and owns the patents covering them.
THE ALUMINOTYPE PROCESS
The development, perfection and introduction of the Aluminotype Process for duplicating a printing surface in a solid piece is one of the outstanding accomplishments of The Rapid Electrotype Company, and marks a distinct step in advance of the other and older methods used in the graphic arts, for certain classes of printing.
Aluminotypes are much harder than an electrotype or stereotype and have as sharp and deep a printing face as an electrotype. The Aluminotype process will reproduce as sharp and clear as the electrotyping process an eighty line screen half-tone, which is really too fine a screen for newspaper printing.
A distinct advantage Aluminotypes have is in the item of weight. An Aluminotype, unmounted, weighs only one quarter as much as an unmounted electrotype or stereotype of the same size. When mounted on a wood base an Aluminotype weighs just one half as much as an electrotype or stereotype of the same size mounted on wood. In a national advertising campaign where a general list of newspapers is used Aluminotypes, by reason of their light weight, effect a marked saving in parcel-post or express charges. This saving in postage is especially noticeable in the case of foreign country newspaper campaigns.
In addition, because of their toughness, a saving can be made in packing Aluminotypes, inasmuch as they do not require the expensive precautions in packing to avoid injury in transportation that electrotypes or stereotypes do. They will not bend; their printing face cannot be injured by the ordinary mishaps attendant upon handling in transportation. For all practical purposes it can be said that Aluminotypes are indestructible.
MATRICES
The ordinary practice followed in making mats is to use an electrotype or stereotype pattern plate made from the original form. Sometimes the original itself is used.
The first mat molded from an electrotype pattern plate will be sharp. The next one molded will be a little less sharp than the first. The third one molded will be slightly less sharp than the second one. In other words, with every succeeding mold, the electrotype or stereotype pattern plate is mashed a little by the pressure of the matrix press until it has to be discarded and a new one used.
The five-thousandth mat made by the Rapid Electrotype Company from the same pattern plate is as sharp as the first one molded. This is because an aluminotype pattern is used from which to mold. Aluminotypes will not mash under the pressure of the matrix press, as they are much harder than electrotypes.