By the press system of curing, a heat far above the vulcanizing temperature may be made to do good work by a very short application. There is however danger of burning the work if left in too long. If the air-bath with thermometer or the steam vulcanizer is used, and the heat is kept down to the proper curing temperature, there is no danger of burning the india rubber even if the curing is considerably prolonged.
As the flower pot has often to be lifted off for introduction or removal of the press, and as it gets quite hot, a holder of some kind is requisite. A piece of heavy blotting paper is very convenient for this purpose.
The flower pot system with thermometer can be further simplified by being used on a stove or range. A china saucer inverted, or some similar support, should be placed under the pot. A part of the stove at very low heat will suffice. The kettle vulcanizer, can also be placed on a stove so as to dispense with gas or oil.
Finally, as the last step in simplifying the work, a stamp can be made without any special apparatus beyond a hot flat iron. The matrix may be placed on a stove where the heat is rather low, the talc-coated mixed rubber sheet placed upon it, and on this a hot flat iron. In a few minutes if the heat is sufficient the stamp will be finished.
A few words may be said about the type. High spaces and quads between the letters should be used, such as will come up to the shoulder of the type, as has been said. But a very nice effect is produced by using low quads between words. This leaves each word elevated by itself, producing a good appearance.
Autograph stamps are made from a model cut in wood by a wood engraver. The autograph is written in some form of copying ink upon a piece of paper, and is transferred by moistening and pressure to a block of wood. With an engraver’s tool the wood is cut away from the lines, as the block is routed after the inscription has been “outlined.” The woodcut is used as a model for making a matrix.
It is evident that an autograph of fair quality could be obtained from a chalk plate. But in rubber stamp work to get good results certain essential parts should be of the best. These parts include the mixed rubber, model and matrix. A departure from excellence in any of these tends to the production of an inferior stamp. What is known as a “healthy cure” is above all essential to the appearance of the product.
The stamp thus made is attached to a wooden handle by common glue or by one of the rubber cements given in chapter XVI.