Trans′fer-lathe.
（Coining.) For the purpose of reducing large designs in relief, to proportions suitable for coin, a machine has been invented in France and imported into the United States Mint. If the design has been made in wax or other soft material, a cast in metal is taken of it, and from this copy, properly fixed in the transferring-machine, the engraving is made on the end of the hub from which dies are to be sunk. The brass cast is fastened to the larger wheel of the machine, and the softened steel plug to the small wheel on an arbor parallel to the former. These wheels revolve at an equal rate. Across the front of the machine, opposite the faces of the cast and the steel block, is a horizontal bar, pivoted at one end to a standard on the bed-piece, and drawn toward the faces of the cast and block by a spring. On this lever are two important parts of the machine. A steel stub projects against the face of the copy and a graver against the face of the steel block. Now, as the two wheels revolve, the cameo or salient design on the copy thrusts out the stub, and the graver is withdrawn in the equivalent ratio from the steel. When the steel stub traverses the flat face of the copy, the graver does the same on the steel. The relative distance of the stub and the graver from the pivotal point of the lever-bar, to which they are both attached, determines the proportion which the engraving shall bear to the cast. The wheels having made a revolution, and a circular chip having been taken from the steel, the outer end of the lever is dropped a little, so as to bring the stub and graver to other places, where the operation is repeated, another chip being taken. The operation thus proceeds till the whole face of the casting and steel have been traversed, the latter being a “copy in little” of the former. The roughnesses and graver-marks are dressed off by the tools of the diesinker.
