Brick-Repressing M«chines.—Up to within a few years, the process of making orna mental bricks, tiles, etc., was carried on entirely by hand, requiring skilled labor, and 'Pro ducing but a few pieces of work per day. An example of a repressing hand-press, which will produce designs of the most complicated pattern, and manufactured by Messrs. C. W. Raymond & Co., of Dayton, Ohio, is given in Fig. ti. The dies, which are supported upon the fixed stand ard above, are made of finished brass; and as one die can easily be changed for another, the range of patterns possible is endless. The clay is first struck out by a ma chine, or molded by hand, in order to insure proper tempering and to get the requisite amount m block. After partial drying, it is put in the press, when a single stroke of the lever causes it to be molded into the desired form. As many as 2,000 blocks per hour can be made on a single press of this de scription. The large demand made by architects for ornamental brick for embellishment of the exterior of buildings has resulted in the construction of an automatic-power brick-repressing machine. which is constructed by the same mannfac tnrer, and which is illustrated in Fig. 7. llere the brick, after be ing struck out by hand or machine, and allowed properly to dry, are placed on the feeding-table by an attendant, or run indirect from the off-bearing belt. They arc then taken, by the mechanism of the press, fed into the (lie automatically, where they are subject to great and uniform pressure, which imparts to them sharp and well-defined corners and edges, after which they are discharged from the press automatically upon the endless vibra ting-belt in a finished and perfect condition. Thence they arc placed upon harrows or trucks by an off-bearer. Two men, or rather two boys, are required to operate it. The capacity of this machine is from 10,000 to 12,000 bricks per day. Not merely are brick-repressing machines adapted to the production of ornamental bricks, but it is fast becoming the practice to repress all brick used for paving purposes. It is claimed that paving bricks so repressed will not Hake or laminate, nor crack by the contact of horses' feet. They may be made of any shape, and so as to present a uniform and smooth surface, and as a roadway, while their greater density causes them to absorb less fluids and gases.
Messrs. Chambers Bro. & Co. give the following method of making pressed bricks, using their machine. To manufacture press bricks by our machine, we put on a die that will mold the bricks sufficiently narrow to drop into the mold of the press, and thick enough to make a press brick of the proper size. This can he done in five minutes. Then we use a very fine sand. largely impregnated with iron, baked dry and sieved. which is put into the sanding machine, which coats the sides and edges of the brick all over, thus making a veneering of fine iron-ore and sand on their faces. These bricks are taken from the machine in the usual manner, loaded carefully on barrows designed for the purpose with their heads all even, then their heads are rubbed with sand also (Fig. 8). Now they are wheeled to the press-shed," where they are " hacked " close; that is, so as to prevent the air from passing, between them, thereby keeping them at about the same consistency as when they were made, which is just right for repressing. From this close hack the bricks are taken and repressed in the usual manner; or, if a sufficient number of presses be used, or the machine runs slow, they may be taken and pressed direct from the barrows. This repressing brings the bricks to a mathemat ical precision as regards their size, surfaces, and angles, the flat, or largest surface of the bricks being concave, for the purpose of allowing the edges to come close, so as to show a very thin joint when laid. We do not think the skin " on the molded in our machines
usually so good as those molded in sand by hand; but where the clay gives ‘• color," and not the molding sand, then the best color is obtained by repressing our machine-bricks direct from the machine." Arrangement of Brick-Yard 31achinery.—Fig.-0 represents a ground-plan, showing the arrangement of pits, single-worker machine, boiler and engine. etc. This plan is made to show the arrangement of pits and machines, where crusher and elevator are used, or where it is found desirable to simply use the elevator. A represents the machine placed midway between the pits B and C. The pits are 19 ft. long and 20 ft. deep. The clay-crushers are placed between the two pits, and about half-way back. By this arrangement the clay is always reasonably convenient to the clay-crusher, and one pit can be filled and soaked while the other pit is being run into brick. This is by far• the best plan upon which to operate the machine. The machine does not in this case require moving, and the clay can be much more thoroughly soaked, and fed into the crusher with less labor and expense than it can be thrown into the machine. One man can feed the crusher as easily as two can feed the machine. Where a crusher is not used, an elevator, represented by D. is arranged to run over the partition between the pits. As the pits are 12 ft. wide and 20 ft. long, the shovelers are never at a great distance from the carrier, and the saving of one man's labor can be effected by this arrangement, which will pay for an elevator, or even a crusher, in a very short time. E represents the tumbling-rod which transmits the power to the machine. At P the pulleys are placed. which receive the belts from the engine J. Ii represents the boiler, and C. the crusher pulley. H represents the pulley-shaft to the crushers. These pits, boiler and engine, etc.. can all be covered by a shed, 30 X 50 ft. Where parties do not. use the elevator•, it is found desirable to make the pits, instead of 12 ft. wide and 20 ft. long, 20 ft. wide and 12 ft. long. hi this case the machine is placed in the center of each pit, and moved from one to the other. This is to facilitate getting clay to the machine, as in no case will the clay be at a greater distance than 12 ft. from the machine.
Drying Bricks.—Pig, 10 represents Chambers Bro. fi Co.'s artificial drier. This drier consists of six or more brick flues, about 43 ft. long.8i ft. wide, and 4 ft. high, built of bricks. with a railroad track through each, slightly descending from the machine, with fire-grates and doors at the lower end and a stack at the upper end. Prom the grates, upon which coal, coke, or wood is bnrned, the results of combustion are conveyed along in a flue under the bottom of the track to near the stack end, and are allowed to eseape therefrom gradually, through perforations or slots, up, under, through, and between the bricks on the iron cars. For each tunnel there are two chambers for the admission of air, one on either side of the grate com partment, which enter the conveying-1111e just back of the grate surfaee. In addition to the gases from combustion, at large amount of air is allinit Led over and at the sides of the furnaue into the flue, which becomes heated, and, when distributed through the bricks by the adjust able flue. taker up the mnisture from the bricks and carries it oft through the stack. The proportion of air to the results of combustion is regulated by swinging dampers, while the draft of the fire is under independent control by the ash-pit doors.