Tinplate

“ Procure a glass plate nine inches square; cover it on both sides with tin-foil six inches square. Connect one side with the earth and the other with the machine. Charge and discharge: you obtain a brilliant spark.
In our experiment with the golden fish (Fig. 22) , we employed a common form of the Leyden-jar, only with the difference that to get to a sufficient distance from the glass, so as to avoid the attraction of the fish by the jar itself, the knob was placed higher than usual. But, with a good flint-glass tumbler, a piece of tin-foil, and a bit of wire, you can make a jar for yourself. ”

“ A tin-plate worker may even cut his base-plate out of stout block tin, and get as good results as if the bell were made by an engineer. In some makes, the base-plate is cut or stamped out of thick sheet-iron, in the form shown by the dotted lines on Fig. 18, and when thus made, the part A is turned up at right angles to form a bracket for the magnet cores, the opposite projection is cut off, and a turned brass pillar is inserted at B to hold the contact screw, or contact breaker (§ 41) . ”

“ For, if the tin foil be applied to the tip of the tongue, or to the lips, and if a piece of silver wire be made to touch the tin foil on the one side, and the spinal marrow covered by no metal on the other, contractions will be produced as often as an arc is made to the muscles by means of the moistened hand.
XVI. The object of our researches hitherto has been muscular motion; we shall now direct them to the phænomena of the senses. Let an insulated person be electrified by means of a common electrical machine, and let him apply a silver arc to the tip of his tongue covered with tin foil. ”

“ The whole is then left to itself, when crystals of tin gradually separate out on the bottom of the basin.
Properties of Pure Tin.—An ingot of pure tin is pure white (ex cept for a slight tinge of blue) ; it exhibits considerable lustre and is not subject to tarnishing on exposure to normal air. The metal is pretty soft and easily flattened out under the hammer, but almost devoid of tenacity. That it is elastic, within narrow limits, is proved by its clear ring when struck with a hard body under circumstances permitting of free vibration. ”

“ They then support each other, and yield to the hammer without tearing. These leaves are used for the silvering of glass globes, and the plating of other metals. Those that are 203used for the silvering of looking-glasses are much thicker. The article called tin-foil is an alloy, consisting generally of two parts of tin and one of lead; and capable of being beaten to less than the thousandth part of an inch in thickness.
239. LEAD is a heavy metal, of pale and livid grey colour when broken, not sonorous when pure, very flexible, and so soft that it may be marked with the nail. ”

“ They are matter transmitter and matter receiver. We have here a set of metal bars. They are made of copper, steel, aluminum, some complex alloys, and the brother to that glass cube you have before you. We will transmit this set of objects from here to there. Have you any suggestions?"
"A matter of control and identity. What have you for control?"
"Nothing that is outside of our hands," smiled Tinkin. "Would you care to send something of your own? Your gavel? Inkwell? Marked coin? Anything?"
"I'd offer my glasses except for the fact that I can not see without them," said Judge Hamilton. ”

“ Two plates of metal made very smooth, when rubbed with oil and put together, will so firmly adhere, that it will require a great force to separate them.
If two pieces of wood, or of glass, be wetted with water, and placed together, the one may be lifted up by means of the other. Boys often have a piece of leather on the end of a string, which they wet and put on a stone, and thereby lift it up.
If we take a small tube of glass with a narrow bore, and put it in water, the fluid will rise higher within the tube than in the vessel. The narrower the tube is, the higher the water rises. ”

“ Many small vessels, spoons, and other articles, are cast in an alloy somewhat harder than that which is rolled into sheets. Most of the tools employed by the Tinman are the irons, stakes, and bickers, on which the tin is hammered into proper shape, with shears for cutting, the punches for piercing holes, and the soldering iron and charcoal stove for making joints. ”

“ The embossing plate, or female die, is usually made of brass, and it contains an intaglio reproduction of the printed subject which is to be embossed. When the embossing plate is to be used on a platen press in the same way as a form of type, the plate is made type-high and is locked up in a chase with furniture and quoins in the usual manner. When the embossing plate is to be attached to a patented base, like the Hartford Electric Heater, the plate is not made type-high, but just high enough to allow for the thickness of the patented base. ”

“ First the letter itself on a small plate; then the plate placed underneath a casting form, to fix it to a small shank, which was to be cast into the form and would make, with the plate, the exact height of the letter. The letter on the plate was made not by pouring the metal into the matrix, but by beating the latter into the molten metal. When lead is heated so as to be a soft mass it easily assumes the form of any object which falls on or in it, therefore also of the matrix, which is the image of the engraved type. ”

“ Tin-plate is consumed in enormous quantities for the manufacture of the tin cans in which preserved meat, fish, fruit, biscuits, cigarettes and numerous other products are packed, and also for the household utensils of various kinds made by the tinsmitli or silversmith; terne-plates, which began to be produced in England about the middle of the 10th century. are widely employed in America for roofing purposes. ”

“ A kind of ware, called biddery ware, is made of tin alloyed with a little copper. The vessels made of this composition, are rendered black by the application of nitre, common salt, and sal ammoniac. Foil is also made by pressing it between steel rollers, [237] or by hammering it, as in the case of gold by the gold-beaters.
15. But tin is most extensively applied as a coating to other metals, stronger than itself, and more subject to oxydation. The places which are usually denominated tin, are thin sheets of iron coated with this metal. ”

“ A metal plate is so treated by help of a photographic negative that the lines of the engraving are deposited in an insoluble form upon the plate, which is otherwise clean, then a thin film of metal is deposited on all the clean places by means of electrotyping, so that when the lines are dissolved out, they are in intaglio, just as they were in the original engraved plate. ”

“ The tops of the ridges print, the valleys are the spaces which are to appear white in the impression. The second figure, a cross-section of an7 intaglio plate,—an engraving on copper we will say,—shows no hills and vales, but a flat surface with a number of V-shaped cuts filled with ink. When engraving on a copper plate, we cut with the graver into the metal every line of our design that is to appear black. Wherever we want a white space we are careful to leave untouched the polished surface of the plate. ”

“ If the tin shows any tendency to slide, use a more deeply serrated plugger. The electro-magnetic, and mechanical (engine) mallet do not seem to work tin as well as the hand mallet or hand force, as the tendency of such numerous and rapid blows is to chop up the tin and prevent the making of a solid mass, and also injure the receiving surface of the filling. In using any kind of force, always aim to carry the material to place before delivering the pressure, or blow. ”

“ This small, cast-brass plate is another example of the plates made for social or full-dress wear with the light-weight staff sword. The design on the inner ring is unusual in that the eagle, with upraised wings, is standing on the Federal shield. The plate is a bench-made product, with the inner and outer rings (p. 94) bearing the numeral VII. It was very probably a stock pattern for officers.
WAIST-BELT PLATE, C. 1836 USNM 60414-M (S-K 300) . Figure 190.
Figure 190
Rather unusual in construction, this small silver-on-copper rectangular plate was struck in thin metal. ”

“ The designing and making of the metal trimmings affords unlimited opportunity for originality, and a good plan is to fit the desired strips, cut from paper, to the box before making them of the metal. It is well to remember, [289] in this connection, that the simple bands and forms are better suited to the plain box than ornate trimmings. Having determined upon suitable patterns for the metal strips, cut them from the sheet with snips, or tinner’s shears, care being taken to produce a smooth edge. ”

“ Then it is hung over a flat cauldron filled with melted type-metal, and lowered to rest in it. When the plate has acquired the same degree of temperature as the metal, the latter is ladled and poured over the plate, filling up all the hollows and indentations, and forming a solid back of lead.257 The coating of tin is first applied, as lead will not adhere to copper.
The plate, being now ready for the planing, beveling, picking, and correcting of stereotype plates, goes through the same process that we have before described. ”

“ It has not been much improved since its invention. Steel plates may be duplicated by means of electrotyping, or by the process of transfer to soft steel, but these duplicates cannot be made so cheaply as typographic stereotype plates, nor so promptly as transfers by lithography. The inking and cleansing of the plate, always dirty and disagreeable work, has hitherto been done only by hand. All the manipulations of copper-plate work are slow and difficult: they present many obstacles to the use of labor-saving machinery. ”

“ The edges are cut by a circular saw and trimmed by machine-tools, and the plate is rendered perfectly even, and adjusted with the greatest possible exactness to the required thickness. It is prepared for the press by being screwed down upon a block of wood of a certain thickness, so that the face of the plate may have the same height as common type, the screws passing through the margin or other hollow parts of the face of the cast. No more enduring surface than the copper of these electrotype casts, backed up by the hard alloy, has yet been discovered. ”

“ In forming glass-plates by the extension of a cylinder into a plane, the workman first blows the lump of glass into the shape of an oblong pear, the length of which must be nearly equal to the length of the intended plate, and its diameter such, that the circumference when developed, will be equal to the breadth of the plate. He now rests the blowing-iron on a stool or iron bar, while an assistant with a pointed iron, pierces a hole into the extreme end of the pear, in the line of the blowing-pipe. ”

“ Transfers can be made on metal plates in much the same manner as on lithographic stones. For press work mount the plate on a piece of cardboard its own size, then, having gummed a sheet of brown paper on the face of the litho-stone, place the mounted plate near the centre and fasten it with paste or gum. This will prevent it moving about, and also raise it sufficiently from the stone to enable the printer to use his damping-cloth and roller freely. [60] Before mounting, the back of the plate should be carefully dusted to free it from grit and dirt. ”

“ The felt, carrying on its upper surface the thin sheet of pulp, passes between two rolls, usually 16 to 20 inches in diameter, the upper being made of wood and the lower one of cast iron. The pulp adheres to the upper drum and the felt passes round the lower drum back to the box containing the mixture of pulp and water; the thin sheet is continuously wound on the upper roll until a certain thickness is reached. ”

“ A prepared daguerréotype plate is enclosed in a box full of water having a glass front with a shutter over it; between this glass and the plate is a gridiron of silver wire; the plate is connected with one extremity of a galvanometer coil, and the gridiron of wire with one extremity of a Breguet's helix; the other extremities of the galvanometer and helix are connected by a wire, and the needles brought to zero. As soon as a beam of either daylight or the oxy-hydrogen light is, by raising the shutter, permitted to impinge upon the plate, the needles are deflected. ”

“ A superior kind of tin ware, commonly known as block tin ware, is carefully finished by beating or planishing with a polished steel hammer upon a metal stake. The process of swaging is resorted to as a ready means of producing grooved or ridged borders, or other embossed ornaments. This process consists in striking the metal between two steel dies or swages, the faces of which bear the desired pattern, and are made counterparts of each other. ”

“ The world’s consumption of tin-plate has risen to enormous proportions, the extraordinary expansion of the tinned or canned food industry being responsible for this development. Thousands of tons of steel are absorbed in the manufacture of these containers, as well as hundreds of tons of tin and solder. Upon the removal of the contents the tins are generally thrown away, especially by the prodigal nations. ”

“ Last of all the sheet is bedded, as we call it, and each side is polished with rouge, or red oxide, between moving pads of felt."
"Goodness!" ejaculated Jean. "Do you mean to say they have to go through all that with every sheet of plate glass?"
"Every sheet of polished plate," corrected Giusippe. "Rough plate does not need to be polished or ground down much. It is made merely for use and not for beauty. Sometimes to add strength, and help support the weight of large sheets, wire netting is embedded in them. ”

“ COPPER-PLATE PRINTING.
Copper, or Steel-plate Engravings, are Printed by a different process. The Copper, or Steel-plate Press, is formed of two Rollers, one placed over the other, with only a sufficient space between to allow a board to pass, when a strong force is applied. The Plate is then laid on a small fire adapted to the purpose, so as to heat it sufficiently to liquify the Ink, and cause it to diffuse itself over every part of the Engraving. ”