TIN AND ITS ALLOYS, SOLDER, ETC Tin.—Tin is a lustrous white metal, soft, malleable, and quite ductile at the temperature of boiling water. It is very little affected even by moist air at low temperatures. It was known in very ancient times (being mentioned in the Pentateuch), and was an important article of trade with the British Islands before the Christian era. Tin is largely used in various alloys with other metals, and in melted form to coat sheet iron, tin plate, and copper.
Various compounds of tin are used in the arts. Tin dissolved in hydro chloric acid is used as a mordant in dyeing under the name of salt of tin. Another compound, called pink salt, is used as a red dye. Another, known as tin solution, brightens and fixes red colors.
Tin Plate.—This is sheet iron or sheet steel coated with tin. To coat iron or copper with tin, melt to a white heat 1 pound of malleable iron; add 5 ounces of regulus of antimony and 94 pounds of Molucca tin. Cover the melted tin with palm oil to keep out the air. Dip articles to be tinned into dilute sulphuric acid. When clean, dip in warm water to rinse, then in hot palm oil to remove the water; next in a solution of muriatic acid, copper, and zinc; finally in a tin bath, to which a small quantity of zinc has been added. When the tin ning is finished, plunge the articles into boiling water. Finally cover them with very warm sand, which sof tens the iron.
Tin plate is prepared commercially by passing through a patent pot hav ing rollers, which by their tension de termine the thickness of the coating of tin.
To Ornament Tin Plate by Moire Metallique. — Dip the plates in a strong solution of sal soda, then in water. Heat them, and sponge or sprinkle them with an acid solution, as nitric and muriatic acids, in vari ous proportions, as 1 part of sul phuric acid and 6 parts of water; I part of sulphuric acid, 2 parts of mu riatic acid, and 10 parts of water; 1 part of nitric acid, 2 parts of sul phuric acid, and 16 parts of water; rinse in water slightly acidulated with the same acids, dry, and lacquer.
To Mend Tinware.—Tin plate may be mended by covering small open ings with melted solder (an alloy of tin with lead), or by soldering a suit able patch of sheet tin, tin plate, or zinc over larger openings. Before sol
dering, it is necessary to apply a solu tion of zinc in acid to the adjacent parts. This is known as soldering liquid.
To Make Soldering Liquid.—Put in a strong glass bottle or other vessel 2 ounces of muriatic acid. Cut scraps of sheet zinc into narrow strips and feed them into the liquor as fast as they will dissolve. The acid at first will unite with the zinc and generate considerable heat, which may burst the bottle. Hence do this preferably out of doors, and take care that the acid does not get on anything of value.
Or dissolve the zinc in an open ves sel, and afterwards bottle for use.
When the acid ceases to dissolve the zinc, add 1 ounce of sal ammoniac and boil 10 minutes in an earthenware or copper vessel, but do not use any other metal for this purpose. Cork tightly. Apply this liquid with a feather to the parts to be soldered, or by wetting the cork of the bottle. A few drops are sufficient. Do not let it fall on the hands or clothing. This liquid causes the solder to flow freely and makes it adhere.
Soft Solder.—A solder suitable for the more fusible metals, as tin, pew ter, Britannia ware, and zinc, is known generally as soft solder because it has the property of melting at very low temperature. The following propor tions are recommended: For tin—common solder, I lead; I tin. Or 1 lead; I tin; 2 bismuth. This solder is soft enough to melt in boiling water.
Coarse solder, 9 lead; I tin.
Fine solder, I lead; 9 tin.
For Britannia ware, 1 lead; 1 tin; bismuth.
For zinc or lead, 1 or 2 lead; 1 tin. For pewter, 1 tin; 1 lead; 1 or 2 bismuth.
To Make and Use Solder.—Melt the metals together in any of the above proportions with gentle heat. Apply soldering liquid to the parts with a pencil or with a feather; sprinkle the parts with powdered rosin. Apply the solder and smooth with a solder ing iron. This is the usual method, but in the absence of a soldering iron a suitable solder may be made of shavings of solder melted in a large iron spoon, poured on the parts, and rubbed smooth before cooling with the bowl of the spoon.