[Footnote 1: Zinc chloride is the ordinary “killed spirits.”]
Solder wire is very handy for small work, and can be made in the following way: Roll a sheet of stiff writing or drawing paper into a conical form, rather broad in comparison with its length; make a ring of stiff wire to hold it in, attaching a suitable handle to the ring. The point of the cone should first of all be cut off to leave an orifice of the size required. It should then be filled with molten solder, and held above a pail of cold water, and the stream of solder flowing from the cone will solidify as it runs and form the wire. If held a little higher, so that the stream of solder breaks into drops before striking the water, it will form handy elongated “tears” of metal; when it is held still higher, each drop forms a thin concave cup or shell, and each of these forms will be found to have its own peculiar uses in blowpipe work.
The method adopted for granulating tinman’s solder, which is very rarely called for, is as follows: Place a piece of wood, well greased, over a tub containing water, and by gently pouring the molten alloy from a distance in a small stream on to the greased board, the metal is broken up into a large number of very fine shots, which run off the board into the water and are immediately cooled. The fine shots are then taken from the water and gently dried.
=Making Solder from Pewter.=--This alloy is composed of variable proportions of tin and lead, the average composition being about 4 parts of lead to 1 part of tin. If old pewter is to be utilised for making solder, tin will have to be added to the molten pewter. Thus, to convert 5 lb. of average pewter to “coarse” or “common” solder, add 1 lb. of tin; to “fine” or “medium,” add 3 lb. of tin; and to “very fine” or “best,” add 7 lb. of tin. The respective proportions of lead and tin will then be 2 and 1; 1 and 1; and 1 and 2. After the proper quantity of tin has been added, mix some powdered sal-ammoniac with the molten metals, and well stir the alloy; it is then ready for pouring into the moulds.
=Making Coarse Solder from Composition Piping.=--Good composition piping is made of nearly all tin, or an alloy of tin and lead, in which the former metal is in excess, and formerly was much used by plumbers in the making of coarse solder, as the material consisted of odd pieces of small value. As, however, a great deal of composition tubing is made out of old metals of which lead, tin, antimony, arsenic, and zinc form the alloy, it is not advisable to introduce it into solder. Should it be done, the melting point of the solder would be raised, and in applying it to the lead to be joined together, would probably partly melt it. Neither do the metals named alloy in a thorough manner, but partake more of the nature of a mixture in which the constituents partly separate when making the joints, and some, especially zinc, show as small bright lumps on the surface. Joints wiped with what is usually called “poisoned metal” are difficult to make, almost invariably leak when on water service pipes, and are dirty grey, instead of bright and clean. The zinc could be removed from the mixture by the method already given.