3521. Aluminum Solder

3521.      Aluminum Solder. Depends upon the nature of the object. In order to quicken its fusion on the metal, a mixture of 3 parts balsam of copaiba and 1 part Venice turpentine is made use of; otherwise the operation is performed in exactly the same manner as in the brazing of other metals. The aluminum solder is spread without delay on the previously heated surfaces to be fastened together. In heating, the blue gas( flame or the turpentine blast lamp is employed. The more and oftener the solder is spread over the surface, the better it is.

To Solder Aluminum. The selection of either of the above solders the mixture, and pour it on an iron plate. When cold, pulverize it, and mix it with an equal weight of quicklime, sprinkle it on iron heated to redness, and replace it in the fire. It may be welded below the usual heat.

3522. Aluminum Solder

3522.    Aluminum Solder. If soft solder is fused with one-half, one-fourth, or one-eighth of its weight of zinc amalgam (to be made by dissolving zinc in mercury, see No. 3539 (To Make Zinc Amalgam for Electrical Machines)), a more or less hard and easily-fusible solder is obtained, which may be used to solder aluminum to itself or to other metals.

3523. Welding Powder for Iron and Steel

3523.    Welding Powder for Iron and Steel. For welding iron and steel a composition has lately been patented in Belgium, consisting of iron filings, 40 parts; borax, 20 parts; balsam of copaiba, or some other resinous oil, .2; and sal-ammoniac, 3 parts. They are mixed, heated, and pulverized. The process of welding is much the same as usual. The surfaces to be welded are powdered with the composition, and then brought to a cherry-red heat, at which the powder melts, when the portions to be united are taken from the fire and joined. If the pieces to be welded are too large to be both introduced at the same time into the forge, one can be first heated with the welding powder to a cherry-red heat, and the others afterwards to a white heat, after which the welding may be effected.

3524. Welding Composition for Cast Steel

3524.    Welding Composition for Cast Steel. Take borax, 10 parts; sal-ammoniac, 1 part; grind or pound them roughly together, then fuse them in a metal pot over a clear fire, taking care to continue the heat until all spume has disappeared from the surface. When the liquid appears clear, the composition is ready to be poured out to cool and concrete; afterwards, being ground to a fine powder, it is ready for use. To use this composition, the steel to be welded is first raised to a bright yellow heat, it is then dipped among the welding powder, and again placed in the fire, until it attains the same degree of heat as before; it is then ready to be placed under the hammer.

3525. Welding Powder

3525.    Welding Powder. For iron or steel, or both together, calcine and pulverize together 100 parts iron or steel filings, 10 sal-ammoniac, 6 borax, 5 balsam copaiba. One of the pieces is to be heated red, carefully cleaned of scale, the composition is to be spread upon it, and the other piece applied at a white heat and welded with the hammer.