A soft soldering fluid that will not rust tools is found in oleic acid (crude).
(2) For soldering fluid take one drachm each of powdered copperas, borax, and prussiate of potash; 1/2 ounce of powdered sal-ammoniac; 3 1/2 ounces fluid muriatic acid; let the mixture cut all the zinc it will and then dilute with 1 pint of water.
(3) For soldering fluid: Add granulated zinc or zinc scraps to two fluid ounces of muriatic acid until hydrogen ceases to be given off; add one teaspoonful of ammonium chloride; shake well and add 2 fluid ounces of water.
To solder gray cast-iron, first dip the castings in alcohol, after which sprinkle muriate of ammonia over the surface to be soldered. Then hold the castings over a charcoal fire till the sal-ammoniac begins to smoke; then dip it into melted tin. This prepares the castings for soldering, which is done in the usual way.
Some of the common soldering for gold is composed of the following ingredients:
1 part Copper, 9 parts Gold,
2 parts Silver.
(This solder is to be used for gold of fineness 750 for hard soldering.)
3 parts Copper, 7 parts Silver. 12 parts Gold.
(This solder is to be used for soft soldering for gold of fineness 750).
(1) 1 part Copper, 2 parts Copper, 3 parts Gold.
(2) 5-10 parts Copper, 5-10 parts Silver, 2 parts Gold.
(These solders are to be used for gold of fineness 583).
(1) 1 part Copper, 2 parts Silver, 1 part Gold.
(2) 2 parts Silver, 1 part Gold.
(3) 2 parts Copper, 1 part Gold.
(These solders are for gold for less fineness than 583). A solder for gold that is readily fusible consists of 5 1-100 parts Zinc, 54 74-100 parts Silver, 28 17-100 parts Copper, 11 94-100 parts Gold.
A soldering liquid is prepared by the dissolution of small pieces of zinc in pure hydro-chloric acid until effervescence stops. After a wait of a day or two the undissolved zinc is to be taken out and the solution filtered, compounded with 1-3 its volume of spirits of sal-ammoniac, and then diluted with rain water. If this soldering liquid be used there is no rust caused on iron or steel.
(2) Another soldering liquid is made by the dissolution of 1 part glycerine and 1 part of lactic acid in 8 parts of water.
A soldering paste is made by a mixture of chloride of tin with starch paste.
To solder Russia iron, heat the piece of iron with a well-heated soldering iron for about half an inch. It don't want to be made too hot, but draw the iron over same, say for 8 or 10 inches, and then, while it is hot apply raw muriatic acid, rubbing the soldering over same; then with a wet cloth wipe clean and apply cut acid and solder, rubbing the hot iron over same and while hot wipe off with the wet cloth, and it should be as bright as tin and as easy to solder.
To solder saws the tools required are a blow-pipe, a piece of charcoal, some borax and spelter. The ends of the saw are filed smooth, so that one side will lap over the other and the sides opposite each other are to be fitted together and the bundle bound with iron and wire for keeping it in place. The lap is then dampened with borax which has been dissolved in water, and the saw is placed on the charcoal. The broken parts are to be put near the gas-jet and the parts previously wet with the spelter are to be sprinkled and the flame of the gas is to be blown until the spelter runs. It should be cold before it is removed. When quite cold it should be filed quite flat with the other part of the saw.