To brass small articles of iron or steel drop them into a quart of water and ½ ounce each of sulphate of copper and pro-tochloride of tin. Stir the articles in this solution until desired color is obtained.
Iron ornaments are covered with copper or brass by properly preparing the surface so as to remove all organic matter which would prevent adhesion, and then plunging them into melted brass, or copper. A thin coating is thus spread over the iron, and it admits of being polished or burnished. The better the article is finished and cleaned before dipping, the better will be the final result. R. B. Casey.
Schenectady, N. Y.
Iron or steel may be given a permanent coating of yellow brass by using a flux of boracic acid and then dipping into a pot of melted spelter, afterwards wiping off the article while still hot. The electro-plating process, however, is the best for this purpose. A coating of copper should then first be deposited on the steel, the same as if it were to be nickel-plated, and then followed with an electro-plating of yellow brass. Cleveland, Ohio. L. Miller.
To make a copper solution that will color on oily steel, take ½ ounce sulphate copper (blue vitriol), 4 ounces water, 1 table-spoonful oil of vitriol (commercial sulphuric acid) and dissolve the sulphate of copper in the water, then slowly add the oil of vitriol a few drops at a time, shaking well at each addition. Keep the mixture away from the face when adding the oil of vitriol; if the oil of vitriol is all poured in the bottle at once the stuff will boil and shatter the bottle, as I learned by experience. F. W. B.
To coat the finished surface of iron and steel with a copper film to facilitate laying out work, make a solution of sulphate of copper and apply to the work with a piece of clean waste; the copper film shows up the lines very plainly. This solution can also be used on brass by simply sprinkling iron filings on the brass surface, and then applying the copper sulphate solution. The surface to be coated should in all cases be free from oil, grease, etc.
Dayton, O. Oliver B. Voris.
Polish the iron by rubbing it well with cream of tartar, and afterward with charcoal powder, and place the metal in hydrochloric acid diluted with three times its volume of water, in which a few drops of a solution of sulphate of copper is poured. After a few minutes withdraw the iron and rub with a piece of cloth, then replace it in the solution to which add another portion of sulphate of copper. By following this plan the layer of copper may be increased at pleasure. Finally, immerse the iron in a solution of soda, wipe clean and polish with chalk. The coating thus obtained will be as firm and durable as that deposited by the electrotype process. Pittsburg, Pa. U. Peters.
A copper coating solution for use when laying out work on iron or steel which I have found more satisfactory than the ordinary blue vitriol is a mixture of saturated solution of zinc chloride with a very little copper sulphate added, say a half-dozen drops of copper sulphate to a spoonful of zinc chloride solution. When a piece of steel is rubbed with waste moistened in this solution it produces a bright copper surface that does not easily rub off.
Cleveland, Ohio. Milton Burgess.
In the process of covering cast iron with a coating of copper the pieces of cast iron are first placed in a bath made of 50 parts of hydrochloric acid, specific gravity 1.1, and one part of nitric acid; they are next immersed in a second bath comprised of 10 parts nitric acid and 10 parts chloride of copper dissolved in 80 parts of hydrochloric acid, specific gravity 1.1. The pieces are then rubbed with a woolen cloth and immersed again until the desired thickness of copper is deposited. To give a bronze appearance the copper surface is rubbed with a mixture of 4 parts sal-ammoniac and one part each of oxalic acid and acetic acid dissolved In 30 parts of water. A. L. Monrad.
New Haven, Conn.