METAL SPRAYING

Te Aroha News, Volume XLI, Issue 6546, 20 November 1924, Page 3

METAL SPRAYING

A WONDERFUL PROCESS RUSTLESS IRON COAT FOR WOOD - preat interest was, attracted by a detailed description of the methods . a,ijid advances made in metal spraying by Mr T. H. Turner and Mr W. E. Ballad at the Institute of Metals (states t£e “Morning Post”). Although tliis - .process has been known for the past years, its development was retarded by the war, and it is now only just opening out, and the full possibilities have not yet been realised. |jriefly, it consists of treating metals of, practically every description as if , -they were scent in a scent spray,and

depositing them on any desired object in the form of a fine adherent dust. The metal surface thus obtained be burnished or polished ta any degree, and is permanent. tiij The spray is produced and projected an instrument resembling a large automatic pistol, but the magazine is loaded with a reel of wire in place of cartridges, and the propulsive charge of oxygen, hydrogen, and compressed airi As the wire reaches the muzzle it is converted into a cloud of tiny metallic particles, which, travelling at very high speed, become hiolteh on striking the targets, and form a solid coating. In spite of the great heat of the oxy-hydrogen flames !»used in vaporising the metal, the jmost delicate, as well as the most ro,bust, materials are undamaged by the process, and of this many interesting examples were shown. •' v DESIGNS ON SILK Designs produced by spraying silk and cotton fabrics with brass and copper alloys were shown, the method being to place a paper stencil over the material and direct the pistol at it. Fabrics are not affected by washing. Even thin paper is not scorched, and the palm of the hand can be plated with pure metal without discomfort, and glass can also be coated in the same manner. , The industrial applications are many and are now being used in six European countries as well as America. A coating of any thickness of non-corrosive metal can be applied to any structure, thus preserving it from the action of weather or chemical fumes—a matter of great importance in shipbuilding and engineering in general. It is possible to spray a nonporpps s coat of tin, lead, or zinc on any object, and also to preserve wood by spraying it with rustless iron. EXPERIMENT WITH PLATINUM A feature of the process that will be watched with interest by chemists is the experiment of coating porcelain and silica with platinum. The high cost of this rare metal has hampered many research workers in chemistry, for it is absolutely essential for certain operations, and the present cost of even a tiny platinum crucible is beyond the means of the average private experimenter. Should the result prove satisfactory, and Mr Turner told a representative .. of the “Morning Post” that there was every hope that it would, the scope- of research of the smallest research worker will be greatly increased. Solid bars that can be filed and machined can also be produced by the process. Many, samples were shown, including bells made from copper and zinc, giving a characteristic ring which has hitherto been regarded as impossible in the case of metal objects built up in this way.