Table 74.-MIXTURES OF METAL FOR BRONZE, GUN METAL, BRASS. AND OTHER CASTINGS. NUMBER OF PARTS OF Description of Work the Alloy is suitable for. Copper. Tin. Zinc. Lead. Hard bronze . Metal for piston rings, requires no lubrication. Good locomotive brass boiler tubes; I fine spelter Gun metal for locomotive engine bearings, and for valves and glands 84 Gun metal for railway carriage and wagon bearings Gun metal for general castings for best work. Metal for glands, spindles, and eccentric straps. Gun metal for railway carriage, engine, and machinery bearings Metal for slide valves Metal for pumps and other hydraulic purposes Metal for covering iron rods, such as pump rods, &c. Metal for cocks, valves, and taps for water Metal for embossing press Metal for rolls Hard metal for bearings 85 93 brass Hard gun metal 16 1212 ... :: Good brass for railway carriage and for engine and machinery bearings Good brass for all ordinary castings for engines and machinery Good brass for pump buckets, plungers, valves, Metal for axle boxes of carriages and carts Metal for ornamental brass castings Table 74 continued.-MIXTURES OF METAL FOR BRONZE, GUN METAL BRASS, AND OTHER CASTINGS. Description of Work the Alloy is suitable for. NUMBER OF PARTS OF Copper flanges for pipes Anti-corrosive metal to stand acids 7 antimony Metal for bearings exposed to heat 37 spelter 62 ... 18 I 8 I ... ... 3 7 2 I I 81 Sheet brass White brass Red brass Brass wire. Bristol sheet brass; solders well Brass for mathematical instruments Brass for watch-makers, malleable Button-maker's brass 48 4 II I 80 19 ... 5 25 2 ... ... 33 10 brass 83 161 83 Metal for punches for jewellery and instruments Metal for screw propellers Gilding metal Lap alloy Metal for brass rivets Metal for copper rivets Dipping brass, another Mosaic gold metal. 6 spelter 19 ... 7 I ... I 3 5 1 Table 74 continued.—MIXTURES OF METAL FOR BRONZE, GUN METAL, BRASS, AND OTHER CASTINGS. bell, in inches 6 7 8 10 12 14 16 20 25 30 35 40 45 50 60 70 80 911 Weight, in lbs. 46 11162245 68 197 393 645 900 1345 1795 2580 2920 7952 11256 18228 Thickness of Bells.-To obtain variety of tone, the thickness of house bells should range from th toth of their diameter. Clock bells and dinner bells should be not less thanth of their diameter in thickness. Large church bells and peals of bells range from th toth the diameter in thickness at the sound bow. The clapper of small bells should be about, and for large church bells from to the weight of bell. The largest bells in England are:-Great Paul, of St. Paul's Cathedral, which is composed of 13 lbs. of copper to 4 lbs. of tin, and weighs 37,383 lbs.; Great bell of Westminster, weighs 30,352 lbs.; Manchester, 18,256 lbs.; Tom of Oxford, 17,360 lbs. ; Tom of Exeter, 13,440 lbs.; Tom of Lincoln, 12,096 lbs.; and Tom of St. Paul's, weighs 11,474 lbs. WHITE METAL. White Metal being one of the best alloys for reducing friction, is commonly called antifriction metal. It is cheaper than gun-metal, but it is much softer and is liable to crush and spread out, unless cased in an iron box. Babbit's original receipt was: 4 lbs. copper; 8 lbs. antimony; 24 lbs. tin = 36 lbs. This was called hardening. For every lb. of the above he added 2 lbs. more tin, making altogether 108 lbs. A great number of other mixtures are now used by brassfounders, and a collection of those most generally used is given in the following table, containing 72 different alloys. Table 76.-ANTIFRICTION WHITE METAL AND OTHER ALLOYS. NUMBER OF PARTS OF Description of Work the Alloy is suitable for. Tin. Copper. Antimony. Lead. White metal for filling perforations in slide valves Antifriction white metal for bearings of engines, millwork, machine tools, and general machinery 90 +2560 94510 10 10 ∞∞ 8 8 ΙΟ ΙΟ 12 ... ... 6 Antifriction white metal for bearings of engines, shafting, tools, millwork, and machinery Antifriction white metal, used for lining locomotive axle boxes, and bearings of machine tools. Antifriction white metal for bearings of shafting, implements, &c., and general machinery . TABLE 76 continued.-ANTIFRICTION WHITE METAL AND OTHER ALLOYS. NUMBER OF PARTS OF Description of Work the Alloy is suitable for. Tin. Copper. Antimony. Lead. Antifriction white metal for light machinery bearings Hard white metal Hard white metal, another White metal for sockets German silver for castings 20 brass; 3 spelter I brass Imitation silver, another Imitation silver Pewter Metal for organ pipes Pewter, common Pewter, fine I zinc ... 4 2 I ... Nickel alloy in sheets Nickel alloy for models, &c. Electric amalgam Electrum Queen's metal Metal for ornaments and lamps 50 ... 1 zinc; 1 nickel White metal for buckles and buttons 16 brass; 2 zinc 4 mercury; 2 zinc 71⁄2 zinc; 8 nickel Britannia metal Type metal Stereotype metal 2 bismuth ... I bismuth I Imitation platinum Tutenag Metal for medals 2 : Alloy for fusible plugs,softens at 366°,melts at 372°F. |