Henley's Twentieth Century Formulas, Recipes and Processes. Various

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СКАЧАТЬ jewelry and mirrors for reflecting the light of lamps, etc. An especially brilliant alloy is called “Fahlun brilliants.” It is used for stage jewelry, and consists of 29 parts of tin and 19 of lead. It is poured into molds faceted in the same way as diamonds, and when seen by artificial light, the effect is that of diamonds. Other alloys of tin and lead are employed in the manufacture of toys. These must fill the molds well, and must also be cheap, and therefore as much as 50 per cent of lead is used. Toys can also be made from type metal, which is even cheaper than the alloys of tin and lead, but has the disadvantage of readily breaking if the articles are sharply bent. The alloys of tin and lead give very good castings, if sharp iron or brass molds are used.

Lead	19 parts
Tin	29 parts

      This alloy is very bright and possesses a permanent sheen. It is well adapted for the making of artificial gems for stage use. It is customary in carrying out the process to start with two parts of tin and one part of lead. Tin is added until a sample drop which is allowed to fall upon an iron plate forms a mirror. The artificial gems are produced by {78} dipping into the molten alloy pieces of glass cut to the proper shape. The tin coating of metal which adheres to the glass cools rapidly and adheres tenaciously. Outwardly these artificial gems appear rough and gray, but inwardly they are highly reflective and quite deceptive when seen in artificial light.

      If the reflective surfaces be coated with red, blue, or green aniline, various colored effects can be obtained. Instead of fragile glass the gems may be produced by means of well-polished pieces of steel or bronze.

      Other Tin-lead Alloys.

      —Percentage of lead and specific gravity.

P. C.	S. G.	P. C.	S. G.
0	7.290	28	8.105
1	7.316	29	8.137
2	7.342	30	8.169
3	7.369	31	8.202
4	7.396	32	8.235
5	7.423	33	8.268
6	7.450	34	8.302
7	7.477	35	8.336
8	7.505	36	8.379
9	7.533	37	8.405
10	7.562	38	8.440
11	7.590	39	8.476
12	7.619	40	8.512
13	7.648	41	8.548
14	7.677	42	8.584
15	7.706	43	8.621
16	7.735	44	8.658
17	7.764	45	8.695
18	7.794	46	8.732
19	7.824	47	8.770
20	7.854	48	8.808
21	7.885	49	8.846
22	7.916	50	8.884
23	7.947	60	9.299
24	7.978	70	9.736
25	8.009	80	10.225
26	8.041	90	10.767
27	8.073	100	11.370

      Tin Statuettes, Buttons, Etc.—

I.—	Tin	4 parts
Lead	3 parts

      This is a very soft solder which sharply reproduces all details.

      Another easily fusible alloy but somewhat harder, is the following:

II.—	Tin.	8 parts
Lead	6 parts
Antimony	0.5 part

      Miscellaneous СКАЧАТЬ