Chapter I: II III IV

Tin 1 3 1 2 Lead 1 5 1.5 2 Bismuth 2 8 3 5 Antimony — — — 1

«TIN ALLOYS:»

«Alloys for Dentists’ Molds and Dies.»—I.—Very hard. Tin, 16 parts; antimony, 1 part; zinc, 1 part.

II.—Softer than the former. Tin, 8 parts; zinc, 1 part; antimony, 1 part.

III.—Very hard. Tin, 12 parts; antimony, 2 parts; copper, 1 part.

«Cadmium Alloy, about the Hardness of Zinc.»—Tin, 10 parts; antimony, 1 part; cadmium, 1 part.

«Tin-Lead.»—Tin is one of those metals which is not at all susceptible to the action of acids, while lead, on the other hand, is very easily attacked by them. In such alloys, consequently, used for cooking utensils, the amount of lead must be limited, and should properly not exceed 10 or 15 per cent; but cases have been known in which the so-called tin contained a third part, by weight, of lead.

Alloys containing from 10 to 15 per cent of lead have a beautiful white color, are considerably harder than pure tin, and much cheaper. Many alloys of tin and lead are very lustrous, and are used for stage 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.
0 7.290
1 7.316
2 7.342
3 7.369
4 7.396
5 7.423
6 7.450
7 7.477
8 7.505
9 7.533
10 7.562
11 7.590
12 7.619
13 7.648
14 7.677
15 7.706
16 7.735
17 7.764
18 7.794
19 7.824
20 7.854
21 7.885
22 7.916
23 7.947
24 7.978
25 8.009
26 8.041
27 8.073
28 8.105
29 8.137
30 8.169
31 8.202
32 8.235
33 8.268
34 8.302
35 8.336
36 8.379
37 8.405
38 8.440
39 8.476
40 8.512
41 8.548
42 8.584
43 8.621
44 8.658
45 8.695
46 8.732
47 8.770
48 8.808
49 8.846
50 8.884
60 9.299
70 9.736
80 10.225
90 10.767
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 Tin Alloys.»—I.—Alger Metal.—Tin, 90 parts; antimony, 10 parts. This alloy is suitable as a protector.

II. Argentine Metal.—Tin, 85.5 per cent; antimony, 14.5 per cent.

III.—Ashberry metal is composed of 78 to 82 parts of tin, 16 to 20 of antimony, 2 to 3 of copper.

IV. Quen’s Metal.—Tin, 9 parts; lead, 1 part; antimony, 1 part; bismuth, 1 part.

«Type Metal.»—An alloy which is to serve for type metal must be readily cast, fill out the molds sharply, and be as hard as possible. It is difficult to satisfy all these requirements, but an alloy of antimony and lead answers the purpose best. At the present day there are a great many formulas for type metal in which other metals besides lead and antimony are used, either to make the alloy more readily fusible, as in the case of additions of bismuth, or to give it greater power of resistance, the latter being of especial importance for types that are subjected to constant use. Copper and iron have been recommended for this purpose, but the fusibility of the alloys is greatly impaired by these, and the manufacture of the types is consequently more difficult than with an alloy of lead and antimony alone. In the following table some alloys suitable for casting type are given:

Lead Antimony Copper Bismuth Zinc Tin Nickel
I 3 1 — — — — —
II 5 1 — — — — —
III 10 1 — — — — —
IV 10 2 — 1 — — —
V 70 18 2 — — 10 —
VI 60 20 — — — 20 —
VII 55 25 — — — 20 —
VIII 55 30 — — — 15 —
IX 100 30 8 2 — 20 8
X 6 — 4 — 90 — —

The French and English types contain a certain amount of tin, as shown by the following analyses:

English Types French Types I II III Lead 69.2 61.3 55.0 55 Antimony 19.5 18.8 22.7 30 Tin 9.1 20.2 22.1 15 Copper 1.7 — — —

Ledebur gives the composition of type metal as follows: