III.—Brass 7 parts
Zinc 1 part
IV.—Zinc 49 parts
Copper 44 parts
Tin 4 parts
Lead 2 parts
Prechtl’s Composition.—
V.—Copper 53.3 parts
Zinc 43.1 parts
Tin 1.3 parts
Lead 0.3 parts
All these hard-solder compositions have the fine yellow color of brass,
are very hard, and can be fused only at high temperatures. They are
well adapted for all kinds of iron, steel, copper, and bronze.
Solders which fuse at somewhat lower temperatures and, therefore, well
adapted for the working of brass, are the following:
VI.—Sheet brass 81.12 parts
Zinc 18.88 parts
VII.—Copper 54.08 parts
Zinc 45.29 parts
VIII.—Brass 3 to 4 parts
Zinc 1 part
A solder which is valuable because it can be wrought with the hammer,
rolled out, or drawn into wire, and because it is tough and ductile, is
the following:
IX.—Brass 78.26 parts
Zinc 17.41 parts
Silver 4.33 parts
Fusible White Solder.—
X.—Copper 57.4 parts
Zinc 28 parts
Tin 14.6 parts
Easily Fusible Solders.—
XI.—Brass 5 parts
Zinc 2.5 parts
XII.—Brass 5 parts
Zinc 5 parts
Semi-White Hard Solders.—
XIII.—Copper 53.3 parts
Zinc 46.7 parts
XIV.—Brass 12 parts
Zinc 4 to 7 parts
Tin 1 part
XV.—Brass 22 parts
Zinc 10 parts
Tin 1 part
XVI.—Copper 44 parts
Zinc 49 parts
Tin 3.20 parts
Lead 1.20 parts
Formulas XIII and XVI are fairly fusible.
White Hard Solders.—
XVII.—Brass 20 parts
Zinc 1 part
Tin 4 parts
XVIII.—Copper 58 parts
Zinc 17 parts
Tin 15 parts
XIX.—Brass 11 parts
Zinc 1 part
Tin 2 parts {659}
XX.—Brass 6 parts
Zinc 4 parts
Tin 10 parts
XXI.—Copper 57.44 parts
Zinc 27.98 parts
Tin 14.58 parts
For Brass Tubes.—I.—Copper, 100 parts; lead, 25 parts.
II.—A very strong solder for soldering brass tubes to be drawn, etc.,
is composed of 18 parts brass, 4 parts zinc, and 1 part fine silver.
For Fastening Brass to Tin.—To 20 parts of fine, reduced copper, add
sufficient sulphuric acid to make a stiff paste. To this add 70 parts
of metallic mercury, and work in, at the same time applying heat until
the mass assumes a wax-like consistency. Warm or heat the plates to be
united, to about the same temperature, apply the mixture, hot, to each,
then press together, and let cool.
«COPPER SOLDERS.»
The copper solders which are used for soldering copper as well as
bronze are mixtures of copper and lead. By increasing the quantity of
lead the fusibility is increased, but the mixture departs from the
color and toughness of copper. The most commonly employed copper solder
is the following:
I.—Copper 5 parts
Lead 1 part
II.—Copper 80 parts
Lead 15 parts
Tin 5 parts
For Red Copper.—I.—Copper, 3 parts; zinc, 1 part.
II.—Copper, 7 parts; zinc, 3 parts; tin, 2 parts.
«FATS FOR SOLDERING.»
I.—Soldering fat or grease is commonly a mixture of rosin and
tallow with the addition of a small quantity of sal ammoniac. It is
particularly adapted to the soldering of tinned ware, because it is
easily wiped off the surface after the joint is made, whereas if rosin
were used alone, the scraping away might remove some of the tin and
spoil the object.
II.—The following is a well-tried recipe for a soldering grease: In a
pot of sufficient size and over a slow fire melt together 500 parts of
olive oil and 400 parts of tallow; then stir in slowly 250 parts of
rosin in powder, and let the whole boil up once. Now let it cool down,
and add 125 parts of saturated solution of sal ammoniac, stirring the
while. When cold, this preparation will be ready for use.
«FLUIDS FOR SOLDERING.»
I.—To the ordinary zinc chloride, prepared by digesting chips of
zinc in strong hydrochloric acid to saturation, add 1/3 spirits of
sal ammoniac and 1/3 part rain water, and filter the mixture. This
soldering liquid is especially adapted to the soft soldering of iron
and steel, because it does not make rust spots.
To solder zinc, the zinc chloride may be used without any spirit sal
ammoniac.
II.—Mix phosphoric acid with strong spirits of wine in the following
proportions:
Phosphoric acid solution 1 quart
Spirits of wine (80 per cent) 1 1/2 quarts
More or less of the spirits of wine is used depending upon the
concentration of the phosphoric acid solution. When this soldering
liquid is applied to the metal to be soldered, the phosphoric acid
immediately dissolves the oxide. The hot soldering iron vaporizes the
spirits of wine very quickly and causes the oxide released by the
phosphoric acid to form a glazed mass with the surplus phosphoric acid,
which mass can be easily removed.
III.—Dissolve in hydrochloric acid: Zinc, 50 parts (by weight); sal
ammoniac, 50 parts.
IV.—Hydrochloric acid, 600 parts (by weight); sal ammoniac, 100 parts.
Put zinc chips into the acid to saturation, next add the sal ammoniac.
Filter when dissolved and preserve in flasks.
V.—Eight hundred parts of water with 100 parts of lactic acid and 100
parts of glycerine. This dispenses with the use of chloride of zinc.
«Acid-Free Soldering Fluid.»—I.—Five parts of zinc chloride dissolved
in 25 parts of boiling water. Or, 20 parts of zinc chloride, 10 parts
of ammonia chloride, dissolved in 100 parts of boiling water and put
into glass carboys.
II.—Chloride zinc 1 drachm
Alcohol 1 ounce
«Substitute for Soldering Fluid.»—As a substitute for the customary
soldering fluid and soldering mediums an ammonia soap is recommended,
which is obtained by the mixture of a finely powdered rosin with strong
ammonia solution. Of this soap only the finely divided {660} rosin
remains on the soldered place after the soldering. This soldering
process is well adapted for soldering together copper wires for
electrical conduits, since the rosin at the same time serves as an
insulator.
«FLUXES FOR SOLDERING.»
The fluxes generally used in the soft-soldering of metals are powdered
rosin or a solution of chloride of zinc, alone or combined with sal
ammoniac. A neutral soldering liquid can be prepared by mixing 27 parts
neutral zinc chloride, 11 parts sal ammoniac, and 62 parts water; or, 1
part sugar of milk, 1 part glycerine, and 8 parts water.
A soldering fat for tin-plate, preferable to ordinary rosin, as it can
be more easily removed after soldering, is prepared as follows: One
hundred and fifty parts beef tallow, 250 parts rosin, and 150 parts
olive oil are melted together in a crucible and well stirred, 50 parts
powdered sal ammoniac dissolved in as little water as possible being
added.
Soldering fat for iron is composed of 50 parts olive oil and 50 parts
powdered sal ammoniac. Soldering fat for aluminum is made by melting
together equal parts of rosin and tallow, half the quantity of zinc
chloride being added to the mixture.
Soldering paste consists of neutral soldering liquid thickened with
starch paste. This paste must be applied more lightly than the
soldering liquid.
Soldering salt is prepared by mixing equal parts of neutral zinc
chloride, free from iron, and powdered sal ammoniac. When required for
use, 1 part of the salt should be dissolved in 3 or 4 parts water.
Borax is the flux most frequently used for hard-soldering; it should
be applied to the soldering seam either dry or stirred to a paste with
water. It is advisable to use calcined borax, i. e., borax from which
the water of crystallization has been driven out by heat, as it does
not become so inflated as ordinary borax. Borax dissolves the metallic
oxides forming on the joint.
Finely powdered cryolite, or a mixture of 2 parts powdered cryolite
and 1 part phosphoric acid, is also used for hard-soldering copper and
copper alloys.
Muller’s hard-soldering liquid consists of equal parts of phosphoric
acid and alcohol (80 per cent).
A mixture of equal parts of cryolite and barium chloride is used as a
flux in hard-soldering aluminum bronze.
A very good dry-soldering preparation consists of two vials, one
of which is filled with zinc chloride, and the other with ammonium
chloride. To use, dissolve a little of each salt in water, apply the
ammonium chloride to the object to be soldered and heat the latter
until it begins to give off vapor of ammonium, then apply the other,
and immediately thereafter the solder, maintaining the heat in the
meantime. This answers for very soft solder. For a harder solder
dissolve the zinc in a very small portion of the ammonium chloride
solution (from 1/4 to 1/2 pint).
When steel is to be soldered on steel, or iron on steel, it is
necessary to remove every trace of oxide of iron between the surfaces
in contact. Melt in an earthen vessel: Borax, 3 parts; colophony, 2
parts; pulverized glass, 3 parts; steel filings, 2 parts; carbonate of
potash, 1 part; hard soap, powdered, 1 part. Flow the melted mass on
a cold plate of sheet iron, and after cooling break up the pieces and
pulverize them. This powder is thrown on the surfaces a few minutes
before the pieces to be soldered are brought together. The borax and
glass contained in the composition dissolve, and consequently liquefy
all of the impurities, which, if they were shut up between the pieces
soldered, might form scales, at times dangerous, or interfering with
the resistance of the piece.
To prepare rosin for soldering bright tin, mix 1 1/2 pounds of olive
oil, 1 1/2 pounds of tallow, and 12 ounces of pulverized rosin, and
let them boil up. When this mixture has become cool, add 1 3/8 pints
of water saturated with pulverized sal ammoniac, stirring constantly.
«GAS SOLDERING.»
The soldering of small metallic articles where the production is a
wholesale one, is almost exclusively done by the use of gas, a pointed
flame being produced by air pressure. The air pressure is obtained by
the workman who does the soldering setting in motion a treadle with
his foot, which, resting on rubber bellows, drives by pressure on the
same the aspirated air into wind bellows. From here it is sent into
the soldering pipe, where it is connected with the gas and a pointed
flame is produced. In order to obtain a rather uniform heat the workman
has to tread continually, which, however, renders it almost impossible
to hold the article to be soldered steady, although this is necessary
if the work is to proceed quickly. Hence, absolutely skillful and
expensive hands are required, on whom the employer is often entirely
dependent. To improve {661} this method of soldering and obviate
its drawbacks, the soldering may be conducted with good success in
the following manner: For the production of the air current a small
ventilator is set up. The wind is conducted through two main conduits
to the work tables. Four or six tables may, for instance, be placed
together, the wind and the gas pipe ending in the center. The gas is
admitted as formerly, the wind is conducted into wind bellows by means
of joint and hose to obtain a constant pressure and from here into
the soldering pipe. In this manner any desired flame may be produced,
the workman operates quietly and without exertion, which admits of
employing youthful hands and consequently of a saving in wages. The
equipment is considerably cheaper, since the rubber bellows under the
treadle are done away with.
«GERMAN-SILVER SOLDERS.»
Because of its peculiar composition German-silver solder is related
to the ordinary hard solders. Just as hard solders may be regarded
as varieties of brass to which zinc has been added, German-silver
solders may be regarded as German silver to which zinc has been added.
The German-silver solder becomes more easily fused with an increase
in zinc, and vice versa. If the quantity of zinc be increased beyond
a certain proportion, the resultant solder becomes too brittle.
German-silver solders are characterized by remarkable strength, and are
therefore used not only in soldering German silver, but in many cases
where special strength is required. As German silver can be made of the
color of steel, it is frequently used for soldering fine steel articles.
Solder for ordinary German silver can be made of 1,000 parts
German-silver chips, 125 parts sheet brass chips, 142 parts zinc, and
33 parts tin; or, of 8 parts German silver and 2 to 3 parts zinc.
«Soft German-Silver Solder.»—
I.—Copper 4.5 parts
Zinc 7 parts
Nickel 1 part
II.—Copper 35 parts
Zinc 56.5 parts
Nickel 8.5 parts
III.—German silver 5 parts
Zinc 5 parts
Compositions I and II have analogous properties. In composition III
“German silver” is to be considered as a mixture of copper, zinc, and
nickel, for which reason it is necessary to know the exact composition
of the German silver to be used. Otherwise it is advisable to
experiment first with small quantities in order to ascertain how much
zinc is to be added. The proper proportion of German silver to zinc
is reached when the mixture reveals a brilliancy and condition which
renders it possible to barely pulverize it while hot. A small quantity
when brought in contact with the soldering iron should just fuse.
«Hard German-Silver or Steel Solder.»—
I.—Copper 35 parts
Zinc 56.5 parts
Nickel 9.5 parts
II.—Copper 38 parts
Zinc 50 parts
Nickel 12 parts
Composition I requires a fairly high temperature in order to be melted.
Composition II requires a blow pipe.
«GOLD SOLDERS:»
«Hard Solder for Gold.»—The hard solder or gold solder which the
jeweler frequently requires for the execution of various works, not
only serves for soldering gold ware, but is also often employed for
soldering fine steel goods, such as spectacles, etc. Fine gold is only
used for soldering articles of platinum. The stronger the alloy of the
gold, the more fusible must be the solder. Generally the gold solder is
a composition of gold, silver, and copper. If it is to be very easily
fusible, a little zinc may be added, but, on the other hand, even the
copper is sometimes left out and a mixture consisting only of gold and
silver (e. g., equal parts of both) is used. The shade of the solder
also requires attention, which must be regulated by varying proportions
of silver and copper, so that it may be as nearly as possible the same
as that of the gold to be soldered.
I.—For 24-carat gold: Twenty-two parts gold (24 carat), 2 parts silver,
and 1 part copper; refractory.
II.—For 18-carat gold: Nine parts gold (18 carat), 2 parts silver, and
1 part copper; refractory.
III.—For 16-carat gold: Twenty-four parts gold (16 carat), 10 parts
silver, and 8 parts copper; refractory.
IV.—For 14-carat gold: Three parts gold (14 carat), 2 parts silver, and
1 part copper; more fusible.
V.—Gold solder for alloys containing smaller quantities of gold is
composed {662} of 8 parts gold, 10.5 parts silver, and 5.5 parts
copper, or,
VI.—Ten parts gold (13.5 carat), 5 parts silver, and 1 part zinc.
VII.—The following easily fusible solder is used for ordinary gold
articles: Two parts gold, 9 parts silver, 1 part copper, and 1 part
zinc. Articles soldered with this solder cannot be subjected to the
usual process of coloring the gold, as the solder would become black.
VIII.—A refractory enamel solder for articles made of 20-carat and
finer gold, which can bear the high temperature required in enameling,
consists of 37 parts gold and 9 parts silver, or 16 parts gold (18
carat), 3 parts silver, and 1 part copper.
Which of these compositions should be employed depends upon the degree
of the fusibility of the enamel to be applied. If it is very difficult
of fusion only the first named can be used; otherwise it may happen
that during the melting on of the enamel the soldering spots are so
strongly heated that the solder itself melts. For ordinary articles,
as a rule, only readily fusible enamels are employed, and consequently
the readily fusible enameling solder may here be made use of. Soldering
with the latter is readily accomplished with the aid of the soldering
pipe. Although the more hardly fusible gold solders may also be melted
by the use of the ordinary soldering pipe, the employment of a special
small blowing apparatus is recommended on account of the resulting ease
and rapidity of the work.
«SOLDERS FOR GLASS.»
I.—Melt tin, and add to the melted mass enough copper, with constant
stirring, until the melted metal consists of 95 per cent of tin and 5
per cent of copper. In order to render the mixture more or less hard,
add 1/2 to 1 per cent of zinc or lead.
II.—A compound of tin (95 parts) and zinc (5 parts) melts at 392° F.,
and can then be firmly united to glass. An alloy of 90 parts of tin and
10 parts of aluminum melts at 734° F., adheres, like the preceding, to
glass, and is equally brilliant. With either of these alloys glass may
be soldered as easily as metal, in two ways. In one, heat the pieces
of glass in a furnace and rub a stick of soldering alloy over their
surfaces. The alloy will melt, and can be easily spread by means of a
roll of paper or a slip of aluminum. Press the pieces firmly together,
and keep so until cool. In the other method a common soldering iron,
or a rod of aluminum, is heated over a coal fire, a gas jet, or a
flame supplied by petroleum. The hot iron is passed over the alloy and
then over the pieces to be soldered, without the use of a dissolvent.
Care should be taken that neither the soldering irons nor the glass be
brought to a temperature above the melting point of the alloy, lest the
latter should be oxidized, and prevented from adhering.
«HARD SOLDERS.»
Hard solders are distinguished as brass, German silver, copper, gold,
silver, etc., according to the alloys used (see Brass Solders, Copper
Solders, etc., for other hard solders).
The designation “hard solder” is used to distinguish it from the easily
running and softer solder used by tinsmiths, and it applies solely to
a composition that will not flow under a red heat. For the purposes of
the jeweler solder may be classified according to its composition and
purpose, into gold or silver solder, which means a solder consisting
of an alloy of gold with silver, copper, tin, or zinc-like metal or an
alloy of silver with copper, tin, or zinc-like metal. According to the
uses, the solder is made hard or soft; thus in gold solders there is
added a greater amount of silver, whereas for silver solders there is
added more tin or zinc-like metal.
In the production of solder for the enameler’s use, that is for
combining gold with gold, gold with silver, or gold with copper, which
must be enameled afterwards, it is necessary always to keep in mind
that no solder can be used effectually that contains any tin, zinc,
zinc alloys, or tin or zinc-like metals in any great quantities,
since it is these very metals that contribute to the cracking of the
enamel. Yet it is not possible to do without such an addition entirely,
otherwise the solder would not flow under the melting point of the
precious metals themselves and we should be unable to effect a union
of the parts. It is therefore absolutely necessary to confine these
additions to the lowest possible percentage, so that only a trace is
apparent. Moreover, care must be taken to use for enameling purposes no
base alloy, because the tenacity or durability of the compound will be
affected thereby; in other words, it must come up to the standard.
In hard soldering with borax, direct, several obstacles are encountered
that make the process somewhat difficult. In {663} the first place the
salt forms great bubbles in contact with the soldering iron, and easily
scales away from the surface of the parts to be soldered. Besides
this, the parts must be carefully cleaned each time prior to applying
the salt. All these difficulties vanish if instead of borax we use
its component parts, boric acid and sodium carbonate. The heat of the
soldering iron acting on these causes them to combine in such a way as
to produce an excellent flux, free from the difficulties mentioned.
«Composition of Various Hard Solders.»—Yellow solders for brass,
bronze, copper, and iron:
I.—Sheet-brass chips, 5 parts, and zinc, 3 to 5 parts, easily fusible.
II.—Sheet brass chips, 3 parts, and zinc, 1 part; refractory.
III.—Sheet-brass chips, 7 parts, and zinc, 1 part; very refractory and
firm.
Semi-white solders, containing tin and consequently harder:
I.—Sheet brass, 12 parts; zinc, 4 to 7 parts, and tin, 1 part.
II.—Copper, 16 parts; zinc, 16 parts, and tin, 1 part.
III.—Yellow solder, 20 to 30 parts, and tin, 1 part.
White solders:
I.—Sheet brass, 20 parts; zinc, 1 part, and tin, 4 parts.
II.—Copper, 3 parts; zinc, 1 part, and tin, 1 part.
«To Hard-Solder Parts Formerly Soldered with Tin Solder.»—To repair
gold or silver articles which have been spoiled with tin solder proceed
as follows: Heating the object carefully by means of a small spirit
lamp, brush the tin off as much as possible with a chalk brush; place
the article in a diluted solution of hydrochloric acid for about 8
to 10 hours, as required. If much tin remains, perhaps 12 hours may
be necessary. Next withdraw it, rinse off and dry; whereupon it is
carefully annealed and finally put in a pickle of dilute sulphuric
acid, to remove the annealing film. When the article has been dipped,
it may be hard soldered again.
«SILVER SOLDERS.»
Silver solder is cast in the form of ingots, which are hammered or
rolled into thin sheets. From these small chips or “links,” as they
are called, are cut off. The melted solder can also be poured, when
slightly cooled, into a dry iron mortar and pulverized while still
warm. The solder can also be filed and the filings used for soldering.
Silver solders are used not only for soldering silver objects, but
also for soldering metals of which great resistance is expected. A
distinction must be drawn between silver solder consisting either of
copper and silver alone, and silver solder to which tin has been added.
«Very Hard Silver Solder for Fine Silverware.»—
I.—Copper 1 part
Silver 4 parts
Hard silver solder.
II.—Copper 1 part
Silver 20 parts
Brass 9 parts
III.—Copper 2 parts
Silver 28 parts
Brass 10 parts
Soft silver solder.
IV.—Silver 2 parts
Brass 1 part
V.—Silver 3 parts
Copper 2 parts
Zinc 1 part
VI.—Silver 10 parts
Brass 10 parts
Tin 1 part
These solders are preferably to be employed for the completion of work
begun with hard silver solders, defective parts alone being treated.
For this purpose it is sometimes advisable to use copper-silver alloys
mixed with zinc, as for example:
VII.—Silver 12 parts
Copper 4 parts
Zinc 1 part
VIII.—Silver 5 parts
Brass 6 parts
Zinc 2 parts
This last formula (VIII) is most commonly used for ordinary silverware.
«Silver Solders for Soldering Iron, Steel, Cast Iron, and Copper.»—
I.—Silver 10 parts
Brass 10 parts
II.—Silver 0 parts
Copper 30 parts
Zinc 10 parts
III.—Silver 30 parts
Copper 10 parts
Tin 0.5 parts
IV.—Silver 60 parts
Brass 60 parts
Zinc 5 parts
{664}
In those solders in which brass is used care should be taken that none
of the metals employed contains iron. Even an inappreciable amount of
iron deleteriously affects the solder.
V.—Copper, 30 parts; zinc, 12.85 parts; silver, 57.15 parts.
VI.—Copper, 23.33 parts; zinc, 10 parts; silver, 66.67 parts.
VII.—Copper, 26.66 parts; zinc, 10 parts; silver, 63.34 parts.
VIII.—Silver, 66 parts; copper, 24 parts, and zinc, 10 parts. This very
strong solder is frequently used for soldering silver articles, but can
also be used for soldering other metals, such as brass, copper, iron,
steel band-saw blades, etc.
IX.—Silver, 4 parts, and brass, 3 parts.
X.—A very refractory silver solder, which, unlike the silver solder
containing zinc, is of great ductility and does not break when
hammered, is composed of 3 parts silver and 1 part copper.
«Soft Silver Solders.»—I.—A soft silver solder for resoldering parts
already soldered is made of silver, 3 parts; copper, 2 parts, and zinc,
1 part.
II.—Silver, 1 part, and brass, 1 part; or, silver, 7 parts; copper, 3
parts, and zinc, 2 parts.
III.—A readily fusible silver solder for ordinary work: Silver, 5
parts; copper, 6 parts, and zinc, 2 parts.
IV.—(Soft.) Copper, 14.75 parts; zinc, 8.20 parts; silver, 77.05 parts.
V.—Copper, 22.34 parts; zinc, 10.48 parts; silver, 67.18 parts.
VI.—Tin, 63 parts; lead, 37 parts.
«French Solders for Silver.»—I.—For fine silver work: Fine silver, 87
parts; brass, 13 parts.
II.—For work 792 fine: Fine silver, 83 parts; brass, 17 parts.
III.—For work 712 fine: Fine silver, 75 parts; brass, 25 parts.