Brass, Silver, & lacquer finishes.
FINISHES FOR BRASS ONLY
The foregoing recipes are for copper and brass where so stated
and the following are for brass only:
- No. 1. To obtain a dark antique finish on brass
apply butter
of antimony to the brass and allow it to dry.
- No. 2. A steel blue color can be produced on brass by immersing
in the following solution : sodium hyposulphite, 4 ounces ;
acetate of lead, 2 ounces; water, 2 quarts. This solution is
used hot. Various colors can be obtained by varying the degree
of heat and the time of immersion.
- No. 3. To dull brass apply with a brush the following solution
12 parts hydrochloric acid, 1 part ferric oxide. Apply with
a brush.
- No. 4. A slightly different result may be obtained by adding
to the above recipe one part of white arsenic.
- No. 5. A solution for coloring brass steel gray: dissolve
4 ounces of muriate of arsenic in 2 quarts of water and immerse
the articles.
- No. 6. The so-called Flemish gray on brass is obtained by
dipping in the following solution: muriatic acid, 1/2 ounce;
white arsenic, 1/4 ounce; potassium sulpluret, 6 grains; water,
2 gallons, Mix the arsenic in the acid, add the water, then the
potassium.
- No. 7. Brown to red shades for brass: dissolve 8 ounces nitrate
of iron and 8 ounces of hyposulphite of soda in 2 quarts of water.
- No. 8. Black to brown shades for brass: dissolve 3 ounces
nitrate of iron and 2 ounces perchloride of iron in 3 quarts
of water.
- No. 9. For a golden bronze color on brass: dissolve: 3 pounds
nitrate of potash in 2 quarts of sulphuric acid, then add 2 gills
of nitric acid and 2 gills of hydrochloric acid.
- No. 10. For a bright green: dissolve 1/2 pound sal ammoniac
and 1/2 pound sulphate of copper in 2 quarts of boiling water.
Apply with a stiff brush and allow to dry.
- No. 11. A duller green can be produced by dissolving 4 ounces
sulphate of copper in 2 quarts of boiling water. Immerse the articles
and allow them to dry.
- No. 12. Still another method is to immerse the articles in
a hot solution consisting of hyposulphite of soda, 4 ounces;
nickel salts, 4 ounces; water, 2 quarts. After immersion in the
solution dip the articles in clean boiling water.
- No. 13. There is one very interesting method of coloring brass
that has no distinctive name, and that is to copper plate the
brass and then to polish off the copper plate on the high spots
leaving the copper plate in the background, and then to lacquer
the work. This makes a very effective finish and is one that
is not commonly known.
The method is as follows : mix together
1/2 pint sulphuric acid and 2 pints of water; add 1 tablespoonful
sulphate of copper crystals. After the piece of brass work has
been thoroly cleaned, wind around it a, piece of thin iron wire
or a narrow strip of sheet iron, and place in the solution for
about 15 minutes. This will copper
plate the article. Dry with a cloth, polish all in one direction
with a piece of smooth emery cloth, and lacquer and wax. If the solution
gets worn out put in more sulphate of copper.
There
is an interesting chemical fact in connection with this kind of
copper plating, and that is that the sulphate of copper is simply
copper in another form, suspended in the solution, but the iron displaces
or precipitates it and deposits it on the copper, or upon any piece
of iron that is held in the solution. This is a practical application
of the "electromotive series" of chemistry in
which the metals are arranged) as follows: magnesium, aluminum,
manganese, zinc, chromium, cadmium, iron, cobalt, nickel, tin,
lead, hydrogen, arsenic, copper, antimony, bismuth, mercury, silver,
platinum, gold. Each metal displaces from a solution
those following it in the series, and is displaced by those preceding
it. Iron precedes copper in the foregoing series; therefore it displaces
copper from solution.
FINISHES FOR SILVER
To oxidize silver any of the following may be used :
No. 1. Dissolve in 1 pint of water I cubic inch of sulphide
of potassium, and apply to the silver.
No. 2. Slightly warm the silver article and apply hyposulphuret
of ammonium.
No. 3. Dissolve a pinch of chloride of platinum in a cupful of
warm water and apply to the silver. The disadvantage of this
recipe is that any platinum compound is very expensive.
No. 4. Place the silver in a small closed box with a piece of
sulphide of potassium.
No. 5. Dissolve a pinch of barium sulphide in a cupful of warm
water. Apply to the silver.
No. 6. Dissolve a punch of ammonium sulphide in a cupful of warm
water, and apply to the silver.
When using any of the above solutions to color silver, if the
color is not dark enough add more of the chemical and if it is
too dark weaken by adding water. To clean silver that is tarnished
dip in a solution of 1 1/2 pounds of cyanide of potassium dissolved
in 1 gallon of water.
Aluminum can be cleaned by immersing in a solution of caustic
soda. To frost aluminum dissolve 2 ounces of caustic soda in
I pint of water. A formula for blackening or oxidizing
aluminum is as follows: chloride of zinc, 1 pound; sulphate of
copper, I ounce; hot water, 2 quarts. Dip the articles in the solution.
If the metal does not turn black fast enough, add a little more
sulphate of copper.
As a last word of advice on the coloring of any metal, be sure
that the chemicals are fresh, as almost all of the chemicals
used in coloring deteriorate with age or exposure to the air.
LACQUERING AND WAXING
Lacquer serves on metal the same purpose that varnish does on
wood; that is, preserves the color and the finish. The commercial
lacquers are rather expensive and are not always easy to obtain.
- No. 1. Banana oil, sometimes called bronzing liquid, makes
a fairly good lacquer for our purpose, and it has the decided
advantage of being obtainable in almost any drug store.
- No. 2. A fair lacquer can be made from white shellac and grain
alcohol mixed together in the proportion of 5 ounces of white
shellac to 2 quarts of grain alcohol Allow the mixture to stand
for about 48 hours, then strain thru a double thickness of
cheese cloth, and it is ready for use.
- No. 3. Another lacquer is made up of the following : alcohol,
2 quarts; seed-lac, 5 ounces; gum copal, 1/2 ounce. Allow the
mixture to stand, stirring occasionally until the seed-lac
and the gum are dissolved, then strain thru cheese cloth.
- No. 4. Collodion thinned down with grain alcohol also makes
a good lacquer.
- No. 5. A gold colored lacquer for brass only is made of the
following : spirits of wine, 2 quarts ; tumeric, 6 ounces ;
gamboge, 1/2 ounce; sandarac resin, 12 ounces; shellac, 4 ounces;
turpentine resin, 5 ounces. Allow the ingredients to dissolve
and strain.
- No. 6. Another good lacquer for brass or copper: I part of
spirits of wine; mastic resin, 8 ounces; gum camphor, 6 ounces;
sandarac resin, 1 pound; white shellac, 1 pound. Allow the
mixture to dissolve and strain.
FINISHING WITH WAX
The best method of wax finishing is to heat the article hot enough
just to melt the wax as it is applied with a cloth, then lightly
and rapidly apply the wax to the metal. Allow it to get perfectly
cold, then polish lightly with a soft cloth. The best wax to
use is Johnson's black furniture wax, altho a good wax can be
made by melting together equal amounts of beeswax and turpentine.
Naphtha may be used in place of the turpentine.
Metal articles may be refinished by applying a thin coat of any
of the above waxes applied cold.
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