Part 320

«Marine Paint to Resist Sea Water.»—First prepare the water-resisting agglutinant by heating together

Dry white lead, carbonate only 1 part Litharge 1 part Linseed oil (fluid measure) 14 parts

Heat these and stir until of the consistency of thick glue, and for every 36 parts, by weight, of this compound add 3 parts, by weight, of turpentine, and 1 part, by weight, of mastic varnish (mastic rosin dissolved in turpentine); reheat the whole, and for every 32 parts, by weight, stir in and mix the following:

Baked and powdered clay 4 parts Portland cement 16 parts Zinc white 1 part Red lead 1 part

After well mixing, dilute with more or less turpentine (not exceeding 25 per cent of the whole), or linoleate of manganese, the latter being preferable, as it has greater binding power. For colored paints use red oxide of iron or green oxide of chrome, but do not use chrome green or lead, as they will not stand the action of the sea water.

«Compositions for Ships’ Bottoms.»—

Green.

Pale rosin 25 pounds Prepared mineral green 8 pounds D. L. zinc 13 pounds Boiled oil 2 pounds Mineral naphtha 1 gallon Petroleum spirit 1 1⁠/⁠2 gallons

Prepared Mineral Green.

Dry levigated mineral green 28 pounds Turpentine 7 pounds Turpentine varnish 7 pounds Refined linseed oil 7 pounds

Copper Color.

Pale rosin 25 pounds Light Italian ocher 15 pounds D. L. zinc 5 pounds Turkey red paint 1⁠/⁠2 pound Petroleum spirit 1 1⁠/⁠2 pounds Mineral naphtha 1 pound

Pink.

Pale rosin 25 pounds D. L. zinc 16 pounds Deep vermilion 7 pounds Mineral naphtha 1 gallon Petroleum spirit 1 1⁠/⁠2 gallons

«PAINTS FOR WALLS OF CEMENT, PLASTER, HARD FINISH, ETC.»

«Coating for Bathrooms.»—As a rule cement plastering, as well as oil paint, suffices for the protection of walls and ceilings in bathrooms, but attention must be called to the destructive action of medicinal admixtures. For such rooms as well as for laboratories, an {499} application of Swedish wood tar, made into a flowing consistency with a little oil of turpentine and put on hot, has been found very excellent. It is of advantage previously to warm the wall slightly. To the second coat add some wax. A very durable coating is obtained, which looks so pleasing that it is only necessary to draw some stripes with a darker paint so as to divide the surface into fields.

«Cement, to Paint Over Fresh.»—The wall should be washed with dilute sulphuric acid several days before painting. This will change the surplus caustic lime to sulphate of lime or gypsum. The acid should be about one-half chamber acid and one-half water. This should be repeated before painting, and a coat of raw linseed oil flowed on freely should be given for the first coat. While this cannot be always guaranteed as effectual for making the paint hold, it is the best method our correspondent has heard of for the purpose, and is worth trying when it is absolutely necessary to paint over fresh cement.

«Damp Walls, Coating for.»—Thirty parts of tin are dissolved in 40 parts of hydrochloric acid, and 30 parts of sal ammoniac are added. A powder composed of freestone, 50 parts; zinc oxide, 20 parts; pounded glass, 15 parts; powdered marble, 10 parts; and calcined magnesia, 5 parts, is prepared, and made into a paste with the liquid above mentioned. Coloring matter may be added. The composition may be used as a damp-proof coating for walls, or for repairing stonework, or for molding statues or ornaments.

«Facade Paint.»—For this zinc oxide is especially adapted, prepared with size or casein. Any desired earth colors may also be added. The surfaces are coated 3 times with this mass. After the third application is dry, put on a single coating of zinc chloride solution of 30° Bé. to which 3 per cent borax is added.

This coating is very solid, can be washed, and is not injured by hydrogen sulphide.

«Hard-Finished Walls.»—The treatment for hard-finished walls which are to be painted in flat colors is to prime with a thin coat of lead and oil well brushed into the wall. Next put on a thin coat of glue size; next a coat mixed with 1⁠/⁠3 oil and 2⁠/⁠3 turpentine; next a coat of flat paint mixed with turpentine. If you use any dry pigment mix it stiff in oil and thin with turps. If in either case the paint dries too fast, and is liable to show laps, put a little glycerine in, to retard the drying.

«PAINTS, WATERPROOF AND WEATHERPROOF:»

See also Fireproof Paint.

The following are claimed to be both waterproof and weatherproof:

I.—In 50 parts, by weight, of spirit of 96 per cent, dissolve 16 parts, by weight, of shellac, orange, finely powdered; 3 parts, by weight, of silver lake, finely powdered; and 0.6 parts, by weight, of gamboge, finely powdered. This paint may be employed without admixture of any siccative, and is excellently adapted for painting objects which are exposed to the inclemencies of the weather, as it is perfectly weatherproof.

II.—Mix glue water with zinc oxide (zinc white) and paint the respective object with this mixture. When this is dry (after about 2 hours) it is followed up with a coating of glue water and zinc chloride in a highly diluted state. Zinc oxide enters into a chemical combination with zinc chloride, which acquires the hardness of glass and a mirror-like bright surface. Any desired colors can be prepared with the glue water (size) and are practically imperishable. This zinc coating is very durable, dries quickly, and is 50 per cent cheaper than oil paint.

«Water- and Acid-Resisting Paint.»—Caoutchouc is melted with colophony at a low temperature, after the caoutchouc has been dried in a drying closet (stove) at 158° to 176° F., until no more considerable increase in weight is perceptible, while the colophony has completely lost its moisture by repeated melting. The raw products thus prepared will readily melt upon slight heating. To the melted colophony and caoutchouc add in a hot liquid state zinc white or any similar pigment. Thin with a varnish consisting of 50 parts of perfectly anhydrous colophony, 40 parts of absolute alcohol, and 40 parts of benzine. The whole syrupy mass is worked through in a paint mill to obtain a uniform product, at which operation more or less colophony varnish is added according to the desired consistency.

«Water- and Air-Proof Paint.»—An air-proof and waterproof paint, the subject of a recent French patent, is a compound of 30 parts, by weight, acetone; 100 parts acetic ether; 50 parts sulphuric ether; 100 parts camphor; 50 parts gum lac; 200 parts cotton; 100 parts paper {500} (dissolved in sulphuric acid); 100 parts mastic in drops. These proportions may fluctuate according to need. The paper is reduced well and dissolved without heat with sufficient sulphuric ether; the cotton is dissolved in the acetone and the whole is mixed together with the other ingredients and stirred well. The application is performed as with any other varnish. The coating is said not to crack or shrink and to be particularly useful as a protection against moisture for all stuffs.