To make waterproof paint for plaster get some mica plates, bleach them by fire, boil in hydrochloric acid, wash and dry and reduce to a fine powder; then mix with sufficient quantity of collodion to make it run from the brush. Apply with ordinary paint brush. F. L. Engel.
New Britain, Conn.
To make a paint for fitting and scraping get five or ten cents' worth of scarlet vermilion (powder) at any store where paint is sold. Melt a tablespoonful of lard and mix into the dry paint until like thick cream, and when cold it is just right. The vermilion is very fine and has no grit in it so that the least touch of the mixture shows.
This is better than the tube paint generally used, as being mixed with animal oil, it will stand exposure to the air for a year or more without drying; but the tube paint is mixed with vegetable oil and will soon harden on exposure to the air. Any colored paint powder can be used, which is preferred. To test for grit take some between the thumb and forefinger. P. W. B.
Persons having occasion to paint oil wells of bearings, or any surface coming in contact with either hot or cold oil, will find a zinc paint consisting of 25 pounds oxide of zinc, 3 gallons gloss oil, and 1 quart linseed oil, cut with turpentine, and bleached with ultramarine blue, to be one of the best coverings ever made. The surface to be covered should be absolutely free of all greasy or oily substances; if proper care is taken, the paint will not crack and will retain its pure white appearance indefinitely. The paint can be blown into water jackets of bearings, filling the sand holes, and as it dries rapidly, will be found excellent for the purpose. Electro.
In shops making a business of repairing machinery, it is generally necessary to mark the parts of machines in some way so that they may be properly reassembled. This is especially true in railway shops, where the marking is necessary more for the purpose of distinguishing the parts of different engines. The best way to mark such parts, of course, is to stamp them with steel dies; but this is not always practicable, and, in the absence of such means of marking, it is customary to use a marking paint made of white lead mixed with turpentine to a thin consistency. Such paint dries quickly and when dry is not easily removed. It has the advantage of showing up fairly well on greasy surfaces, but it is better that the surfaces to be marked should be well cleaned with kerosene oil before marking.
Newark, N. J, P. Emerson.
Half a bushel unslaked lime; slake with warm water, cover it during the process to keep the steam; strain the liquid through a fine sieve or strainer; add a peck of salt, the same to be previously well dissolved in warm water; add three pounds of ground rice boiled to a thin paste and stir in boiling hot; add one-half pound of glue which has been previously dissolved over a slow fire and add five gallons of hot water to the mixture. stir well and let it stand for a few days, covering, up to keep out dirt. It should be put on hot. One pint of the mixture, properly applied, will cover a square yard. Small brushes are best. There is nothing can compare with it for outside or inside work and it retains its brilliancy for many years. Coloring matter may be put in and made of any shade - Spanish brown, yellow ochre, or common clay, etc.
U. S. Grant. To my dear friend, I. Bulson,
San Francisco. P. S.: I whitewashed the White House all over with it U. S. G.
To prepare a marking paint for use on stone where exposed to the water and dampness, use pitch, 11 pounds, lampblack, 1 pound, and heat carefully, adding sufficient turpentine to give the mixture the desired consistency. M. B. Canek.
To prepare whitewash for fences, buildings, shop interiors, etc., that will not flake and fall off, mix 1 part fine Portland cement with about 8 gallons whitewash. The cement binds the whitewash to the wood and makes a permanent covering which is unaffected by weather conditions. The small quantity of cement used and the constant stirring necessary to keep the whitewash in good condition for applying, prevents the cement hardening in lumps at the bottom of the pail, as might be expected. M. E. Canek.