A good varnish for steel may be made by dissolving 10 parts of clear grains of mastic, 5 parts of camphor, 15 parts of san-darac, and 5 parts of elemi in a sufficient quantity of grain alcohol. Apply the varnish without heat. Jos. M. Stabel.
Rochester, N. Y.
To make a varnish for outdoor wood and ironwork, dissolve in about 2 pounds of tar oil ½ pound of aspbaltum and a like quantity of pounded rosin; mix hot in an iron kettle, care being taken to prevent any contact with the flame. When cold the varnish is ready for use.
Rochester, N. Y. Joseph M. Stabel.
A good varnish for finishing metals can be made by mixing 1,000 parts of benzine, 300 parts of pulverized asphalt, and 6 parts of pure india rubber, to which is added enough lampblack to give the desired consistency to the mixture.
Bridgeport, Conn. H. A. Sherwood.
Dissolve by gentle heat 8 ounces of san-darac in 32 ounces of alcohol. Another receipt is: Dissolve 2 pounds of mastic and 2 pounds of a lammar in 1 gallon turpentine without heat. The drawings must first be sized with a strong solution of isinglass and hot water. W. R. Bowers. Birmingham, Eng.
For small cast iron patterns the following is a very satisfactory method of varnishing. Apply boiled linseed oil to the iron, the pattern being heated to a temperature that will just char or blacken the oil; the oil appears to enter the pores of the iron, and after such an application the metal resists rust and corrosive agents very satisfactorily. James A. Pratt.
Howard, R. I.
Even with the best of care the patternmaker will find his shellac, leaving dirty streaks on the pattern from various impurities held in suspension in the varnish. These may be entirely precipitated by the gradual addition of some crystals of oxalic acid, stirring the varnish to aid their solution, and then setting it aside over night to permit the impurities to settle. No more acid should be used than is really necessary. Oscar E. Perrigo. Neponset, Mass.
A good black varnish for cast iron and forgings can be made of ¼ pound lampblack; ½ pound rosin; 1 pound asphaltum; 1 quart turpentine spirits; and a small quantity linseed oil. The lampblack is first rubbed up with the linseed oil, no more oil being used than necessary for this purpose. The other ingredients are then mixed with it thoroughly. O. G.
The appearance of varnished blue-prints and drawings may be greatly improved and the amount of bleached shellac varnish considerably decreased by the following process: Soak overnight a quantity of isinglass in just enough cold water to cover it. Use a perfectly clean glue kettle, in which it is to be heated up, adding whatever amount of water may be needed to make a moderately thin sizing. Apply this warm, not hot, to the drawing or blueprint. When dry apply one good coat of bleached shellac varnish. The effect will be nearly as good as the best varnished maps. Oscar E. Perrigo.