With this the work can be done in one coat. This method of finishing is usually employed on the cheaper class of toys where it isn't advisable to apply an expensive finish.
20. Another Suggestion for Finishing.—Tint a gallon of benzine or gasoline with chrome green, chrome yellow, and vermilion, ground in Japan until the desired shade is obtained. This formulae is especially good for dipping purposes.
21. Use of Paint.—Although paint can be bought ready prepared and in any color, as has been stated, it is advisable to have the students mix their own colors and choose their own color scheme.
22. Ingredients of good Paint.—The best paints are usually made by mixing together white lead, linseed oil, pigment of the desired color (colors ground in oil), and a drier.
While white lead is sufficient as the pigment for white paint, a better result is obtained by mixing zinc oxide with the white lead. These two substances have the convenient property of balancing each other's disadvantages. For instance, zinc oxide has a tendency to crack and to peal, which is overcome by the tougher coating formed by the white lead. Again, when white lead is exposed to light and weathering, it becomes chalky, which fault is remedied by the property possessed by zinc oxide, of remaining hard.
The linseed oil used is obtained from flaxseed by pressing the thoroly ground seed. About twenty-three gallons of oil can be obtained from one bushel of the seed. By boiling the oil with lead oxide or manganese oxide it can take more oxygen from the air, and thereby its drying powers are increased.
Driers are substances that absorb oxygen from the air and give part of it to the oil. The raw linseed oil absorbs the oxygen from the air very slowly, but the addition of turpentine is a great aid in overcoming this defect.
To insure the best results in painting, one must first consider the kind and condition of the surface to be painted, and to what use the toy will be put; then decide on the proper composition and consistency of the paint.
23. Application of Paint.—In applying the paint to the toy the first coat should be thinned. This will act as a primer or undercoat for the succeeding coats of paint. Care should be taken that plenty of time is allowed between coats for the paint to dry thoroly. Three coats of paint will produce a good finish.
24. Preparation of surface.—All woodwork must be sanded and thoroly dry before any paint is applied. Care should be taken to see that all knots and sappy streaks shall be covered with a coat of orange shellac. Then apply the first coat.