(2257) Japanning Metallic Objects.

Manufacturer and builder 1, 1879

— The Japan varnish is put on with a brush, as is done with all articles that are not coated by being dipped. But the essential point to which japanning differs from ordinary varnishing, is to place the objects covered in an oven or hot chamber called "stove," heated to about 600° Fah., or such a high temperature as can safely be employed without injuring the article or causing the varnish to run off or blister. Metallic articles require no other preparation than cleaning, and if it is desired to have them perfectly black, it is well to give them a preparatory coating of the varnish mixed with fine ivory black, as a simple coating of the japan varnish alone is not black enough, but somewhat transparent. After the objects are coated place them in the "stove" and bake until the varnish is quite bard. You can obtain this varnish at any paint store behind the age. If there are none of this kind in your neighborhood, you will have to make it yourself. For this purpose you have to proceed as follows: Melt 5 pounds of Naples asphaltum, 1 pound of dark gum anime, pour them into 1½ gallons of linseed oil, and boil for two hours; then melt 1 pound of dark amber resin and boil with 2 pints of linseed oil; add the latter solution to the forner, and boil for another two hours, or until a little of the mass, when cooled, can be rolled into pills. Then withdraw it from the fire, and when cold dissolve in spirits of turpentine. The quantity here given is about enough for 8 gallons of turpentine. Some varnishers add a little "dryer," consisting of linseed oil boiled with lead oxid. They put this into the klinseed oil with which the asphaltum is boiled. The advantage of thin addition is that it considerably shortens the time during which the objects have to be baked in the "stove."

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