Painting on Glass and Porcelain. (IV)

Manufacturer and builder 12, 1876

Continued from page 250.

An soon as the artist has become perfectly familiar with the various colors he is to employ, and the various specimens of which we spoke in our former article have been made with care, he must proceed to outline on the piece to be decorated the subject which ho has chosen, and which he first must have very carefully drawn and colored on paper.

As the lead-pencil slides over the counsel without making a mark, the piece must be first prepared; this is done by passing lightly over it a piece of rag imbibed with spirits of ordinary turpentine, to which some more fatty, thick turpentine has been added. After having allowed it to dry for some minutes, the spirits evaporate, and there remains on the enamel a kind of crust, on which it is easy to draw with a lead-pencil, whether an ordinary or a lithographic one. But it is better to make on thin paper of vegetable fiber the outlines of the objects to be represented. and then to transfer these on the porcelain, or rather on the prepared layer of turpentine above described, in the following way: first a thin blackleaded paper is pet on the porcelain, and on top of this the drawing; both are fixed is place with little balls of molding-wax at the corners, then with a fine but blunt ivory point the outlines are traced, and by this means the lines passed over by the point will be sorbed on the porcelain.

Another way especially adapted for ornaments with repeated figures, is to employ paper in which the outlines are perforated with needle-holes; this is best done by having a needle fixed in a wooden handle like a lead pencil. After smoothing the back of the paper (where the needle has elevated the edges around the holes) wills a piece of fine and flat pumicestone, it is fixed with wax to the porcelain, and a fine powder passed over it — say pulverized black lead, black chalk, or any other suitable material; this limy be done by means of small woollen rag or a roller, when the powder, penetrating through the holes, becomes fixed on the transparent coating and shows the outlines of the drawing. Of course a dark powder is used on a white ground, and white powder on a dark colored piece of porcelain.

The outlines of the drawing being reproduced on the porcelain by one of tile above means, they are made more permanent by passing over them carmin, or some vegetable water-color, made more serviceable by mixing it with a little dextrin. Some artists even finish the picture in water-color, which however they use sparingly, but which in the end is burned out at the final operation. As the water-color is not removed by spirits of turpentine, this offers the advantage that the ground can be cleaned by means of the latter before the painting has been commenced, and the wrong pencil marks removed, as well as the black dust which will always adhere after the use of the perforated paper and its annexes.

It may he well also to trace the outlines with the enamel colors, using such as arc prominent in the object to be painted; but many practical porcelain painters are satisfied that it is better to use water-color first, which besides has the advantage of being transparent and shows the original line its case it is covered up too broadly.

It often happens that the whole or a large part of the piece to be decorated has to receive a ground color, intended to bring certain colors out better, or to temper the crudeness of the white ground. We will say a few words concerning the manner of operating in this case, and the precautions necessary to obtain a good result, which is by no means very easy.

For the Background. — For the background square or flat brushes are used, large enough to cover its a short time the surfaces to be painted. The color is sufficiently tempered with additional drops of lavender oil, which prevents a too rapid drying; the brush is dipped into it, and the surface equally covered with continuous strokes, evenly distributed, while taking care not to cover the same surface twice. This done, one of the blenders, of which we have spoken before on page 132, is taken, kept perpendicularly to the surface painted, and this surface tapped by light perpendicular touches or blows, so as to equalize the color; it is best to tap first the middle part of the colored layers, and then the corners, taking care to clean the blender often, so as to prevent the color from adhering and thus removing too much from the surface. After this the same operation is repeated with a smaller brush with shorter hair, so as to bring the particles constituting the color closer together and to make a uniform surface in which special particles are nearly invisible. A background, in order to be a success, must always be made in one operation, and quickly; it is therefore necessary to prepare an amount of color rather too abundant than too scant, so as to finish it at once without being compelled to prepare more color and commence again.

When an ornamental or other figure is to be represent, on a background, the porcelain is always first entirely covered with the some, as explained; if the background is too opaque to show a design previously made, this previous operation may be omitted, and the design carefully transferred or traced on the background after this if it is well dried, in the manner described, care being taken not to remove or injure in any way the color of the background.

The parts of the background outside the design are then covered with water color, and when everything is well dried (usually the next day) the figures of the design are painted over with a varnish mixed with oil of lavender; this will in a short time soften the background under it, and it may then be removed with a clean muslin rag; then the clean white porcelain will appear again, where the figures have to be painted and they will then appear as represented in Fig. 5, white on a dark background, and these are then painted with the enamel color selected, as represented in Fig. 6, where also a part is seen at the right as it appears when the perforated paper, in which the figure has been pricked, has been applied.

Further operations will be explained in future issues.

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