« PreviousContinue »
Japanning is properly the art of varnishing and painting ornaments on wood, in the same manner as is done by the natives of Japan in the East Indies.
The substances which admit of being japanned are almost all kinds that are dry and rigid, or not too flexible ; as wood, metals, leather, and paper prepared. Wood and metals do not require any
preparation but to have their surfaces perfectly even and clean ; but leather should be securely strained, either on frames or on boards; as its bending, or forming folds, would otherwise crack and force off the coats of varnish. Paper should be treated in the same manner, and have a previous strong coat of some kind of size; but it is rarely made the subject of japanning till it is converted into papier maché, or wrought by other means into such form, that its original state, particularly with respect to flexibility, is changed.
One principal variation from the method formerly used in japanning is, the omitting any prim. ing, or undercoat, on the work to be japanned. In the older practice, such a priming was always employed; the use of it was to economize the varnish by filling up the inequalities in the surface. But there is a great inconvenience arising from the use of it, that the japan coats are constantly liable to be cracked and peeled off by any violence, and will not last near so long as the articles which are japanned without any such priming.
The French still retain the use of this undercoat, and their japanned goods are upon that
account less durable than those manufactured at Birmingham, where it is not used.
Of the Nature of Japan Grounds.
When a priming is used, the work should first be prepared by being well smoothed with fish-skin or glass-paper, and being made thoroughly clean, should be brushed over once or twice with hot size, diluted with two-thirds water, if it is of the common strength. The priming should then be laid on as even as possible, and should be formed of a size, of a consistency between the common kind and glue, mixed with as much whiting as will give it a sufficient body of colour to hide the surface of whatever it is laid upon, but not more. This must be repeated till the inequalities are completely filled up, and then the work must be cleaned off with Dutch rushes, and polished with a wet rag.
When wood or leather is to be japanned, and no priming is used, the best preparation is to lay two or three coats of coarse ,varnish, composed in the following manner:
Take of rectified spirits of wine one pint, and of coarse seed-lac and resin, each two ounces ; dissolve the seed-lac and resin in the spirit, and then strain off the varnish.
This varnish, as well as all others formed of spirit of wine, must be laid on in a warm place; and if it can be conveniently managed, the piece of work to be varnished should be made warm likewise ; and for the same reason, all dampness should be avoided; for either cold or moisture chills this kind of varnish, and prevents its taking proper hold of the substance on which it is laid.
When the work is so prepared, or by the priming with the composition of size and whiting above described, the proper japan ground must be laid on, which is much the best formed of shelllac varnish, and the colour desired, except white, which requires a peculiar treatment; and if brightness be wanted, then also other means must be pursued. The colours used with the shell-lac varnish
may be any pigments whatever which give the tint of the ground desired.
As metals never require to be under-coated with whiting, they may be treated in the same manner as wood or leather.
White Japan Grounds. The difficulty of forming a ground that shall be at the same time hard and white, arises from there being no substance that will form a very hard varnish, and yet have no colour. The best is made as follows; Mix flake white, or white lead, with onesixth of its weight of starch, and dry the mixture, and temper it with mastich varnish. Lay this on the substance to be japanned, with or without the under coat of whiting; then varnish it with five or six coats of a varnish made by dissolving two ounces of picked lac, and three ounces of gum animi, in a a quart of spirit of wine, straining off the clear varnish.
A very good varnish, free from all brittleness, may be formed, by dissolving as much
animi as the oil will take, in old nut, or poppy oil, boiled gently, when the
put into it. The ground of white colour may be laid on in this varnish, and then a coat or two may be put over the ground:
but it must be well diluted with oil of turpentine when it is used.
Blue Japan Grounds. Blue japan grounds may be formed of bright Prussian-blue; or of verditer, glazed over by Prussian-blue, or smalt. The colour may be best mixed with shell-lac varnish, and brought to a polishing state by five or six coats of varnish of seed-lac; but the varnish, nevertheless, will somewhat injure the colour, by giving to a true blue a cast of green, and fouling in some degree a warm blue by the yellow it contains; where, therefore, a bright blue is required, and a less degree of hardness can be dispensed with, the method before directed in the case of white grounds must be pursued,
Red Japan Grounds. For a scarlet japan ground, vermilion may be used; but the vermilion has a glaring effect, that renders it much less beautiful than the crimson produced by glazing it over with carmine or fine lake, or even with rose pink, which has a very good effect, used for this purpose. For a very bright crimson, nevertheless, instead of glazing with car, mine, the Indian lake should be used, dissolved in the spirit of which the varnish is compounded, which it readily admits of when good; and in this case, instead of glazing with the shell-lac varnish, the upper, or polishing coats need only be used, as they will equally receive and convey the tinge of the Indian lake, which may be actually dissolved by spirits of wine, and this will be found a much cheaper method than the using carmine. If, how. ever, the highest degree of brightness is required, the white varnish must be used.
Yellow Japan Grounds. For bright yellow grounds, king's yellow, or turpeth mineral should be employed, either alone or mixed with fine Dutch pink, and the effect may be still more heightened, by dissolving powdered turmeric root in the spirits of wine, of which the upper or polishing coat is made; which spirits of wine must be strained from off the dregs, before the seed-lac be added to it, to form the varnish.
The seed-lac varnish is not equally injurious here, and with greens, as is the case of other colours; because, being only tinged with a reddish yellow, it is little more than an addition to the force of the colours.
Yellow grounds may be likewise formed of Dutch pink only, which, when good, will not be wanting in brightness, though extremely cheap.
Green Japan Grounds.
Green grounds may be produced by mixing king's yellow and bright Prussian blue, or rather turpeth-mineral and Prussian blue. And a cheap, but fouler kind by verdigris, with a little of the above mentioned yellows, or Dutch pink. But where a very bright green is wanted, the crystals of verdigris, called distilled verdigris, should be employed; and to heighten the effect, they should be laid on a ground of leaf gold, which renders the colour extremely brilliant and pleasing.
Orange Japan Grounds. Orange coloured japan grounds may be formed by mixing vermilion, or red lead, with king's yel.