25.—Before the application of the finishing size, any imperfectly covered places must be regilded, using for a size the Japan gold size. This size sets in about an hour, and for that reason is preferable to the ordinary oil-size. The places to be regilt should be first gone over with shellac varnish. Whenever gold is to be regilt, it must be gone over with shellac, as otherwise it will have a greasy appearance.
26.—Old frames that are to be regilt, should be first washed clean and free from dirt, and then be given a coat of shellac before the oil-size is applied. Where any burnish has been, it must, of course, be washed off before the reburnishing can be done.
Some gilders use shellac varnish in place of the clear size, to size the frame for the oil gilding. It works well enough on the composition parts, but on the flats and hollows it dries so rapidly that it leaves ridges and inequalities to such an extent that the smoothness of the work is spoiled. For quick work, however, and by using the shellac very sparingly and giving two coats of it, very good results are to be had.
27.—Flats are generally matted. Occupying, as they do, a prominent and conspicuous position, being next to the picture which is to occupy the frame, they require to be very perfectly done, and they are therefore done in water-gilt, and subsequently matted with a coat and sometimes with two of ormolu. The flat to be matted is proceeded with as follows:
After all imperfections have been removed, it must be rubbed smooth with very fine sand paper and polished with a moist rag. Three coats of burnish-size are then applied very evenly and smoothly to it, avoiding all marks of the brush where possible; or two coats of yellow clay, prepared in the same manner as the burnish-size, and afterwards two coats of burnish-size, are given. When the final coat is sufficiently dry, the flat must be polished with a piece of coarse paper, or it may even be burnished, when time is no object. If the inside edge should be intended to be burnished after being laid in gold, that part must not be polished, nor receive the coat of very thin glue water, which is to be applied after the polishing process to all that part which is to be matted. This coat of glue water must be applied very evenly and freely to the flat, avoiding bubbles if possible. When dry, the flat is all laid in gold in the same manner as proceeded with when laying the gold for the burnish work.
28.—The best plan to lay a perfect flat is to double-gild it, which consists in simply laying on another coat of gold after the first has dried. The first coat when dry, as well as the second, must be rubbed smooth with a wad of cotton batting. Care must be exercised during this process, in order to avoid, as much as possible, disturbing the lay. To lay a second coat over the first, the gin-water must be washed over at once, so as to avoid washing up the gold leaf.
29.—After the gold has been rubbed smooth with the cotton, a coat of ormolu must be applied to the unburnished part, to impart to it the matted appearance required. The ormolu should be applied warm and by means of a camel’s hair brush, and the application must be very nicely and carefully done.
30.—The following is the manner in which the ormolu is prepared:
Take a teaspoonful of either the tincture of gum benzoin or of white shellac varnish, and mix it in a cup with about twice or three times its bulk of the highest proof alcohol. Now have ready a hot solution of glue or of gelatine, of about the same strength as that of the finishing size. The quantity should be about one-half a teacupful. This must be poured quickly and all at once into the solution of the gum benzoin or of shellac, and the result will be a perfect emulsion of the gum, which will be of a milky white appearance. This, of course, should be strained, and is to be applied as already described. If the first coat should appear spotty and streaky, a second one will be necessary. In applying either the finishing size or the ormolu, it is well to have a lump of alum convenient, to which, from time to time, the brush may be applied. This will, in the case of either, cause it to go on in a better manner and to lay more evenly.
The ormolu, as prepared by the above method, will keep for any length of time. It may also be slightly colored, if it be desired to give the gold a deeper tinge.