(2021) Gilding with Gold Leaf.

The Manufacturer and Builder 1, 1878

— There are various methods applicable, according to the various circumstances and the variety of objects to be gilded. Bookbinders use the gold leaf in two ways — to gild on the edge and to place gold letters on the binding. To gild on the edge, the edge is smoothly cut, put in a strong press, scraped so as to make it solid, and the well beaten white of an egg or albumen put on thinly; the gold leaf is then put on before the albumen is dry; it is pressed down with cotton, and when dry polished with an agate polisher. To put on the lettering, the place where the letters are to appear is coated with abumen, and after it is dry, the type to be used heated to about the honing point of water, the gold leaf put on, either on the book or on the type, and then pressed on the place where the lettering is desired, when the gold leaf will adhere by the heat of the type, while the excess of gold leaf loosely around is rubbed off with a loft of cotton. To do printing with gold leaf, the sheet to be printed upon is pinned to the tympan of a hand-press, and it is fleet piloted with ink of any color, or with varnish, then the typo is covered with a large sheet of paper, the gold leaf laid on, and the tympan laid down again, slowly and carefully, so as not to disturb the gold leaf by motions of the air; then the pressure is again applied, when the gold leaf will stick to the printed sheet, and the surplus can be rubbed off with a tuft of cotton. In gilding picture-frames with gold leaf there are two methods; other with the ordinary gold size, and the other with varnish. The latter method does not allow polishing, but is water-proof; the former is not. Tho main point is to have a well prepared ground-work of say while lead and drying oil, smoothed down properly; then follow several coats of calcined white lead in linseed oil and turpentine, with intervals of at least 24 hours between each coat, which moat be carefully smoothed off with pumice-stone and fine emery-paper. Then the gold size is applied, which may be made from the sediment that collects at the bottom of the pot in which painters wash their brushes; this is thoroughly ground and strained. When the gold size coat is sufficiently dry so as to be still a little sticky, apply the gold leaf and press it on with cotton or a soft brush; after a few days' hardening it is varnished with spirit or oil varnish. This gives a water-proof gilding, but ordinarily picture-frames are gilded with gold size containing no oil. It is made of finely ground sal ammoniac, to which is added a very little beef suet; this is mixed with a pallet-knife, with parchment dissolved in water, so as to flow from the knife when hot. The frame may be prepared first with a few coats of Paris white and glue-water, rubbed down smoothly, and finally apply the size, which must not be tow thick, as then it will chip off, and if too thin it will not have sufficient body. The must difficult part in a11 these operations of gold leaf gilding, is the application of the gold leaf, which requires much practice, judgment, and great care, but with some attention to little details it can be easily learned. There ought to be no draught at the place of operation, and the operator ought to avoid allowing his breath to blow upon the gold leaves, as they are so thin and light that the least breath of air causes them to fly about — worse then feathers. Turn the gold leaves — one at a time — out of the book upon the leather cushion; with the gilding-knife you may lift any leaf and carry it to a convenient place to cut it into the sizes required. Blow gently on the center of the leaf and it will at once spread out and lie fiat without any wrinkles, then cut it by passing the edge of the knife over it until divided. Plate the work to be gilded as near as practicable in a horizontal position, and with a long camel's-hair pencil, dipped in a mixture of water with a little brandy, go over as much surface as the piece of gold is to cover; then take up the gold from the cushion with a tip. Drawing it over the forehead and cheek will dampen it sufficiently to make the gold adhere. This must them be carefully transferred to its place on the work, and by gently breathing on it, it will adhere. Take care that the part to which it is to be applied be sufficiently wet, so that the gold leaf will not crack. Proceed in this way a little at a time, not attempting to cover too much art once. If any cracks or flaws appear, immediately apply another piece of gold leaf over it — large enough to cover the crack. If occasionally the gold does not appear to adhere, on account of the ground having become, too dry, run a wet pencil chase to the edge of the gold, eo as to allow water to penetrate under the gold leaf. When the work is dry, (say in 10 or 13 hours), it may bo burnished with agate tool, taking care to first remove all dust from the tool as well as from the gilded surface.

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