Page:The Building News and Engineering Journal, Volume 22, 1872.djvu/103

 Fes. 2, 1872. THE BUILDING NEWS. 87 vessel, care being taken that none of the yolk is mixed with the white, as that would spoil it for our purpose. Half a pint of water must now be added to the white of the egg and well beaten up until the mixture becomes entirely a white froth; this is best done by putting into the mixture a common sash tool (hog’s-hair), and holding the handle between the palms of both hands and twirling it about ; the circular motion spreads the hairs of the brush, and effectually churns the egg and water into froth. Sometimes potato water is used for this purpose. A slice of raw potato is scraped into warm water, which takes out some of the starch; this is thinned down and brushed over the work. In other cases French chalk in powder is dusted over the work from a pounce bag, but this is not a clean method, and is seldom used except by sign writers. Of course, whichever size is used, it must be washed off with warm water after the work is gilt. The work to be gilt is now well rubbed over with this froth until every part is covered; it will dry partially dead. This egg size answers two purposes. It will effectually prevent the gold sticking to any part but the oil gold size, which in nine cases out of ten it would do if it were not for chis precaution ; and in the second place the egg size deadens the gloss, and causes the oil size to lay on the work without contracting or (technically) sizing, for it is a fact that if oil size is put upon an oil or gloss ground, the size will con- tract and become full of holes. This is the reason why in varnishing anything it is best, and in almost all cases indispensable, when two coats of varnish are used, that the first coat should be damped down with a damp chamois or wash leather just previous to putting on the second coat. If this is not done, the second coat is almost sure to size or contract. Another method of gilding on varnished or polished grounds, such as enamelled doors, japanners’ work, &c., is to lay on the gold with the isinglass size in the same manner as before described for gilding on glass. When the gold is laid on it must be well sized with the isinglass size ; the design or letters to be gilt must then be either pounced or traced on to the gold, and pencilled in with either white hard varnish, Canada balsam, or other clear varnish, which may be afterwards removed with spirits of wine, naphtha, or turpentine. When the design is pencilled in and is dry, all the gold-leaf left uncovered may be washed off with a sponge and water or damp cotton- wool, which will retain or gather up the ‘superfluous gold, so that none may be wasted. When the work is washed perfectly clean from the gold, the varnish or stopping may be removed with a camel'’s-hair tool and turpentine or spirits of wine, according to the nature of the varnish. When the whole of the varnish is cleaned thoroughly from the gold, the ornament will appear in bright burnished gold, and may then be varnished or polished in the usual way, The advantage of this system lies in the fact that the isinglass size does not interfere with the smoothness of ‘the surface to be gilt upon, consequently the gold, being laid upon a polished surface, whether of glass, varnish, paint, enamel, glazed earthenware, or other surface, will retain all the advantages of the smooth surface, in addition to its own lustre, without the use of the burnisher. Before leaving this part of our subject we would make a suggestion in reference to all gilding or lacquering done upon iron or brass work, or intended to be placed in churches or other large buildings where many people frequent, and which are not used daily and thus kept dry. We haye found, in our ex- perience, especially in churches, that corro- sion takes place on painted and gilt standards, coronae, brackets, &c., in course of two or three years, more or less according to the dampness or dryness of the church. The rust shows itself first on black spots, then it rises up into little knobs, scales, &c., and falls off, and has to be redone. <As a rule these things are painted in dead or flat colour, having a little gold size mixed with it to bind it. This it does to a cer- tain degree, but is utterly useless as a protection to the iron, as the damp soon penetrates through or is partially absorbed into its body, reaches the surface of the iron, and decay or oxidation at once commences, and when once it has started it is the most difficult thing imaginable to stop its ravages. We have a theory that the moisture con- densed upon the iron work in churches, con- sequent upon their being necessarily colder than the air which surrounds them, is im- pregnated with the gases evolved from the human body and the breath, leaving a deposit upon them eyery time it is made damp, and which ultimately reaches the iron. The best preventative we have hitherto found is to coat the new iron with one or two bare coats of well-boiled linseed oil with a little burnt umber added ; two coats will be better than one, but both must be rubbed on the work as barely as possible, else the desired end will not be obtained. When this is thoroughly dry and hard it may be painted and gilt in the usual manner, and it will then haye some chance of standing, not otherwise. Lacquered brass and copper work will also be affectedin the same mannerasiron, or rather from the same cause, and we have found that if the lacquered work is coated with copal yar- nish before being exposed to the impure air of a church, it will keep its lustre for almost any length of time. The varnish interferes so little with its lustre that the fact of its being varnished would never be detected. All polished brasswork (except it is regularly polished) should be varnished when used in churches or other public buildings. A very simple and effectual method of renovating brasswork, and also making a permanent job of it, is as follows: If the brasswork— whether it be a chandelier, a pendant, a corona, or lamp, lacquered—is in imitation of bronze, the article must be well washed, or put to soak in a strong solution of common soda and soft soap, or soda and quicklime ; this would clean off all the verdigris or canker from the metal, leaving it smooth and free from any trace of rust. It must now be well washed in clean water, and dried and rubbed with sawdust. All those parts which are to retain the bright colour of the brass must now be polished up with fine emery paper, then with a soft rag and a little whiting or any other polishing powder, until the part becomes of a bright burnish. While in this state it should be coated with two coats of white hard varnish, or the best pale copal, which will preserve the brilliancy of the metal and prevent its corrosion. The other parts of the articles may now be painted in with any shade of bronze-colour paint, and varnished. A capital series of bronze colours for this purpose may be made from a mixture of burnt umber, Brunswick green, Indian red, and yellow ochre. By adding more or less of any one of the above colours an infinite variety of tints or tones of bronze paint may be produced, and varied at pleasure. We come now to bronze powders or bronz- ing. Bronzing or gilding with bronze powders is manipulated in various ways for different purposes. The house decorator either lays a size of the same kind as for oil gilding, or he varnishes his work, and when the varnish has arrived at a certain state of dryness or tacki- ness, he then uses a strip of wash-leather, which he folds in a convenient form, then takes up a little of the powder upon the leather and gently rubs it upon the parts of the work intended to be bright; these are generally the most prominent parts of the article, or those parts which catch and reflect the light best. The superfluous powder is then carefully brushed off, and the work should then be varnished, especially if it is outside work. size, or japanners’ gold size, the size need only be picked in on exactly those parts required to be covered with the bronze powder, and if Of course, if we use oil gold | grease. the groundwork is gloss colour it will require to be egg size, or the same as for gold ; but if the colour is dead, it will need no size. But the very best system of bronzing (if it may be so called), and the most permanent, is done as follows :—First put in roughly with the oil gold size all those parts intended to be bright of, say, a balustrade or ornamental banister of a staircase, the prominent parts; gild these in the usual way when the size is dry enough. When gilt, give the gold a coat of clear parch- ment size as before described ; then one coat of some clear, hard-drying varnish. When this is dry, paint over the whole of the gilt and ungilt parts with the bronze colour required, or two colours may be used if the article will allow such treatment. Now wipe off the bronze colour from off as much of the parts gilt as is necessary to accomplish the desired end, taking it clean off the tops and graduating the tint by dabbing with the rag over the end of the thumb. If this is done carefully and with judgment, a most excellent effect may be gained with a brilliancy and a permanency not to be got by any other method we are aware of on paintwork. The work may now either be varnished or left as it is, as may be desirable. A very fair and quiet imitation of bronze may be done in paint alone; by first painting the article with a gold colour, and then when that is dry, painting over the gold colour with the bronze colour, and wiping the latter off all those parts which give the prominent lines and detail of the ornament. ‘The effect will, of course, depend upon the judicious choice of the colours used, and the taste and skill exercised in the wiping off the paint. This may be done with either dead or gloss colour and afterwards varnished. Bronze powders are used for the bronzing of fenders, hat-stands, and many other cast- iron articles. ‘This bronzing is generally done by the japanners, and is varnished, and then stoved to harden the whole. It may be ob- served that in using any colour of bronze powder the colour of the bronze paint should be in accordance with it, so that there may be harmony between the two. Copper bronze or gold bronze, or in fact any other colour of bronzing, should appear to grow out of the painted part, just as if the bright parts were formed by abrasion or wear; and as the body of the metal would become bright by rubbing in real bronze, the bright parts gra- duate into the darker parts, and so it should appear in the imitation. The lithographer and printer use large quantities of bronze powder for not only labels, show-cards, and such like goods, but also for the highest class of illuminated works. In this case a size is printed either from type or from the lithographic stone on to the sheets to be bronzed; these stones, unless they are sufficiently dry and are rubbed over with the bronze powder, which is done by dipping a hare’s foot (soft and furry) into the bronze and then rubbing it over the size, the super- flous bronze is then brushed off on to another sheet so that no waste may occur; a boy will thus cover a great number of sheets in a day’s time. Hundreds of thousands of labels for packing needles, hair-pins, and fancy goods of both hard and soft wares are done in this manner and at a surprisingly small cost. It must be understood that the paper in these cases is specially prepared to receive the size to secure the bronze; if it were not so, the gold size would sink into the paper and the work be spoiled. All those parts of any works on paper which are to be bronzed or gilt must be previously prepared to receive the oil or japanners’ gold size ; this may be done either by coating over the exact space to be gilt or bronzed with one or two coats of shellac yarnish (i.e., patent knotting), white hard yarnish, gum, isinglass or parchment size, or any other glutinous substance free from These all act as a support and eroundwork for the gold or bronze, and, by using a little spent glass-paper to take off any inequalities left by the size