THE GILDING PROCESS
I will now proceed to give a list and description of the various implements and materials which are reequired in the process of gilding picture frames.
1.-A GILDING CUSHION, on which to lay the leaves of gold preparatory to cutting them into the sizes required for laying. This may be procured already made. It is made of a board one half inch thick and nine and one-half inches long by five and one-half inches wide, covered with buckskin and padded with several thicknesses of Canton flannel. It usually has a shield of parchment, about four inches high, on one end, to protect the leaves from currents of air. Underneath, is a loop lor the thumb, which is to be inserted in it when the cushion is to be held in the band. There is also another loop to hold the gilding knife when not in use.
2.-A GILDING KNIFE, for cutting the gold leaf. It should be double-edged and have a tolerably keen edge; not so much so as to cut the cushion, but suffficiently so to divide the leaf without tearing it. When it becomes dull it may be readily sharpened by rubbing the edges with a piece of very fine sand paper.
3.-BRUSHES, both bristle and camel’s hair. Nummbers 4 and 5, of the bristle brushes, flat, are the sizes mostly required, either for applying the white coat or the oil-size. For the camel’s hair brushes, numbers 4,5 and 6 are very useful, as well as a number 6 or 8 lettering pencil (brush); also several fitch blenders, numbers 9 and 10 are good sizes; procure one of each.
4.-BURNISHERS. These must be of several shapes and sizes. Every gilder will become accustomed to some particular shape and size, and practice only will determine the most desirable one; but for ordinary use, the following shapes and sizes will be found sufficient for almost any work: burnishers The burnishers should be made of flint, though agate is frequently used, particularly for burnishing silver leaf. They should be securely fastened in wooden handles by means of brass ferrules. These handles, as well as the stones, frequently become loosened from continual use and require refastening. This is done by renewing the filling with gum shellac or powdered rosin, and applying sufficient heat to set the stones. On cooling, they will be found to be again firm in their sockets. The same method may be pursued with regard to the handle. A little brick-dust mixed with the resin gives a more secure hold. Burnishers, contrary to the general opinion of those who manufacture and sell them,should not be too highly polished, but the surface should be rather dull, as in this condition they take n. better hold on the gold. If they have too much polish, they glide over the leaf without burnishing it. The polish may be subdued or removed by rubbing the burnishers with crocus martis and oil spread upon a chamois-skin. Care must, of course, be exercised in the operation, or too much of the polish will be removed and the burnisher will require to be repolished. It is, perhaps, needless to say that the burnishers should be kept scrupulously clean and free from everything like moisture and grease.
5.-TIPS. These are made of both camel’s hair and badger hair. They are used to lift the gold leaf from the cushion, after it has been suitably cut, and to apply it to the surface preparedto receive it. When they do not freely take up the leaf, it is customary to pass them across the hair of the head, when they receive suffiicient electricity from it to attach the gold at once to them. This attraction has been attributed to the moisture which the tips receive from the hair, but I think the notion is a mistaken one. The tips eviidently become dectrified, for they will, in that condition, attract the gold at some distance off. Moisture would not produce this effect. The camel’s hair tips are the best to use. Several of them will be required. It is a good plan to cut an old one down to within an inch and a half of the paste-board handle, and so use it, when very narrow slips of the leaf are being used; they can be lifted better and more safely with such a contrivance. In all cases, the tip should not be applied to more of the gold to be raised by it than is actually necessary for the purpose.
6.-SOME GLUE, of the best white quality. Many gilders use gelatine instead of glue. For mixing with the burnish-size, the gelatine is undoubtedly the more desirable. The glue should be naturally white, not artificially so colored; and it should be free from all grit and sediment. Cooper’s make, of both glue and gelatine, is undoubtedly the best, for all purposes of gilding. It acts more uniformly and is altogether the most reliable.
7.-PIPE CLAY, for coating the composition parts of the frame. It usually comes in lumps and must be allowed to soak before mixing. The pipe clay has superseded the use of whiting for the two primary white coats to a frame. It is free from all grit, whilst whiting is not, and it gives a soft, smooth surface for the layer of gold leaf.
8.-PARIS WHITE, or whiting. This is used for stopping up holes and other imperfections in the frame. It has more body than the pipe clay, and for that reason is used instead of it. Paris white is simply whiting precipitated in powder, and it is consequently freer from grit and other impurities.
9.-OIL-SIZE. This is used for giving the adhesive coat to which the gold is applied when laid in oil.
10.-BURNISH-SIZE. Used for giving the coat to which the gold is applied when a burnished surface is required.
11.-COTTON BATTING, of a good quality. This is used for presising down the goldleaf when it is being laid in oil.
12.-GOLD LEAF, of the best quality of deep-colored gold. The leaf comes done up in books of twenty-five leaves each, and made into packs of twenty books each.
13.-AN OX-GALL, strained into a bottle, with about two teaspoonfuls of carbolic acid to preserve it from decomposition. This, mixed with the white coat and the clear size, will prevent pin-holes and frothing. Some gilders use alcohol and even spirits of turpenntine for this purpose; vinegar has also been recommmended, but, after a thorough trial of all of them, I feel confident that the best results will be had with the ox-gall.
14.-CARBOLIC ACID. The crystallized form is the best to use. It comes in bottles of a pound weight. It must be melted by placing the bottle in hot water and, when the fluid condition takes place, add some water, when the whole mass will remain fluid. This is a perfect antiseptic and very useful to mix with the glue and gelatine, which are thereby preserved from decomposition.
15.-SAND PAPER; numbers O, and 1.
16.-ALCOHOL, of the highest proof. This is used in laying the gold leaf which is to be burnished.
17.-JAPAN gold size.
18.-SHELLAC VARNISH, both the brown and the white.
19.- BURNISH-SIZE STRAINER.
20.-SEVERAL CUPS, for mixing the different pre parations. It is well to have covers for them, as all the preparations should be effectually protect, from dust.
21.-A GRADUATED GLASS MEASURE; one of four ounces capacity is the most useful.
22.-SPOONS, for mixing with. The tea size is the best for general use. do not return any that may be left, back to the origginal vessel containing the size. Pay no attention to the skin which from time to time forms on the surface, when not in use. II. The burnish-size should be always kept in a china or earthenware jar. If kept in a tin vessel, its moisture causes the tin to rust, and the deposit caused by the rust is highly injurious to the size. The oil-size may be kept in a tin vessel provided with a cover. When this size is required for use, it should be thoroughh1y stirred up, as the coloring matter of which it is in part composed, being the heaviest, has a tendency to settle and to leave the pure oil on the surface. Take out only a sufficient quantity for immediate use, as dries quite rapidly, particularly in warm weather and do not return any that maybe left, back to the original vessel containing the size. Pay no attention to the skin which from time to time forms on the surface, when not in use.