Stained Glass Work: A text-book for students and workers in glass

CHAPTER V

Cutting (advanced)—The Ideal Cartoon—The Cut-line—Setting the Cartoon—Transferring the Cut-line to the Glass—Another Way—Some Principles of Taste—Countercharging.

We have only as yet spoken of the processes of cutting and painting in themselves, and as they can be practised on a single bit of glass; but now we must consider them as applied to a subject in glass where many pieces must be used. This is a different matter indeed, and brings in all the questions of taste and judgment which make the difference between a good window and an inferior one. Now, first, you must know that every differently coloured piece must be cut out by itself, and therefore must have a strip of lead round it to join it to the others.

Draw a cartoon of a figure, bearing this well in mind: you must draw it in such a simple and severe way that you do not set impossible or needlessly difficult tasks to the cutter. Look now, for example, at the picture in Plate V. by Mr. Selwyn Image—how simple the cutting!

You think it, perhaps, too "severe"? You do not like to see the leads so plainly. You would like better something more after the "Munich" school, where the lead line is disguised or circumvented. If so, my lesson has gone wrong; but we must try and get it right.

You would like it better because it is "more of a picture"; exactly, but you ought to like the other better because it is "more of a window." Yes, even if all else were equal, you ought to like it better, because the lead lines cut it up. Keep your pictures for the walls and your windows for the holes in them.

But all else is not equal: and, supposing you now standing before a window of the kind I speak of, I will tell you what has been sacrificed to get this "picture-window" "like a picture." Stained-glass has been sacrificed; for this is not stained-glass, it is painted glass—that is to say, it is coloured glass ground up into powders and painted on to white sheets of glass: a poor, miserable substitute for the glorious colour of the deep amethyst and ruby-coloured glasses which it pretends to ape. You will not be in much danger of using it when you have handled your stained-glass samples for a while and learned to love them. You will love them so much that you will even get to like the severe lead line which announces them for what they are.

But you must get to reasonably love it as a craft limitation, a necessity, a thing which places bounds and limits to what you can do in this art, and prevents tempting and specious tricks.

How to Make a "Cut-line."—But now, all this being granted, how are we to set about getting the pieces cut? First of all, I would say that it is always well to draw most, if not all, of the necessary lead lines on the cartoon itself. By the necessary lead lines I mean those which separate different colours; for you know that there must be a lead line between these. Then, when these are drawn, it is a question of convenience whether to draw in also the more or less optional lead lines which break up each space of uniform colour into convenient-sized pieces. If you do not want your cartoon afterwards for any other purpose you may as well do so: that is, first "set" the cartoon if it is in charcoal or chalk, and then try the places for these lead lines lightly in charcoal over the drawing: working thus, you can dust them away time after time till they seem right to you, and then either set them also or not as you choose.

A good, useful setting-mixture for large quantities is composed by mixing equal parts of "white polish" and methylated spirit; allowing it to settle for a week, and pouring off all that is clear. It is used in the ordinary way with a spray diffuser, and will keep for any length of time.

The next step is to make what is called the cut-line. To do this, pin a piece of tracing-cloth over the whole cartoon; this can be got from any artist's-colourman or large stationer. Pin it over the cartoon with the dull surface outwards, and with a soft piece of charcoal draw lines 1/16 to 1/8 of an inch wide down the centre of all the lead lines: remove the cloth from the cartoon, and if any of the lines look awkward or ugly, now that you see them by themselves undisguised by the drawing below, alter them, and then, finally, with a long, thin brush paint them in, over the charcoal, with water-colour lamp-black, this time a true sixteenth of an inch wide. Don't dust the charcoal off first, it makes the paint cling much better to the shiny cloth.

When this is done, there is a choice of three ways for cutting the glass. One is to make shaped pieces of cartridge-paper as patterns to cut each bit of glass by; another is to place the bits of glass, one by one, over the cut-line and cut freehand by the line you see through the glass. This latter process needs no description, but you cannot employ it for dark glasses because you cannot see the line through: for this you must employ one of the other methods.

How to Transfer the Cutting-line on to the Glass.—Take a bit of glass large enough to cut the piece you want; place it, face upwards, on the table; place the cut-line over it in its proper place, and then slip between them, without moving either, a piece of black "transfer paper": then, with a style or hard pencil, trace the cutting-line down on to the glass. This will not make a black mark visible on the glass, it will only make a grease mark, and that hardly visible, not enough to cut by; but take a soft dabber—a lump of cotton-wool tied up in a bit of old handkerchief—and with this, dipped in dry whitening or powdered white chalk, dab the glass all over; then blow the surface and you will see a clear white line where the whitening has stuck to the greasy line made by the transfer paper; and by this you can cut very comfortably.

But a third way is to cut the shape of each piece of glass out in cartridge-paper; and to do this you put the cut-line down over a sheet of "continuous-cartridge" or "cartoon" paper, as it is called, and press along all the lines with a style or hard pencil, so as to make a furrow on the paper beneath; then, after removing the cut-line, you place a sheet of ordinary window-glass below the paper and cut out each piece, between the "furrows" leaving a full 1/16 of an inch. This sixteenth of an inch represents the "heart" or core of the future lead; it is the distance which the actual bits of glass lie one from the other in the window. You must use a very sharp penknife, and you will find that, cutting against glass, each shape will have quite a smooth edge; and round this you can cut with your diamond.

This method, which is far the most accurate and craftsmanly way of cutting glass, is best used with the actual diamond: in that case you feel the edge of the paper all the time with the diamond-spark; but in cutting with the wheel you must not rest against the edge of the paper; otherwise you will be sure to cut into it. Now, whichever of all these processes you employ, remember that there must be a full 1/16 of an inch left between each piece of glass and all its neighbours.

The reason why you leave this space between the pieces is that the core of the lead is about that or a little less in thickness: the closer the glass fits to this the better, but no part of the glass must go nearer to its neighbour than this, otherwise the work will be pressed outwards, and you will not be able to get the whole of the panel within its proper limits.

Fig. 34.

Fig. 34 is an illustration of various kinds and sizes of lead; showing some with the glass inserted in its place. By all means make your leads yourself, for many of those ready made are not lead at all, or not pure lead. Get the parings of sheet lead from a source you can trust, and cast them roughly in moulds as at fig. 35. Fig. 36 is the shears by which the strips may be cut; fig. 37 is the lead-mill or "vice" by which they are milled and run into their final shape; fig. 38 the "cheeks" or blocks through which the lead passes. The working of such an instrument is a thing that is understood in a few minutes with the instrument itself at hand, but it is cumbrous to explain in writing, and not worth while; since if you purchase such a thing, obviously the seller will be there to explain its use. Briefly,—the handle turns two wheels with milled edges 1/16 of an inch apart; which, at one motion, draw the lead between them, mill it, and force it between the two "cheeks" (fig. 38), which mould the outside of the lead in its passage. These combined movements, by a continuous pressure, squeeze out the strip of lead into about twice its length; correspondingly decreasing its thickness and finishing it as it goes.

Fig. 35.

Fig. 36.

Fig. 37.

Some principles of good taste and common sense with regard to the cutting up of a Window; according to which the Cartoon and Design must be modified.—Never disguise the lead line. Cut the necessary parts first, as I said before; cut the optional parts simply; thinking most of craft-convenience, and not much of realism.

Fig. 38.

 

Do not, however, go to the extent of making two lead lines cross each other. Fig. 39 shows the two kinds of joint, A being the wrong one (as I hold), and B the right one; but, after all, this is partly a question of taste.

Do not cut borders and other minor details into measured spaces; cut them hap-hazard.

Fig. 39.

Do not cut leafage too much by the outlines of the groups of leaves—or wings by the outlines of the groups of feathers.

Do not outline with lead lines any forms of minor importance.

Do not allow the whole of any figure to cut out dark against light, or light against dark; but if the figure is ever so bright, let an inch or two of its outline tell out as a dark against a spot of still brighter light; and if it is ever so dark, be it red or blue as strong as may be, let an inch or two of its outline tell out against a still stronger dark in the background, if you have to paint it pitch-black to do so.

By this "countercharging" (as heralds say), your composition will melt together with a pleasing mystery; for you must always remember that a window is, after all, only a window, it is not the church, and nothing in it should stare out at you so that you cannot get away from it; windows should "dream," and should be so treated as to look like what they are, the apertures to admit the light; subjects painted on a thin and brittle film, hung in mid-air between the light and the dark.

CHAPTER VI

Painting (advanced)—Waxing-up—Cleanliness—Further Methods of Painting—Stipple—Dry Stipple—Film—Effects of Distance—Danger of Over-Painting—Frying.

I have mentioned all these points of judgment and good taste we have just finished speaking of, because they are matters that must necessarily come before you at the time you are making the cartoon, the preliminary drawing of the window, and before you come to handle the glass at all.

But it is now necessary to tell you how the whole of the glass, when it is cut, must be fixed together, so that you can both see it and paint upon it as a whole picture. This is done as follows:—

First place the cut-line (for the making of which you have already had instructions) face upwards on the bench, and over it place a sheet of glass, as large at least as the piece you mean to paint. Thick window-glass, what glass-makers call "thirty-two ounce sheet"—that is, glass that weighs about thirty-two ounces to the square foot—will do well enough for very small subjects, but for anything over a few square feet, it is better to use thin plate-glass. This is expensive, but you do not want the best; what is called "patent plate" does quite well, and cheap plate-glass can often be got to suit you at the salvage stores, whither it is brought from fires.

Having laid your sheet of glass down upon the cut-line, place upon it all the bits of glass in their proper places; then take beeswax (and by all means let it be the best and purest you can get; get it at a chemist's, not at the oil-shop), and heat a few ounces of it in a saucepan, and when all of it is melted—not before, and as little after as may be—take any convenient tool, a penknife or a strip of glass, and, dipping it rapidly into the melted wax, convey it in little drops to the points where the various bits of glass meet each other, dropping a single drop of wax at each joint. It is no advantage to have any extra drops along the sides of the bits; if each corner is properly secured, that is all that is needed (fig. 40).

Some people use a little resin or tar with the wax to make it more brittle, so that when the painting is finished and the work is to be taken down again off the plate, the spots of wax will chip off more easily. I do not advise it. Boys in the shop who are just entering their apprenticeship get very skilful, and quite properly so, in doing this work; waxing up yard after yard of glass, and never dropping a spot of wax on the surface.

It is much to be commended: all things done in the arts should be done as well as they can be done, if only for the sake of character and training; but in this case it is a positive advantage that the work should be done thus cleanly, because if a spot of wax is dropped on the surface of the glass that is to be painted on, the spot must be carefully scraped off and every vestige of it removed with a wet duster dipped in a little grit of some kind—pigment does well—otherwise the glass is greasy and the painting will not adhere.

Fig. 40.

For the same reason the wax-saucepan should be kept very clean, and the wax frequently poured off, and all sediment thrown away. A bit of cotton-fluff off the duster is enough to drag a "lump" out on the end of the waxing-tool, which, before you have time to notice it, will be dribbling over the glass and perhaps spoiling it; for you must note that sometimes it is necessary to re-wax down unfired work, which a drop of wax the size of a pinhole, flirted off from the end of the tool, will utterly ruin. How important, then, to be cleanly.

And in this matter of removing such spots from fired work, do please note that you should use the knife and the duster alternately for each spot. Do not scrape a batch of the spots off first and then go over the ground again with the duster—this can only save a second or two of time, and the merest fraction of trouble; and these are ill saved indeed at the cost of doing the work ill. And you are sure to do it so, for when the spot is scraped off it is very difficult to see where it was; you are sure to miss some, in going over the glass with a duster, and you will discover them again, to your cost and annoyance, when you matt over them for the second painting: and, just when you cannot afford to spare a single moment—in some critical process—they will come out like round o's in the middle of your shading, compelling you to break off your work and do now what should have been done before you began to paint.

But the best plan of all is to avoid the whole thing by doing the work cleanly from the first. And it is quite easy; for all you have to do is to carry the tool horizontally till it is over the spot where you want the wax, and then, by a tilt of the hand, slide the drop into its place.

Further Methods of Painting.—There are two chief methods of treating the matt—one is the "stipple," and the other the "film" or badgered matt.

The Stipple.—When you have put on your matt with the camel-hair brush, take a stippling brush (fig. 41) and stab the matt all over with it while it is wet. A great variety of texture can be got in this way, for you may leave off the process at any moment; if you leave it off soon, the work will be soft and blurred, for, not being dry, the pigment will spread again as soon as you leave off: but, if you choose, you can go on stippling till the whole is dry, when the pigment will gather up into little sharp spots like pepper, and the glass between them will be almost clear. You must bear in mind that you cannot use scrubs over work like the last described, and cannot use them to much advantage over stipple at all. You can draw a needle through; but as a rule you do not want to take lights out of stipple, since you can complete the shading in the single process by stippling more or less according to the light and shade you want.

Fig. 41.

A very coarse form of the process is "dry" stippling, where you stipple straight on to the surface of the clear glass, with pigment taken up off the palette by the stippling brush itself: for coarse distant work this may be sometimes useful.

Now as to film. We have spoken of laying on an even matt and badgering it smooth; and you can use this with a certain amount of stipple also with very good effect; but you are to notice one great rule about these two processes, namely, that the same amount of pigment obscures much more light used in film than used in stipple.

Light spreads as it comes through openings; and a very little light let, in pinholes, through a very dark matt, will, at a distance, so assert itself as to prevail over the darkness of the matt.

It is really very little use going on to describe the way the colour acts in these various processes; for its behaviour varies with every degree of all of them. One may gradually acquire the skill to combine all the processes, in all their degrees, upon a single painting; and the only way in which you can test their relative value, either as texture or as light and shade, is to constantly practise each process in all its degrees, and see what results each has, both when seen near at hand and also when seen from a distance. It is useless to try and learn these things from written directions; you must make them your own, as precious secrets, by much practice and much experiment, though it will save you years of both to learn under a good master.

But this question of distance is a most important thing, and we must enlarge upon it a little and try to make it quite clear.

Glass-painting is not like any other painting in this respect.

Let us say that you see an oil-painting—a portrait—at the end of the large room in some big Exhibition. You stand near it and say, "Yes, that is the King" (or the Commander-in-Chief), "a good likeness; however do they do those patent-leather boots?" But after you have been down one side of the room and turn round at the other end to yawn, you catch sight of it again; and still you say, "Yes, it's a good likeness," and "really those boots are very clever!" But if it had been your own painting on glass, and sitting at your easel you had at last said, "Yes,—now it's like the drawing—that's the expression," you could by no means safely count on being able to say the same at all distances. You may say it at ten feet off, at twenty, and yet at thirty the shades may all gather together into black patches; the drawing of the eyelids and eyes may vanish in one general black blot, the half-tones on the cheeks may all go to nothing. These actual things, for instance, will be the result if the cheeks are stippled or scrubbed, and the shade round the eyes left as a film—ever so slight a film will do it. Seen near, you see the drawing through the film; but as you go away the light will come pouring stronger and stronger through the brush or stipple marks on the cheeks, until all films will cut out against it like black spots, altering the whole expression past recognition.

Try this on simple terms:—

Do a face on white glass in strong outline only: step back, and the face goes to nothing; strengthen the outline till the forms are quite monstrous—the outline of the nose as broad as the bridge of it—still, at a given distance, it goes to nothing; the expression varies every step back you take. But now, take a matting brush, with a film so thin that it is hardly more than dirty water; put it on the back of the glass (so as not to wash up your outline); badger it flat, so as just to dim the glass less than "ground glass" is dimmed;—and you will find your outline look almost the same at each distance. It is the pure light that plays tricks, and it will play them through a pinhole.

And now, finally, let us say that you may do anything you can do in the painting of glass, so long as you do not lay the colour on too thick. The outline-touches should be flat upon the glass, and above all things should not be laid on so wet, or laid on so thick, that the pigment forms into a "drop" at the end of the touch; for this drop, and all pigment that is thick upon the glass like that, will "fry" when it is put into the kiln: that is to say, being so thick, and standing so far from the surface of the glass, it will fire separately from the glass itself and stand as a separate crust above it, and this will perish.

Plate IX. shows the appearance of the bubbles or blisters in a bit of work that has fried, as seen under a microscope of 20 diameters; and if you are inclined to disregard the danger of this defect as seen of its natural size, when it is a mere roughness on the glass, what do you think of it now? You can remove it at once by scraping it with a knife; and indeed, if through accident a touch here and there does fry, it is your only plan to so remove it. All you can scrape off should be scraped off and repainted every time the glass comes from the kiln; and that brings us to the important question of firing.