After the fob is etched, shaped, hammered, and the slit cut in, Ave have next to color and finish it. In coloring copper. Ave can get all the shades of color from light brown to black with a solution of potassium sulphide and water. It is not practical to give exact proportions for this solution, as the sulphide deteriorates with age and exposure to the air. However, the simplest method is the following: In one-half pint of water dissolve a piece of potassium sulphide as large as an ordinary grape. This, when rubbed on the copper, will turn it almost black. If you wish a lighter shade, mix a little of this solution with water, varying the proportions according to the color you wish to get. When it is dry, polish lightly with fine emery cloth, bringing the design out in bright copper color and leaving the background darker, then flow on the fob a thin coating of the banana oil and allow that to dry thoroly, which will take about one hour, and it is ready for the leather strap. If the fob is of brass, use the same method, but instead of potassium sulphide use butter of antimony, full strength. If the fob is . of silver, use the potassium sulphide, but do not use the banana oil.
If you wish to color either the brass or copper verde or green, flow on with a brush the followiing solution:
Copper nitrate ........................ 16 grains
Ammonia chloride..................... 16 grains
Calcium chloride ...................... 16 grains
Water............................... 1 oz.
Allow to dry and finish as before. A quicker method, altho not quite so good, is to mix verdigris with banana oil to the consistency of cream and apply with a brush. When it is dry, rub the design with a cloth soaked in banana oil, which will relieve and bring out the design. Either metal may also be polished bright and finished with the banana oil. See also chap. VI, in which other finishes are described.
Fig. 6. Hat-pins.
For the leather strap, get a piece of leather 5" long and as wide as the slit in the fob. Goat or calf skin will do, but if you wish to do the simple tooling such as is shown on No. 2 and No. 3, Fig. 4, you should use Russian calf skin. Then in the- end that fastens to the fob cut a slit 1/2" long, as shown in the drawing, Fig. 3, and fasten to the fob by the method shown in Nos. 7, 8, 9, Fig. 5. Another way of fastening is shown on No. 1, Fig. 4, which is accomplished as folows: Cut the strip of metal 1/8 wide and twice as long as the strap is wide. Color and finish the same as the fob and pass the strap thru the slit in the fob. Then bend the small strip of metal around the two thicknesses of leather and hammer down the ends. To fasten to the watch cut a slit in the end of the leather as shown, just long enough for the fob to pass thru, and fasten as shown in No. 5.
Pig. 7. Paper-knives.
Hat-pins, Fig. 6, tie-pins, belt-pins, and cuff-links may be made by the same method of etching and finishing as I have described, but with this difference, that before they are colored the pin steins and link backs must be soldered on.
Fig. 8. Paper-knives.
To solder them on is a simple matter after a few trials. First clean with emery cloth the place where the pin is to be soldered and rub on both the back and the pin a few drops of a solution of three parts glycerine and one part muriatic acid; place under the cap that comes on the end of the pin stems a small piece of soft solder3 and hold both over the flame of a gas burner or alcohol lamp and the solder will melt and run, fastening the two together. Then color and finish as before.
The paper-knives, Figs. 7 and 8, are made in very much the same manner as the watch-fob, the only difference being the raising of a slight ridge down the center by laying the metal, design down, on a piece of soft wood and hammering it into shape with the ball end of the hammer. Polish with emery cloth, and hammer lightly and smoothly on a rounding piece of iron. , A railroad spike filed smooth and driven into a block of wood serves very well for this purpose.
3Soft solder is composed of tin and lead in equal parts melted together. See p. 88.
The athletic trophies of etched copper, Figs. 9 and 10, are good illustrations of the extent to which any of the elementary metal-working processes described in this book can be carried. The processes of transferring the design, painting, etching, cleaning, hammering, coloring, and finishing are exactly the same as those described for the making of watch-fobs. The tools and equipment required for the same, with the exception that the dish for etching would, of course, have to be much larger.
In this and the succeeding chapters, the plan is to present, in logical sequence, a series of problems in metalwork, in which, while the processes and tool requirements will be simplified as much as is possible, the chief characteristics of metalwork, namely, rigidity and durability, will in no wise be sacrificed.
Fig. 9. Athletic trophy of etched copper. (The length of this trophy is five feet ten inches.)
Fig. 10. Athletic trophy of etched copper. (The copper plate is nineteen inches high.)