Copper Work: A Text Book for Teachers and Students in the Manual Arts

Chapter IX.

Chapter 111,028 wordsPublic domain

SPOONS, SUGAR TONGS AND TEA SCOOPS.

These exercises are easily carried out after a little experience. No steps are taken that have not already been described, except in the case of forming the bowl of the spoon. This is done by taking a piece of lead and making a depression in it the size and shape of the bowl required. A piece of hard wood is shaped on the end grain to fit the depression made in the lead. The metal is placed over the depression and the wood shape placed on top of the metal; it is then driven into the form by using a hammer. This will give the general shape of the bowl which may be trued up later by sawing and filing.

RIVETS.

The making of rivets is quite important as it is impossible to find in the market the variety in size and shape of head that each piece of work demands. Where rivets with a wire 1/8" or less are needed, they may be made as follows: Take a piece of iron or steel A, Plate 50, thicker than the desired length of the rivet and drill a hole through it having its diameter a little greater than the wire of the rivet. Take a piece of copper wire of the required diameter and about 1/8" longer than the thickness of the iron. Place the wire in the hole and the iron on some smooth metal surface, B. With a hammer make a burr of the wire that projects above the iron. Then reverse the iron and drive out the rivets. This gives what is shown at D. The rivet is then cut off the required length, placed in position and headed up. The head may be made conical, I, hemispherical, J, pyramidal, K, or square, L, in shape. It may be headed up simply with the hammer, or with a rivet header, M.

When necessary, the process may be reversed and the head made first; but when made in this way, a rivet block is needed to rest the head in while making the burr.

The rivet may be made more of a decorative feature by sawing out of sheet metal some suitable design as shown at P, Q, R. Drill a hole in the center the size of the rivet and then use any ordinary rivet head. Nails may be made by the same process, headed and pointed as at S and O.

TO DRAW WIRE AND SMALL TUBING.

Cut a piece of copper the length required, having the width about three times the diameter of the tube that is to be made. The edges must first be made parallel by filing. In a block of maple or some hard wood, with a wood file, make a groove as shown at Figure 30. Place the strip of metal over the groove and, with a somewhat pointed hammer, drive the metal into it until it takes the shape of a V. Figure 31 A. Then place it on the flat part of the block and strike on the edges with the hammer, turning them in until they meet, as at B and C.

A draw plate is then placed in the vise, Figure 32. After pointing the tube a little, the end is placed in one of the larger holes and drawn through. This will bring it somewhat into shape. Repeat this operation by drawing the tube through the hole the next smaller in size and so on till the tube is of the diameter required.

Wire may be drawn in the same way. Rectangular, triangular and square drawplates may be obtained as well as circular ones.

POLISHING.

To polish work, a cloth or felt buff is placed on a lathe or a polishing head. With a little cut-quick and rouge objects may be brightened by holding them against the wheel.

STAMPING WORK.

The marking of work so that it will be known to whom it belongs and doing it in a neat and workmanlike manner is sometimes a problem. Using a gummed label with the name written on it has been tried, but the labels frequently come off. The name has been scratched with a sharp-pointed tool, but it is not an easy thing to do and certainly does not look well. The way described below however has proved very satisfactory. Have each pupil design a little trade mark of his own, and work it out on the end of a piece of tool steel, 1/8 inch or 3/16 inch square, round or hexagonal. This can be done by a little filing, perhaps the use of a drill if the design should call for it, and a little emery paper to take off all sharp edges. This serves as a stamp with which he may mark all of his work. The instructor has a book with the names of the pupils, and after each name he may stamp this mark and thereby register it so that he may tell at any time to whom work belongs.

Figure 33 shows a stamp and a few suitable designs.

COLORING.

The most satisfactory color that can be given copper is a bronze which comes naturally if left to come in contact with varying atmospheres. If the object has a good polished surface in the first place the color seems to become richer as time goes on.

A color that is satisfactory in many cases is obtained in the following way:

Place in a porcelain dish and bring to a boiling heat, liver of sulphur, 1 oz., and water, 1 qt. Dip the object to be colored in this solution while hot and then rinse in clean water. This gives the object a very dark color. Take a little powdered pumice stone on a piece of cloth and rub over the surface lightly bringing the copper color to the surface where desired.

A greenish color is given copper by submitting the object to the fumes of spirits of ammonia.

Beautiful colors are obtained by heating the object to different degrees, over a gas plate, but these results are not permanent.