The Young Mechanic / Containing directions for the use of all kinds of tools, and for the construction of steam engines and mechanical models, including the art of turning in wood and metal

by James Lukin

You will certainly find a difficulty in turning all exactly alike the little pillars of these baskets. You should turn several at once out of the same piece, separating them afterwards. Thus your pattern will always be close to the half-executed copy, which will somewhat assist you. Do your best in this respect, but be specially careful, at any rate, to make all exactly the same length. One pillar is shown separate, but you can design a pattern for yourself.

Begin by turning a long cylinder; then set off the respective lengths of the pillars. Turn one complete as a pattern, and set the callipers to the largest part of it. Then go to work upon a second, using callipers freely at all parts of it. As these pillars will all be slender, you will be in great danger of breaking them; therefore use your tools lightly, taking only a very slight cut. But with all your care you will find it difficult to turn a row of more than two or three of the size wanted for such little baskets. I shall therefore show you how to make a support to fit at the back of the bar you are at work upon to support it against the pressure of the tool.

Fig. 50 gives a representation of one or two such supports, which are often required in turning. The first is the most simple, and is the one most generally in use, because easy to make and to apply, and it answers tolerably well. A is merely a piece of wood, about three-quarters of an inch thick, cut as shown. This is stood up between the lathe-beds, like C, and fastened with a wedge before and behind. It allows the work in the lathe to revolve in the notch which is cut in it, as is evident from the drawing. One, two, or more such may be used if necessary. They must be carefully adjusted, so as not to bend the piece which is to be turned, and which is to be just supported, but no more. Where the back-stay, as this contrivance is called, comes in contact with the work, the latter is to be left of the size it was when this was adjusted to it as long as possible. It must then be shifted a little, and that part which formerly rested against it finished.

B is another simple form of back-stay, capable of nicer adjustment. The foot is that of a common rest, but if you have not a spare one, any wooden support is quite as good. Into this fits a turned part of the upright x y,—the upper part, y, of this being planed flat. Neither should be of deal; ash or elm is preferable. Thus the part x y can be raised and lowered at pleasure in the rest-socket. The top part is made of a half-inch board, about 2 or 2½ inches wide; a slit is cut in it, and it is fastened to x y by a short bolt and nut. Thus it is easy to raise and lower the end of this part, and to put it nearer to, or farther from, the work in the lathe, against which it can be adjusted with great nicety. Although there are several forms of back-stay, of more or less complicated construction, I know of none more generally serviceable than this last, which the young mechanic can make for himself. The notch should be lubricated with soap, or, if the blackness is not of importance (as when this part, which rotates in the notch, has finally to be cut away), with a mixture of soap and blacklead. This, remember, is always to be applied to wooden surfaces that are to work easily upon each other.

It will sometimes happen that you require to bore a hole through a long piece of wood, as would be the case in making a wooden pipe, flute, bodkin-case, and many similar articles. To hold these in a chuck only would be often impossible, because the hole in the chuck would have to be as deep at least as half the length of the piece to be bored.

For this kind of work, therefore, and for turning up a point on the end of a cylinder of iron or steel, like that of your back poppit, the following contrivance is used, which is called a boring-collar or cone-plate. It is represented in Fig. 50, D and E. This consists of a circular plate of metal, three-quarters of an inch thick, turning upon a large screw or pivot at its centre, by which pivot it is attached to a short poppit head, fitting between the bearers of the lathe as usual. There are six or eight conical holes bored round the circular plate, each of a different size; and these are so arranged as to height, or distance from the centre, that the top one (being in a perpendicular line passing through its centre and that of the bolt) is exactly as high as the axis of the mandrel. Thus, if it is clamped in that position, with the largest side of the conical holes next the mandrel, a piece of wood might be held at one end in a chuck, while the other might rest in such hole as was best suited to its size, not actually passing through it, but resting in the inside of the conical hole, in which it would rotate almost as freely and as truly as if it were supported by the ordinary point of the back poppit.

Sometimes it may be preferred to allow the end of such a piece of work to project through the cone-plate, a collar being turned on it to prevent it from going too far. A tool-handle, for instance, of the pattern before given, may be beautifully bored in the lathe by allowing the ferule to rotate in one of the holes of the cone-plate, the shoulder behind preventing it from going too far. The rest is brought round in front of the end of the handle, and a hole bored by a drill for wood; or, the point of a drill is brought against it, while the other end (having had a slight hole made by a centre-punch for the purpose) is allowed to centre itself on the point of the back poppit. The screw of the latter is then advanced, and the drill being prevented from itself revolving either by being grasped by the hand or a vice, a beautifully straight and even hole is rapidly made.

Fig. 50, F, shows the position of the various pieces. The drill is here kept from rotating by a small spanner, the handle of which comes against the bed of the lathe. A great deal of work, both in wood and metal, is always drilled in this way.

For wood, a small nose-bit, or auger-bit, or one of the American twist-drills, can be used, and this may be succeeded by a larger, until the hole will allow of the introduction of a finishing-tool of some kind, held in the hand. Of course the latter is not necessary in boring out handles for the tang of a tool, but only in turning boxes for pencils, needles, or other articles, which require to be neatly finished inside as well as out; all these are to be bored before the work is cut free from the superfluous wood out of which it was turned. You can even use the cross-chuck for this work.