F. W. Putnam, Instructor Manual Training School, Lowell, Mass.

First class lathes are now made by a number of concerns, and sold at very low prices, yet are not within the means of every amateur who might wish to own one. The May number of "Amateur Work" contained a very good article on the making of a modern turning lathe frame. This frame can be made at a small cost and, when fitted with a suitable lathe set, will serve admirably for the turning of exercises which follow.

Among the many excellent smaller wood lathes now in the market is the lathe shown in Fig. 3, made by the Washburn Shops of the Worcester Polytechnic Institute, Worcester, Mass. As all modern lathes are practically alike in general construction, let us examine Fig. 3, and learn some thing of the parts of a lathe.

Every lathe has four principal parts: - the shears, the head-stock, the tail-stock, and the rest. The head-stock is stationary, while the tail-stock and the rest are movable along the shears, and may be fastened temporarily at any desired place by means of clamps. The office of the shears or ways is to support the head-stock and the tail-stock in such a position that the axes of their spindles will be in the same straight line, in whatever position on the shears the tail-stock may be fastened. The end of the shears is shown at D, Fig. 3. The shears include the legs E. Sometimes lathes are mounted on wooden benches, and are then known as bench lathes, in which case the legs are very short. The shears have generally two parallel grooves or tracks cut in on or the top surface, in the direction of the line of centres of head-stock and tail-stock. These grooves are V-shaped, corresponding exactly to bosses which project from the under side of the head-stock, tail-stock and the rest. The head-stock, shown at A, Fig. 3, is fastened rigidly to one end of the shears. Fig. 4 shows a longitudinal section through the head-stock.

The live spindle is shown at K, Fig. 4, to which the cone pulley L is fastened. The live spindle is used to revolve the stock which is to be turned. A driving belt passes over the cone pulley from a counter F, Fig. 3, placed above the lathe, the belt thus turning the spindle to which the cone pulley is fastened. A fork or live centre is placed in the end of the spindle, and one end of the stock that is being turned is driven into this fork and revolves with the spindle. The spindle turns in bearings or boxes shown at M, Fig. 4. This lathe has self-oiling boxes, but generally small oil holes are drilled through the top cap of each box, through which oil is supplied to the rubbing surfaces. A few drops of oil should always be put into each oil hole when the lathe is first started. Removable caps or plugs are generally used to keep dust out of the oil holes.

Fig. 3.

Fig. 4.

Fig. 5.

Fig. 6.

Fig. 7.

Fig. 8.

Fig. 9.

Fig. 10.

The live spindle is usually made hollow, with a tapered hole, N, at one end. into which the live centre, which is cut to a corresponding taper, is placed. The live centre can be removed from the spindle by a smart rap from an iron rod passed through the back end of the spindle which is generally hollow. After continued use the spin-dle may move back and forth somewhat, giving what is known as "end movement." An adjusting screw or collar, O, will prevent this. The screw thread shown at end of the spindle at P, Fig. 4. is used for the attachment of face plates shown at H and J, Fig. 3.

The tail stock, shown at B, Fig. 3,,and in section in Fig. 5, supports the tail spindle. The tail spin-dle holds the dead centre, so called because it does not revolve, as does the head centre. The stock to be turned revolves between this dead centre and the head centre of the head stock.

The tail stock may be fixed in any desired position on the shears by means of a clamp. The spin-dle B, Fig. 5, may be forced out from, or drawn back into, the tail stock by means of the screw thread on the shaft, C, Fig. 5. This screw thread on the shaft C, which fits exactly a tapped hole in the tail spindle, takes up the space E, Fig. 5. The hand wheel, D, is used for this movement of the psindle. The spindle can be clamped so as to prevent further movement by a clamp handle, shown just above the letter B, Fig. 3. If the handle, D, be turned until the back end of the dead centre, A, Fig. 5, strikes the front end of the screw on shaft, C, the dead centre will be loosened in the spindle, and may then be taken out. An oil hole, F, is used for oiling the shaft, C.

The rest, shown in Fig. 6, supports and assists in guiding the cutting tool. The casting, A, is adjustable along the shears in the same manner as the tail stock; being fastened, together with the tee holder, C, in any desired position by means of the clamp handle, B. As can be seen from Fig. 6, the tee holder, C, can be moved in any direction desired, and as the tee, G, Fig. 3, is movable in the tee holder, the rest has practically universal adjustment. The distance of the tee from the work is thus regulated, and its height and angle with the stock to be turned are regulated by the set-screw which fits into the tapped hole at D, Fig. 5. Fig. 7 shows two views of a fork centre, or head centre,-and.Fig. 8 shows two views of a cup centre, or tail centre.

The head centre is used in the live spindle to make the work revolve, one end of the wood being driven onto this head centre by a mallet, the tail centre being brought up against the other end. This tail centre is held in the spindle of the tail stock, and as this spindle does not revolve, the tail centre is often spoken of as the dead centre. Fig. 5 shows that the end of the tail spindle has a tapered hole to fit the taper of the tail centre.

Fig. 9 shows one form of a face plate. This is-used when the stock to be turned cannot be held between centres. At one end it is tapped out to fit the thread at the end of the live spindle, P, Fig. 4. It is used in turning cups, balls, and such hollow pieces as require that turning tools be used on one end. Generally this class of work is not-fastened directly to this face plate, but is held in a block of wood, or disc, fastened to the face plate by wooden screws, and hollowed out so as to hold the work. This wooden disc is called a chuck. The face plates are of various sizes to accommodate different classes of work.

The size of a lathe is determined by two tilings, the swing, and the length of the shears. The swing of a lathe is twice the distance from the centre of the spur of the live centre to the nearest point of the shears. For instance, a lathe is advertised as having an 11" swing and a 4" bed. Nothing over 11" in diameter could be turned on such a lathe, while the greatest distance obtainable between centres would probably be not over 27".