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Wood-Turning

( Originally Published 1937 )



Now that many small wood-working machines are on the market the craftsman will want to know something about their use. In general, machines can be classified into two groups: (a) Those which do things impossible by hand and hence introduce to the craftsman a new art—lathes in particular; (b) Those which merely do things more quickly or easily than the craftsman can by hand.

Machines of the latter sort have two effects : (1) They make it possible for the craftsman to do more work in a given amount of time, and hence produce more cheaply; (2) They make it possible for him to do tolerably passable work with less skill, and so contribute to the general decline of good craftsman-ship. Also, these machines offer serious hazard to inexperienced (experienced, too) people using them. The accident reports of medical men and insurance companies will show a rapid increase in injuries to hands and fingers from mechanical saws, planers, jointers, and shapers. Yet we are going to see a great deal of these small machines because of their relative cheapness and convenience. It is too bad, in a way. We could stand the increased output of cheap furniture, and the inevitable revival of jig-sawed, ginger-bread ornament, as well as the decline of craftsman-ship, but it is distressing to think of the beautiful fingers that are to be mangled and amputated.

As the makers of these machines supply full instructions for their use and care, I confine this section to information needed by the craftsman in selecting machines and deciding which he requires for his work.

If craftsmanship is not to suffer extinction from the loss of texture inevitable when hand work is displaced by machine work, we must compensate for the loss by achieving a greater distinction of form. And I mean literally, that we must spend over the drawing board the time we have saved from our hand labor. Our work, having no skill of hand nor richness of texture, will amount to nothing if it has not fine proportion and subtle grace.

Circular Saws

The chief advantage of circular saws is that they cut so finely that, finishing with the plane is unnecessary. Be certain that the spindle runs perfectly true, and that there is not the slightest oscillation of the blade. Spin the shaft by hand, holding a pencil point to the side of the blade to test it. The machine should have an arrangement to tilt the saw to 45°, keeping the table level. It should have adequate provision for guarding the blade; most of the guards are regarded as a nuisance and not used: during such times accidents occur. Circular saws should never be used in classes of young children.

Jig Saws and Band Saws

These are useful for roughing out stuff to be turned on the lathe, and for cutting curved brackets, sections of chair backs and the like; also for ordinary ripping and cross-cutting, although less accurate for this than a circular saw. Jig saws are much less dangerous than either circular or band saws, and will do anything a band saw can do on wood of moderate thickness as well as things a band saw cannot do—such as cutting out the inside of pierced patterns on boards. But it is a slower and less sturdy machine than the other. For cutting over 1 3/4" thick, small jig saws are unsuitable. Do not leave curved surfaces as they come from the saw. Always work them over with the spoke shave, files and sandpaper until the lines of the saw disappear. Neither allow yourself to be seduced by the ease of cutting into a fondness for over-elaborate scroll work. It is unlikely that such can ever be valuable to the design as it is not structurally necessary, adds nothing to the craftsmanship of the piece, and is seldom beautiful in itself.

Belt and Disc Sanders

A combined belt and disc sander is useful for smoothing, especially on rough end-grain and cross-grained wood that is difficult to plane. Since its potential danger is practically limited to "skinning" the fingers or knuckles, it is much preferable to a jointer-planer, for everything except actual jointing. It smooths wide surfaces, and can be used for truing up mitre-cuts, the corners of boxes, drawers, etc.

Jointer-Planers

A jointer that will plane the face of a board up to 6" wide offers some interest to the craftsman, but since it has no provision for sizing boards to a certain thickness, as a real planer has, its value will be chiefly for jointing (truing the edge for gluing). Unless you have a good deal of this to do I should not advise buying one of these dangerous machines. If you are buying finished lumber you can have it jointed at the mill. If you are trimming it with your circular saw it should leave the saw with a perfect edge anyway.

Drill Presses

A drill press approaches the classification of machines that do things impossible to do by hand, since it is almost impossible to drill by hand a hole that is absolutely perpendicular to the surface. It is not a dangerous machine. Doing accurate work, it also saves a great deal of time, especially in drilling iron and steel. It is worthwhile to get a powerful one, otherwise a hand-powered blacksmith's drill is better. It is no trouble to drill 1/2" holes through cast iron with a blacksmith's drill.

Shapers

A shaper is useful for running a large quantity of special mouldings. It is simpler and more fun to make small quantities with hand moulding-planes. As shaper knives cannot be reground by the amateur craftsman, he should insist on getting high speed steel rather than carbon steel knives. They stay sharp much longer. The knives should exactly match in thickness and diameter else they cannot be locked to the shaft securely, and are liable to fly out. Some circular saws have provision for use as shapers. As many accidents happen with shapers they should be used with great caution.

WOOD-TURNING

THE LATHE 1S a fascinating instrument that bears the same relation to wood as the potter's wheel does to clay. There is the same magic about it—that feeling of encountering a new dimension. Or perhaps it is the curious feeling you get from working with something that is obviously of three dimensions, yet in which you have command over only two: length, measured on the axis of rotation, and diameter, measured at right-angles to it.

The possessor of a lathe has it in his power to make out of wood all manner of round things; bowls, lamps, chair and table legs, potato mashers, carving mallets, candlesticks, breadboards, cake-trays, nap-kin rings and tea-pot stands. Wood bowls are ideal for salads, fruits and nuts. Old fashioned wooden trenchers and cups suit the country house perfectly.

The main requirement of a lathe is a shaft that runs true, and a bed that is heavy and solid. Many small lathes are deficient in this respect. The beds are light and the lathes develop vibration, making it difficult to do clean, accurate work. For heavy work of large diameter, investigate the market in used machiery. Heavy, full size lathes can often be purchased for less than the small models. For small work, the bench lathes, scrutinized for points mentioned do very well. See that your lathe has at least three speeds, a full outfit of face plates, tool rests and centers, and chucks for both headstock and tail-stock. Mount it securely in a well-lighted situation.

TURNING BETWEEN CENTERS

Long things such as table or chair legs, and the stems of lamps or candlesticks are turned between centers. Cut the wood off longer than your finished work is to be—say about two inches. Find the centre* of each end by drawing the diagonals from corner to corner. Remove the live center from the spindle, set the point of it on the centre of the end of your wood and give it a sharp blow with a wooden mallet (never a steel hammer) until it engages firmly with the wood. Replace the center on or in the spindle, and fit the tailstock to the other end of the wood. The tailstock is clamped to the bed in its approximate position, and the dead center advanced into the centre of the wood. When you have made a fairly deep impression in the wood with the dead center, withdraw it and put a little soap or wax into the space. Then screw the center up and lock it. In doing this get the habit of feeling the headstock pulleys with the left hand while you screw up the tailstock with the right, until you feel a slight resistance to the movement of the spindle. If the resistance is too great the spindle will not turn; if too little the work may vibrate.

Set the edge of the tool rest just below the centre line and close to the wood, without interfering with its free rotation. Form the habit of giving the pulleys a spin with the left hand before starting the machine to be sure that everything is ready.

Start the work on slow speed unless it is small. Use a heavy round-nosed gouge for the first roughing and hold it firmly against the rest with one hand while the other grips it well toward the end of the handle. In all stages of turning keep a very firm grip on the tool and have it braced steadily. Accidents invariably happen because the worker has lapsed his attention for a moment, relaxing his grip on the tool, gesturing with it toward the work, forgetting that it is revolving at terrific speed, or neglecting to see that everything is right before starting the motor.

Start at one end and pass right along to the other, taking off an even cut all the way. Repeat, readjusting the rest as necessary until the wood is a rough cylinder. Then increase the speed, finish it further with a round-nosed flat chisel. The chisels should be kept extremely sharp with a fine oil stone and leather strop. Poor work will always result if you substitute sandpaper for keen edges.

Set off the longitudinal measurements with a pencil on the smooth surface you have just finished, then hold your pencil still, on the rest, and revolve the spindle by hand to mark the lines all around the wood. Now, turn out the rest of the wood to your lines, following the curves of the drawing from which you are working, using the chisels that seem best adapted to each curve. Use the calipers frequently to check diameters.

If you have a "tapered chuck," a solid socket that fits on the spindle, you may turn the hole in a napkin ring, or the socket in the stem of a candlestick, thus: turn the waste wood on the base of the stem to fit the socket. Remove the work and drive it tightly into the socket. Put the chuck on the spindle, and set a lathe bit of the right size (a straight-shank wood bit made for boring on the lathe) into the tailstock chuck. Screw the tailstock chuck up until the hole is cut the required depth.

If you have no tailstock chuck, draw the tailstock away and put the tool rest across the end of your work at right angles to its axis. With a narrow, flat chisel turn the hole out. Then bring the tailstock into position again to steady work for further turning.

The holes for wiring may be bored in lamp stems with a long bit and the tailstock. They may also be bored in the rough wood before turning with an ordinary brace and bit. Bore from each end to meet in the middle. If the bit is not quite long enough burn the wood out with a red hot iron rod. For long stems of floor or table lamps make the stem out of two pieces of wood, rabbetted down the middle and glued together.

TURNING ON A FACE PLATE

Bowls, breadboards, bases of lamps, and candle-sticks are turned on faceplates. Plane smooth the side of the wood that is to be the bottom, and on it draw a circle 1/4" larger in diameter than the finished size calls for. Saw this out and screw to a face plate with short, heavy screws.

Put the face plate on the spindle and set the tool rest across the wood at right angles to the axis. Take a heavy fiat chisel and, with slow or medium speed, true up the edge by pressing the chisel against it at right angles to the face of the wood. It is also possible to true the edge from the side position as in turning between centers, but it requires greater care to avoid the danger of splitting off pieces. Next, true up the face of the disc of the wood.

Increase the speed, and shape the wood to follow the drawing, using rule, pencil and calipers. Bore the hole in lamp bases to receive the stem with the tailstock bit, or with a flat chisel. If the hole is deep take care to keep the chisel level and hold firmly. It should be a strong chisel with a long handle. The stem should have its end turned to a kind of dowel to fit this hole. A shoulder is left on the solid part of the stem to support it.

Glue the parts together while the base is still on the lathe. Then turn the dead center up into its place to ensure the perfect alignment of the stem. When the glue is dry touch up the work if necessary, use fine sandpaper, and apply the finishing materials (see page 55) while it revolves at slow speed.

Turn bowls first with the bottom outwards. Finish the outside, mark the bottom with an outline for the face plate. Then put the face plate on the bottom. Turn out the inside and touch up the outside. Bowls, without a "foot" or rim, can be turned directly with the face plate on the bottom from the first.



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