We have now described the simple foot-lathe and chucks adapted for
hand turning, but of the latter a great number may be provided,
and will, in fact, accumulate as the turner proceeds to work upon
objects of varied form and size. No chuck once made should be thrown
away until it has become so reduced, from repeated alterations, as
to be no longer serviceable. And now, before we commence actual
turning, it will be well to offer a few concluding remarks upon the
selection of a lathe. It will be evident from our previous remarks
and illustrations that there is room for great diversity in the size
and quality of this machine, and it is astonishing what excellent
work is often turned out by an experienced hand from a lathe of the
worst description. The simple pole-lathe, which is so out of date
that we did not deem it worthy of notice in this series, with its
reciprocating motion, like the little tool of the watchmaker, has,
before now, supplied the cabinet maker with first-class work, and not
many years since we ourselves stood before just such a clumsy tool,
taking first lessons in the art. Our next step was to a lathe with
wooden poppets, and flywheel of the same material, a mandrel made by
a country blacksmith, which scarcely did even _him_ credit; the value
of the whole, with stand and beechen bed complete, was £2 sterling,
and sufficiently dear at that price. Now, we do not recommend such a
tool, and in the present day a much better may be had at that price,
but, notwithstanding its evident defects, very tolerable work may
be produced from it. We state this to deter the reader from a very
common fault--namely, the purchase of an expensive tool and elaborate
fittings when the purse is shallow, and the skill shallower still. In
fact, any amount may be spent in lathes, and in fitting up a workshop,
but to gain real pleasure and satisfaction from the pursuit of the
mechanical arts, the outlay should not be more than the probable
result in work fairly warrants. A hundred pounds is often expended
in the purchase of a lathe, and a hundred shillings would more than
purchase the work done by it. We speak from our own experience in this
matter, and believe our advice proportionately valuable; and we well
know the satisfaction that ensues when good work has been produced in
spite of the defects in the appliances at command. If the means do
not admit of the purchase of a good lathe necessity must decide the
question, and an inferior one must take its place in the workshop.
Nevertheless, we would rather counsel a certain amount of delay, and
economy and hoarding, that a good foundation may be laid and a lathe
purchased of such average excellence that future additions may convert
it into a really serviceable tool.
It would be invidious and perhaps rather unfair in this little work to
send the reader to any particular lathe-maker. There are several good
and two or three first-class ones in London, and if prices range high,
the work is at any rate of undeniable excellence.
There are also many cheaper firms than those alluded to, where the
work is rather of rough-and-ready style; all depends on what _class_
of work the would-be purchaser proposes to engage in, whether he
intends to confine himself to plain hand-turning in wood, to the
construction of steam engine, and other models of machinery in metal,
or to the more beautiful finished work in hard wood and ivory, which
develop the full power of the machine itself, and the skill of the
accomplished turner. In the former cases, a very plain and inexpensive
lathe will suffice. In the latter, it is absolutely necessary to
purchase one of the best construction, at a tolerably high figure.
The best advice to those of slender means, and who, therefore, vastly
predominate, is to sacrifice all else to the mandrel and collar. The
latter may be bought at from twenty to thirty shillings, ready for
mounting in detached wooden headstocks, and will be far superior to
any that an ordinary smith can produce. In this case, the two poppets
that carry the mandrel and centre screw should be connected together
by a block of wood between them, which latter may be rounded off and
shaped to something near the form of a cast-iron headstock.
The only care necessary in mounting such a mandrel, will be to keep
the axial line parallel to the lathe-bed, and directly over the centre
of the latter. Whether the mandrel is thus a separate purchase, as may
happen from necessity, or obtained as part of the lathe, and fitted in
a cast-iron headstock, it should certainly be hardened, and also the
collar, if of steel. Both will take a higher polish for this process,
and will run easier in consequence. The cost of such a mandrel is
rather greater, because many warp or split in the process, and have
to be thrown aside; and the labour of grinding mandrel and collar
to an exact fit, is considerably increased. The gain, however, is
greater than the loss to the purchaser, and the extra outlay must not,
therefore, be grudged. It is very annoying to find a conical mandrel
worn down by the collar after a twelvemonths' work; for a collar is
thus formed on the conical part, so that it cannot be tightened up by
the back screw.
The first tool to be noticed is the gouge, the form of which is a
longitudinal section of a tube, and is shown in Fig. 41. Of this
tool not less than three sizes should be selected, of the respective
diameters of one inch, half-inch, and a quarter or three-eighths.
When purchased, they require grinding, the bevel being too short. It
is essential that this tool and the turning chisel have a long bevel,
so that the cutting edge should be a very acute angle. (Fig. 41, not
like 42.) It is impossible to do good work with the latter form of
tool which is, nevertheless, of frequent occurrence in the workshops
of amateurs. Both gouge and chisel must be sharpened on an oilstone
(Arkansas or Turkey will be found the best) to a keen edge, _and no
pains must be spared in preserving the tools in this condition_. Three
sizes of chisel to match the gouges should be selected. The latter
tool is not made like that intended for carpenter's use, with the edge
at right angles to the sides, but is sloped like Fig. 43, so as to
present an obtuse angle A, and an acute one B, and the cutting edge
is central, the bevel being alike on both sides, so that the tool may
be turned over, and used with either of the flat sides upwards. The
handles of gouges and chisels should be much longer than those used
by carpenters, and nicely rounded and shaped in the lathe. The most
difficult thing to turn being a cylinder of soft wood; a description
of the method of effecting this will be the best means of initiating
the novice in the art of turning. In all the most perfect work by
practised hands, there is a sharpness of edges and roundness of
mouldings, that are exceedingly agreeable to the eye, and bespeak
at once keenness in the tool with which the work has been done,
and steadiness in the hand of the operator. The novice must aim at
similar perfection, and to this end he must determine to avoid the
use of sand-paper, and trust to his management of exceedingly keen
tools to put a workmanlike finish to his work. To commence with the
proposed cylinder. Let a piece of sound beech be selected for the
first essay, as being less difficult to manage than deal, the grain
of the latter tearing up in long shreds under the action of the tool.
The first thing to be done, after sawing off the necessary quantity
of sufficient diameter for the proposed work, is to round it off
roughly by means of the hatchet and draw-knife, or spoke-shave. The
next thing is to mount it in the lathe. For this purpose the prong
chuck, or, better still, that represented as an improvement on the
latter, and shown in Fig. 23B, must be screwed on the mandrel, and
the work made secure by the aid of the back poppet centre. Care should
be taken that the piece runs truly between the points of support, and
that it revolves steadily without shake. There is no real necessity
for using the compasses, or other contrivance for finding the exact
centre at each end, as sometimes recommended, neither, indeed, is it
always possible thus to find the axial line. It is easy to fix it at
first lightly in its place, and ascertain by a turn or two of the
mandrel, how nearly it runs as it ought to do. If it seems tolerably
true, a turn of the back centre fixes it securely, if not, it can be
shifted in any direction at pleasure. The tyro ought, however, to
be warned that he is likely to be deceived in the size of the rough
piece, and that he may very probably think it of sufficient diameter
for the proposed work when in reality it is too small. Practice, or
the use of the callipers, which are bow-legged compasses for measuring
the diameters of work, will soon settle the question. The piece being
properly fixed in the lathe, the latter is to be set in motion by
means of the treadle, the rest having been first fixed as near as
possible without touching the piece, and the T clamped parallel to it.
If the tyro wishes to become a proficient, no pains must be spared
to acquire the knack of working the treadle without moving the body
to-and-fro. He must learn, therefore, to stand firmly on one leg, and
after the wheel has been put in motion, he must let it and the treadle
have its own way. He will thus soon _feel_ when the crank has passed
the dead point at the highest point of revolution, and the proper
moment to bear down with the foot. It is not necessary to describe the
precise movement, as a few trials will teach the method much better
than any written description. At first it is hard work, and constant
change of leg from the right to the left, and back again, will have to
be resorted to to diminish the fatigue. Practice will, however, remove
all difficulties, and allow the whole undivided attention to be given
to the management of the tool.
[Illustration: FIG. 41.]
[Illustration: FIG. 42.]
[Illustration: FIG. 43.]
The gouge must be held down firmly on the rest with the hollow side
upwards, and the bevel of the edge forming a tangent to the work, Fig.
44. In this position it will cut freely and smoothly, and the edge
will be preserved. If held horizontally, as in Fig. 45, it is evident
that the fine edge of the tool will be immediately destroyed by the
rapid blows it will receive as the rough wood revolves in contact with
it. Its tendency in the latter position will be to scrape, instead of
cutting, and the fibres of the wood will thus be torn out in threads,
and the surface of the work be roughened. The gouge, then, being
placed in the former tangential position, the right hand grasping the
handle, the left the blade, as in Fig. 46, the tool is to be slowly
slid along the rest, and a series of light shavings, more or less
continuous, will be removed from end to end of the piece. Let the
workman bear in mind that the tool is to take a firm bearing on the
rest, and that it must not move to-and-fro with the inequalities of
the piece to be turned. It is not necessary to remove large chips
unless the turner has acquired from practice perfect command over the
tools, and for the adept this chapter is not written. After the most
prominent inequalities have been removed, the _side_ of the gouge will
come into use instead of the extreme end, and with this the work may
be rapidly reduced to its intended size, always allowing, however,
for the final cut with the chisel. Before the latter is taken up,
the piece of work is to be rendered as level and true as can be done
by the aid of the gouge alone; indeed, if the latter is of tolerable
size, and skilfully used, a finish can be put upon the work by it
almost equal to that which the chisel can produce and if the work
in hand were a moulded pattern, with hollows and raised work, great
part would have to depend on the gouge alone. In the present case the
chisel must be used, and the method is as follows: Take a hold with
both hands, as directed for the management of the gouge, but instead
of the flat part lying evenly on the rest, the tool must be partly
raised from it, so that only the lower edge takes a firm bearing.
By this means the upper angle of the cutting edge (_generally_ the
most acute) is kept clear of the wood, and the latter is cut away
only by means of the middle and lower part of the edge, as shown in
Fig. 47. If placed as in Fig. 48, the acute angle, _a_, is sure to
catch and stick into the work, spoiling in two seconds all that has
been done. The chisel can be used with either of its flat sides
upwards, and moved along the rest from right to left, or from left to
right, or turned upside down, as Fig. 49, so that the acute angle is
downwards. These positions are shown in the Figs. 47 to 51. The only
care necessary is to keep the upper point clear, allow the chisel to
rest as flatly on the wood as the above precaution will permit, and to
take as _fine_ and _continuous_ shavings as possible. The chisel will
be found to draw itself along in some degree as the cut proceeds, and
when this action is felt, it is doing its work properly--still, it is
a difficult thing to use a chisel well, and the tyro will fail many
times and oft before he will succeed.
[Illustration: FIG. 44.]
[Illustration: FIG. 45.]
[Illustration: FIG. 46.]
[Illustration: FIG. 47.]
[Illustration: FIG. 48.]
[Illustration: FIG. 49.]
[Illustration: FIG. 50.]
[Illustration: FIG. 51.]
The chances are that this initiatory lesson will result in anything
but a correct cylinder--the surface will not be true like a ruler,
but if tried by a straight edge it will be seen to be wavy. Tested by
the callipers, Fig. 52, one part will be larger than another, even if
the extreme portions be tolerably true to the proposed gauge. Now,
the best turner on earth found just these difficulties, and nothing
but perseverance and resolute determination will overcome them.
Never mind spoiling the first piece of work, give up making it of a
determined size, but do not give up making it a true cylinder. Keep
the callipers at work, and gently level the prominent parts (you must
work down to the size of the deepest hollow, for you cannot fill up
such valleys like a railway engineer; you must throw down the adjacent
hills instead), proceed gently, little by little; make the tool obey
you, show it (as Ruskin speaks of pencil and brush) that you will
not yield to its caprices and "henceforward it will be your most
obedient servant." Having done the best you can with the surface of
your cylinder, proceed to square up the ends, and mind the angle at
this part is a right angle, _square_ and _sharp_, not rounded off. Now
this again requires care and a knowledge of the proper method. You
will work chiefly with the lower corner of the chisel, and we shall
best describe the management of the tool by supposing the cylinder
an inch too long, and that the extra piece is to be removed. Now
there are three positions in which the chisel can be placed to bring
its lower corner in contact with the cylinder. First, with the blade
perpendicular to the work; secondly, with the blade inclined to the
left, Fig. 53, as if to round off the end of the piece; thirdly,
inclined to the right, Fig. 54. Held perpendicularly it will cut a
fine line, but penetrate slightly; alternately in the other positions
it will remove a V-shaped piece, and thus the cutting off is to be
begun. One side of the cutting, however, has to be perpendicular, the
other may be as sloping as convenient. Now, it is to be remembered in
cutting the upright side, which is the end of the roller, the chisel
is to incline _rather to the right_, for this reason,--if it incline
to the left a momentary inattention will cause it to take the path
_a, b_, Fig. 55, the tendency being to cut a spiral track towards
the left. The experiment may be made by gently resting the edge thus
inclined on any part of the roller, when it will describe a spiral
at once. To the right, then, the chisel must _slightly_ incline, and
it will cut off a thin curling shaving like Fig. 56, leaving the end
of the piece quite smooth and shining. When the piece is nearly cut
off, great care and lightness of hand must be used, as the central
portion will have become weak and ready to break off before the work
is finished. When it will no longer bear the chisel, take it out of
the lathe, break it off, and neatly finish with the sharp chisel the
central portion, and your first lesson is learnt. There is certainly
very little of interest in turning an imperfect cylinder, for it is
useless when done, but the alphabet of the art, though not amusing,
must be first thoroughly mastered, and the rest will follow in due
course. If, however, the work seem unreasonably dull and stupid,
the cylinder may be converted into a tool handle, which will be at
any rate a useful article, besides affording practice. No special
directions are needed in addition to the above, except in respect to
the ferrule. This is to be cut off a piece of brass tubing or an old
gun barrel, or it may be had at the tool shops ready cut to any size.
Begin by turning down the place for this ferrule, taking care not to
cut it too small or the ferrule will drop off. Take the piece out of
the lathe, and with a mallet hammer on the ferrule. Return it again,
taking care to centre it in the old marks, and finish the handle. The
brass or iron may be polished with a file for this first attempt.
[Illustration: FIG. 52.]
[Illustration: FIG. 53.]
[Illustration: FIG. 54.]
[Illustration: FIG. 55.]
[Illustration: FIG. 56.]