Seeing that the Editor of the above Articles has illustrated and
described Holtzapffel and Co.'s Rose Cutter and two methods of
executing rose cutting, the latter being the ordinary rose engine, I
am induced to send you a description of a method that I have adopted
whereby I can with considerable despatch execute this description of
turning.
I will first preface my description by saying some thirty years ago
I purchased Ibbetson's Book on eccentric turning, and I was so much
taken with it and the illustrations, that I determined to make myself
in accordance with his description and engravings an eccentric chuck;
and although I was a long time about it, being at the time much
otherwise engaged, I succeeded beyond my expectations, and was enabled
to do some very fine work with it; and I have never regretted the time
I spent over the chuck, as I became familiar with metal turning and
screw cutting _flying_ in the lathe, which latter I was surprised to
find how easily I could execute. However, I was much disappointed in
the usefulness of the chuck (Holtzapffel's eccentric cutter, which I
purchased is far more useful), and also with the tediousness of using
it (fancy stopping the lathe to alter the chuck 360 times or 180 times
to cut a row of circles either distinct or overlaying each other),
and there was also a certain vibration occasioned in using the chuck
which I also disliked. I therefore determined to cut up some rosettes
and convert my headstock into a rose engine, to effect which object
I got Holtzapffel and Co. to return up with a new steel collar and
make my mandrel traversing. I cut myself a rosette both ways with
16 waves, and I was much pleased with the variety of work I could
perform with this one, but the rosette took me a long time to make,
and disheartened me from cutting up a variety. It, however, occurred
to me that if I added an extra mandrel by the side of and attached to
my headstock, and on which extra mandrel, if I had an eccentric chuck
connected with a rod to the wall of my room, I could get my headstock
to oscillate, and by connecting and multiplying wheels cause as many
waves on each revolution of my principal mandrel I pleased; this after
much time and patience I succeeded in doing, and worked it with the
hand motion often adopted for rose work. After between two and three
years, I put the extra mandrel over my principal mandrel instead of by
the side as before, to enable me to dispense with the hand motion and
to work the upper mandrel with the slow motion on my lathe wheel, and
which I found a very great improvement, and I now give the details of
the plan I have adopted for the benefit of your numerous readers.
The drawings are to a two-inch scale, or one sixth of their full size.
Fig. 400 is a side view of my headstock (part in section) with the
upper mandrel, A, added, showing the connection by an intermediate
spindle, B, with the large cog wheel, C, on my lower mandrel, D, and
other additions.
The back centre, E, of my headstock is connected with the back screw,
F, and drawn out or pushed in with it, and is fixed by the set screw,
G. When drawn out the steel screw, H, at the end of the mandrel, D,
removes to receive the screw guides which are then fastened by it, and
the piece, I, with segments of a thread to match the guides, is slid
up by a wedge to the guides and then fastened by the screw J, I, can
also fix some roses cut on the side, and other apparatus with this
screw H.[27]
[27] It is not a good plan to make the point, E, movable. It would
be better to slip the guides or rosettes over it: and generally to
arrange this part as usual with a traversing mandrel, P, H.
The large cog wheel, C, is screwed up with the screw, K, to the
mandrel pulley, L. On the front of the pulley is the division plate as
usual.
The intermediate adjustable spindle, B, is carried in a frame shown
separately by Fig. 405; it is allowed to rise or fall as may be
required for the wheel, M, to gear with the great wheel, C; provision
being also made for an intermediate wheel, N, (see Fig. 403) to
connect the wheel, O, with the wheel, P, on the upper mandrel when
required.
The eccentric chuck is fixed on screw Q of the upper mandrel.
Fig. 401 is a plan of the mould for the back cast-iron upright, fixed
to the headstock with screws at the foot, showing the circular grooves
1, 2 and 3, necessary for the spindles for the connecting wheels; the
centre hole, 4, is for the gun-metal collar, or the upper mandrel.
Fig. 402, is a plan of the mould for the front cast-iron upright; the
centre holes 1 and 2 are for the collars of the mandrels. No. 2 is
made to just fit over the steel collar of the lower mandrel, and is
fixed to the headstock by a brass rose and three screws; it is also
fixed at the foot with two screws to the headstock.
These two castings, 401 and 402, are bolted together with two bolts
and nuts through the holes 5 and 6, as shown in Fig. 400. Fig. 403,
is a back view of the additions, showing the cog wheels and their
connections, also the brass bearings for the lower mandrel required
when allowed to traverse. This was a solid piece of brass with a hole
bored out and ground to fit the mandrel. It was then drilled the whole
depth in two places, for two steel steady pins, _b_, _c_, made to fit
quite tight, and at both ends for bolts and nuts, _a_, _d_, afterwards
sawn in two with the circular saw, and when put together and two holes
drilled through the thickness for fixing it was put in its place,
adjusted, and re-ground on. The holes for fixing were very carefully
continued through the cast iron upright, and the whole was finally
fixed with two screw bolts and nuts.
Fig. 404, is a front view, showing the eccentric chuck, R, on the
upper mandrel, the slide of which when used is connected with the
bracket in the wall, Fig. 406, causing the whole apparatus to
oscillate in proportion to the eccentricity of the chuck on its
centres one of which is marked at S. The chuck has a circular movement
for laying the waves in any position with one another, but which also
is effected by another plan to be presently described. The whole
poppet with its fittings is hung on centres similar to the rose engine
described in this work. The top part of the bed T removes, and the two
screws, one shown at V, are taken out to allow the oscillation. The
large cog wheel has 192 teeth.
[Illustration: FIG. 400.]
[Illustration: FIG. 401.]
[Illustration: FIG. 402.]
[Illustration: FIG. 403.]
[Illustration: FIG. 404.]
[Illustration: FIG. 405.]
[Illustration: FIG. 406.]
The whole of the additions to my headstock were all of my own fitting
up. The brass cog wheels were bored out and ground to fit an arbor
made on purpose, exactly corresponding in diameter with the ends
of the spindles so that they might fit indiscriminately on either
spindle. When turned up, the teeth were cut with a circular cutter,
which I made just of the exact shape and thickness required for the
space between the teeth. The cutter was turned of steel; then wrapped
in leather and enclosed in sheet iron. It was then put in the fire,
made red hot, and left for the fire to go out, the next day being
soft, it was cut with sharp chisels into a circular file and hardened,
and with it in the cutter frame the teeth of the wheels were cut. The
central boss of each wheel has a notch cut across the face to receive
a pin in the arbor and in the spindles, which prevents the wheels from
turning round on the latter when screwed up.
This rose engine works beautifully smooth and easy, and ornamentation
can be done with it with greater rapidity than with the ordinary
engine, by arranging the connecting wheels so that the upper mandrel
makes so many waves and one-half, one-third, one-fourth, one-fifth,
one-sixth, or any other part of a wave, on each revolution of the
lower mandrel, because then it requires certain revolutions of the
lower mandrel before the tool comes into the same cut again--say,
for instance, it makes 4-5/6 waves on each revolution, then it takes
29 revolutions of the upper mandrel to complete the pattern, whereby
certain patterns are completed without stopping the lathe, which is
an advantage that the rose engine proper does not possess. Another
great advantage is, that the waves can be either flat, sharp, or
intermediate, as required for large or small work, by altering the
eccentric chuck on the upper mandrel.
I give a few specimens, not for the beauty of design, but to
illustrate the working of the engine. The centre of Fig. 407 is
performed by having a wheel of 80 teeth on the upper mandrel,
connected with one of 25 teeth on the intermediate spindle, which has
another of 50 teeth connected with the large wheel of 192 teeth on
the lower mandrel; thus, 80/25 50/190 = 1-1/5 producing on each
revolution of the lower mandrel one wave, and one-fifth of another
wave, requiring six revolutions to complete the pattern.
The remainder of the pattern is completed by wheels, 16, 50; 48, 192
making 12-1/2 waves on each revolution of the lower mandrel, requiring
25 waves to complete the pattern, and laying the waves over each
other, and with the slide rest movement of the tool.
Fig. 408 is produced by wheels 32, 48; 24, 192 making 12 waves. The
centre is done by altering the eccentric chuck each time. It was
purposely executed askew, by the tool not being placed in the centre,
to show the importance of doing so for some patterns. The rim was
executed with the same wheels, and with the slide rest movement of the
tool, and, after two cuts, the chuck turned half round, to lay the
waves over each other for the other two cuts.
Fig. 409 is all executed with wheels 96, 30; 25, 192 making two
waves and two-fifths of another wave, requiring 12 waves to complete
the pattern. The two centre rims produced by placing the tool above
the centre. The outside by four movements of the slide rest tool,
illustrating how soon patterns are produced, and when well cut up look
very pretty.
Fig. 410 is executed with wheels 80, 50; 25, 192 making four waves
and four-fifths of another wave, requiring 24 waves to complete the
pattern. The centre is all done without stopping; the outside rim by
altering the eccentric chuck four times, to make each successive wave
flatter.
Fig. 411 is an illustration of the upper mandrel, making 5-1/3
revolutions to one of the lathe, requiring 16 revolutions to complete
the pattern and slide-rest movement.
Fig. 412. The outer pattern of this figure is produced by the upper
mandrel making 12-4/5 revolutions to one of the lathe, requiring 64
revolutions to complete the pattern. The centre is a rosette of 5
waves, slide-rest movement and placed across each other.
[Illustration: FIG. 407.]
[Illustration: FIG. 408.]
[Illustration: FIG. 409.]
[Illustration: FIG. 410.]
[Illustration: FIG. 411.]
[Illustration: FIG. 412.]
Fig. 413. The whole of this pattern produced by the upper mandrel
making 3-3/5 revolutions to one of the lathe, producing 18 waves
across each other with slide-rest movement for the middle rim.
Fig. 414 illustrates a rosette of nine waves with slide-rest movement,
and 3 divisions of the circular movement of the eccentric chuck for
each successive line, producing the waved appearance.
Fig. 415 illustrates a rosette of 24 waves with the slide-rest
movement.
Fig. 416. Another illustration of a rosette of 24 waves, rather more
sharp than in Fig. 415, with slide-rest movement and 9 divisions of
the circular movement of the eccentric chuck, giving it a pleasing
circular waved appearance.
Fig. 417. Also another illustration as the last, but with the waves
much sharper, the slide-rest movement and only two divisions of the
circular movement of the eccentric chuck producing the star-like
pattern.
Fig. 418 illustrates also a rosette of 24 waves, with the eccentric
chuck turned half-way round with each movement of the slide-rest,
producing the pattern so often seen on the back of watches, only being
on wood it is on a larger scale.
[Illustration: FIG. 413.]
[Illustration: FIG. 414.]
[Illustration: FIG. 415.]
[Illustration: FIG. 416.]
[Illustration: FIG. 417.]
[Illustration: FIG. 418.]
The above illustrations are sufficient to give a distinct idea of the
working of my engine, and the last four show how easily patterns are
multiplied and varied.
The whole of the preceding patterns were executed by the wood being
chucked in the lathe in the usual ordinary way without any particular
chuck whatever, but in combination with any of the ornamental chucks
innumerable patterns can be produced.
Fig. 419 is one illustration with an eccentric chuck on the lathe
mandrel.
[Illustration: FIG. 419.]
That my description may be complete I will now give drawings of my
eccentric chuck for the upper mandrel. It requires to be constructed
differently to the ordinary eccentric chuck, as the circular movement
requires to be always _central_, and only the slide carrying the pin
to receive the rod must move eccentrically.
[Illustration: FIG. 420, also 422.]
[Illustration: FIG. 421, also 423.]
Figs. 420 and 421, are full-size drawings of my eccentric chuck on my
upper mandrel, used for producing the foregoing specimens. In this
case I have preferred a wood foundation, as not being so likely to run
off as metal, on reversing the motion which is sometimes necessary
on account of idle wheels for the connections. I used a piece of
well-seasoned Spanish mahogany, taking care that the grain of the
wood was at right angles with the length of the screw of the mandrel.
A piece of brass is screwed at the back to prevent the screw cutting
into the wood. Fig. 420 is a section, and Fig. 421 a front view of
the chuck, and I think all sufficiently clear. I will just say the
long fine threaded screw I cut up with the stocks and dies in the
lathe, using steel wire of the necessary size. This I manage easily,
and keep the wire straight _by allowing it to expand in length_. I
chuck the steel wire concentrically, and removing the centre from the
back poppet, substitute a brass centre with a hole the size of the
steel wire, which is allowed about a quarter of an inch entry. I then
turn down a little below the depth of the intended screw thread for
about half an inch in length next the back centre, to allow the dies
to come back to be tightened up, and which must only be done at the
commencement and not on the return motion of the dies. The collar on
the screw is a piece of brass with a hole of a size to drive on the
wire tight, and is then pinned on and turned up true, and finished
with the division marks.
OVAL TURNING AND ROSE CUTTING WITH TEMPLATES WITH MY
APPARATUS.
Figs. 422 and 423 are full size drawings of my chuck, with circular
movement for templates for my upper mandrel, which has also a wood
foundation. Fig. 422 is a section, and Fig. 423 is a front view.
By removing the eccentric chuck from the upper mandrel, and
substituting the chuck Figs. 422 and 423 with a circular movement,
to receive templates of any pattern, OVALS with the oval
template can be turned and also with any irregular templates, patterns
cut and placed in any direction over each other, by causing the
templates to work against a rubber or roller as most desirable, with
an india-rubber spring to keep them together.
The following illustrations will give some faint idea of productions
from templates.
Fig. 424, is the production of an oval template and slide-rest
movement, both mandrels making equal revolutions.
Fig. 425 the same as Fig. 424, with the patterns laid across each
other by turning the circular movement of the chuck 12 divisions.
Fig. 426, is from an oval template, which is caused to make two
revolutions to one of the lathe mandrel producing 4 waves and
undulations and with the slide-rest movement. It will be perceived in
this case the form of the _oval_ is superseded by another pattern, and
shows how great a change in the form of patterns from templates my
rose engine with change wheels effects.
Fig. 427, is also from an oval template, caused to make 5 revolutions
to one of the lathe, and with the circular movement of the chuck
and the slide-rest movement, and in this case the form of the oval
is also superseded. Indeed, none but those who have made the matter
their study would have the slightest idea that this pattern could be
produced from an oval template.
Fig. 428, is also from an oval template, it is finer than 427, but is
done in the same way by the template making _nine_ revolutions to one
of the lathe mandrel.
[Illustration: FIG. 424.]
[Illustration: FIG. 425.]
[Illustration: FIG. 426.]
[Illustration: FIG. 427.]
[Illustration: FIG. 428.]
The above are a few specimens of the oval, but sufficient to draw
attention to the great variety of patterns that can be executed,
and these illustrations have only been made to go even revolutions
with the lathe mandrel; but of course can be made to go, as already
described, uneven revolutions, laying the lines over each other for
variety of patterns.
Fig. 429, is a curiosity from a square template with equal
revolutions, the outside rim and inside pattern by the circular
movement of the template chuck.
Fig. 430, is also from a square template made to go two revolutions to
one of the lathe and with the slide-rest movement. The centre pattern
with the circular movement of the chuck.
Fig. 431, is the production of a heart-shape template, and with the
slide-rest movement and the patterns laid across each other, the
mandrels making equal revolutions.
Fig. 432, is also from a heart-shape template made to go two
revolutions to one of the lathe and the slide-rest movement. But in
this case the slide-rest tool is used _on the opposite side of the
lathe bed_ to the roller against the template, and therefore reversing
the pattern, that is, the projections of the pattern are the hollows
of the template, and _vice versa_. I have introduced it to show how
easily patterns are multiplied in the most simple way. It will also be
observed that the form of the template is superseded.
Fig. 433, is another illustration of the heart-shape template, but
made to go five revolutions to one of the lathe, with the circular
movement of the template chuck, and the slide-rest movement, and in
which case the form of the template is entirely superseded.
Fig. 434, is also a similar illustration to 433, only finer; they can
be of course as fine as desired.
The above are, I think, sufficient to illustrate the productions from
templates, some very pretty patterns can be executed. My object is
more particularly to exhibit the use and extended application of my
rose engine, and it will be perceived the last two are not the most
easily working templates.
The variety of patterns that can be executed with this engine are
so innumerable that one may say they are infinite. Well may you in
your article quote what Bergeron says of the rose engine, "that it is
necessary to know thoroughly the particular one in use."
I also make use of the cogwheel on my mandrel, by connecting it by a
spindle and the change wheels with a large compound slide rest, for
executing spiral turning, and also with my slide rest for ornamental
turning, for small spiral work; and with a chuck with a circular
movement I can cut several spirals to one stem.
[Illustration: FIG. 429.]
[Illustration: FIG. 430.]
[Illustration: FIG. 431.]
[Illustration: FIG. 432.]
[Illustration: FIG. 433.]
[Illustration: FIG. 434.]
In concluding my description I will say the specimens given have all
been cut on a plain surface, and this has been unavoidable on account
of printing, but for the information of those unacquainted with the
rose engine, the very great advantages of which over the eccentric
and geometrical chucks are that the work can be executed on concave
or convex surfaces. I make use of mine for ornamenting the roofs of
temples and Chinese pagodas, either domed, curvilinear, or circular
pointed, by representing them covered with shingles, &c. The geometric
chuck will produce very beautiful intricate lacework, but not more so
than my apparatus, as they both are on the same principle of change
wheels, and can both produce equally fine work; but with my apparatus
the work is always concentric with the mandrel, and therefore much
more pleasing to execute.