Armengaud, Jacques Eugène; Leblanc, César Nicolas   [Hrsg.]; Armengaud, Jacques Eugène   [Hrsg.]; Armengaud, Charles   [Hrsg.]
The engineer and machinist's drawing-book: a complete course of instruction for the practical engineer: comprising linear drawing - projections - eccentric curves - the various forms of gearing - reciprocating machinery - sketching and drawing from the machine - projection of shadows - tinting and colouring - and perspective. Illustrated by numerous engravings on wood and steel. Including select details, and complete machines. Forming a progressive series of lessons in drawing, and examples of approved construction — Glasgow, 1855

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ENGINEER AND MACHINIST’S DRAWING-BOOK.

The construction and action of the machine having thus
been considered, the sketch may be commenced. In the
first place, a general elevation, Fig. 1, should be sketched,
in outline, to show the disposition of the pieces. A centre
line is first raised for the column, then a parallel centre
line for the vertical spindle, and a horizontal centre line
for the cone-spindle. These main centre lines may be
drawn in by the aid of a straight edge, or from the edge
of the rule—to give neatness and something like precision
to the sketch. The outline of the column may next be
drawn in, and the mouldings sketched; then the centre
lines for their brackets, and their outlines; and, lastly, the
table in outline. The bevil gear connecting the cone
and drill spindles, is expressed by the fundamental tri-
angles, as sketched, and the spur gear at the upper end of
the spindle, is shown, for explicitness, by two circles,
though literally the gearing is visible edgewise.

Dimensions must now be taken and written on the
sketch. First, the height of the column. This cannot be
measured directly upon the column, as the projections are
in the way; but a plumb-line dropped from the beam
resting upon the column, to the floor, will give the height
directly; or two light pieces of wood may be slid in con-
tact on one another, one to reach the beam above, while
the other rests on the floor, and the distance measured upon
them. The diameter of the column, at top and bottom,
should now be taken by callipers, and measured, and
written on the sketch at the proper places; or, a tape
line, cord, or flexible rule, may be passed round the
column, and the circumference, so measured, multiplied
by 7, and divided by 22, to give the diameter. The other
dimensions marked on the sketch sufficiently indicate the
nature of the succeeding operations, and do not require
further remark. The vertical range of the table is indi-
cated by two horizontal lines, the positions of which are
duly defined by figures.

The details remain to be sketched, and they are bet-
ter done in detached pieces, as shown, as there is thus
liberty to sketch the parts to any size, and as roomily as
may be required for the free insertion of dimensions.
Figs. 2 and 3 give the detail of the middle bracket, with
the bevil gearing in its place; and, as neither of these
views shows precisely the section of the casting behind
the bearing for the spindle, a detached section, Fig. 4, is
given and figured. Similarly, the sketch, Fig. 5, shows
the form of the spindle-bearing and cover, with the bolt-
holes ; and Fig. 6 is a section of the bearing for the cone-
spindle, behind the bevil pinion, showing the bushes and
bolts. Fig. 7 shows the spur gear in section, laying bare
the spindles and their connection with the wheel and
pinion. To arrive at some of these details, it is, of course,
necessary that the machine be dismembered. In sketch-
ing wheel-work, it is sufficient to show the nave, webs,
and rim in section, as in Figs. 2 and 7; a section of one
arm, Fig. 8, if there be arms; and a small portion of the
rim with a few teeth, and one arm, as in Fig. 3. The
number of the arms and the teeth in each wheel must
then be counted and written down. Each detail figure

O

should be completely sketched before the sizes are marked,
and care should be taken that the leading dimensions of
each piece should tally with those given on the general
sketch, Fig. 1.

Figs. 9, 10, 11, show a vertical section, plan, and side
view of part of the table with the vice-jaws and the set-
screw. Fig. 12 shows in section the lower end of the
spindle, with the drill-bit inserted and held by the set-
screw. Fig. 13 is a section of the cone-pully. Figs. 14
and 15, show the union of the upper end of the vertical
spindle with the screw; and Figs. 16 and 17 completely
detail the mechanism for adjusting the level of the table
and fixing it.

To facilitate the process of sketching, cross-ruled paper
is sometimes used, the parallel lines acting as guides for
the pencil. Sketches so made are illustrated by Figs. 9,
10, and 11.

Undershot Water-Wheel.—Plate XLY.

The water-wheel is composed of the centre, the spokes,
and the floats, constructed and put together as shown in
the engraving. The wheel works in a circular channel or
race at the lower side, formed concentrically with it, and
with sides, to embrace it closely and properly to confine the
action of the water upon the floats. The shroudings, A,
receive the radial wooden bearers, B, which carry the
floats, C. The shrouds are, in this case, of cast-iron, and
are in one piece with the arms, D, and the centre E,
keyed on the cast-iron shaft, F. The water-channel, G, is
capped with a cast-iron necking, H, bedded on the cross
timber piece I. The wooden sluice, J, works on the
necking, and by its elevation, adjusted by gearing, it
regulates the flow of the water over it. The motion is
taken off by the spur wheel, K, on the water-wheel
shaft, working into the pinion L, on the main shaft of
the machinery.

The channel, G, is of mason-work, the outward joints
of which converge towards the centre of the wheel. The
running surface should be truly cylindrical, and con-
centric with the wheel. A cavity, M, is made to receive
the sluice when lowered down, and is backed by a ridge
of mason-work, designed to arrest heavy floating bodies,
as trees.

The wheel is shown with two kinds of floats, on the
upper and lower halves respectively.

The shrouding, A, of cast-iron, is lightened by the for-
mation of panels, as at h, i, in the elevation, Fig. 1; and in
section, Fig. 2, taken on the line 1—2. It is cast with
mortises to receive the tenons or ends of the bearers
B, which are placed in the position of radii of the wheel,
and are fixed by iron keys, j, on the inside of the shroud-
ings. In some cases, the bearers are simply let into open
dovetail seats, as in Figs. 3 and 4, and fixed with a wedge j;
on this plan, it is unnecessary to pierce the bearers for the
cotters, as required in the first arrangement, Fig. 1.

When the shroudings are of wood, they are put toge-
ther in pieces, joined with mortise and tenon joints, as in
Figs. 5 and 6, and with iron plates, h, fixed with bolts, and
loading ...