Do not draw view A, as shown, nor the parts detached from one another, but :—

Scale,

In the place of view A, draw a corresponding sectional elevation with the parts assembled; also :

To the right of the sectional elevation, draw an outside elevation looking in the direction of the length of the cross-head; also:

Below the sectional elevation, draw a plan.

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Only as much of the spring as is shown is required to be drawn, and screw threads should be indicated conventionally and not drawn precisely.

Alternative Example 3, Diagram X.

Portion of the Back Gear of a Lathe.

On the diagram the component parts are shown more or less detached from one another. The wheel B has 63 teeth of 0.45" pitch, and the wheel which gears with it has 21 teeth. The hand lever C, as shown, is in the out-of-gear position.

Do not draw the parts separated as shown, but :

Having estimated the diameter of the wheel B and the distance of its centre from the lathe spindle :

Draw an end view of the upper portion of the Fast-HeadStock showing the parts assembled with the wheels in gear.

Below this:

Draw a sectional plan taken through the axes of the lathe spindle and the back spindle.

Also to the right of the end view :

Draw an elevation as viewed from the back of the lathe.

The hand lever C is required to be drawn in the end view only, and in the in-gear position. In the other views it may be indicated by its centre line. Draw the pitch circles and not the teeth of the spur-wheels.

Scale, .

Questions, only three to be answered.

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The Sketches in answer to these questions should be drawn freehand on the squared foolscap paper.

(a.) Explain the use of the back gear of a lathe, and describe how the construction shown in Example 3, Diagram X, is adapted to put the back shaft in and out of

gear.

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(b.) Give sketches showing how the cutting tool of a lathe or other machine is secured in place.

(8) (c.) Give sketches showing the construction of a divisible pulley, having a wrought metal rim, such as may be inserted on a shaft without threading it over the end.

(8) (d.) Sketch a connecting rod end with strap, gib, and cotter, and explain the use of the gib. (8) (e.) By means of sketches and a description, show how a steam-tight joint is made between a cylinder and cylinder cover. Show in detail the fitting of the bolt connection generally employed and, when the cover carries a stuffing box, show how its concentricity with the axis of the cylinder is ensured. (8) (f) When energy is transmitted along a line of pipes by means of high pressure fluid, a sluice or screw down valve or turn-cock is employed to temporarily intercept the flow of energy: when electrical energy is transmitted along a cable, a counterpart device is wanted. Give sketches showing a suitable construction for the purpose when the flow of electrical energy is considerable

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SUBJECT II. MACHINE CONSTRUCTION AND DRAWING.

Stage 2, Stage 3, and Honours.

Before commencing your work, you must carefully read the following instructions:

You may take Stage 2, or Stage 3, or, if eligible, Honours, but you must confine yourself to one of them.

A table of logarithms and functions of angles and useful constants is supplied for each Candidate on whose behalf application has been made for a paper in Stage 3 or Honours.

Put the number of the question before

your answer.

You are expected to prove your knowledge of machinery, as well as your capability of drawing neatly to scale. You are therefore to supply details omitted in the sketches, to fill in parts left incomplete, and to indicate, by diagonal lines, parts cut by planes of section.

No credit will be given unless some knowledge of projection. is shown, so that at least two views of the example selected will be required, properly projected one from the other. The centre lines should be clearly drawn. The figured dimensions need not be

inserted.

Your answers should be clearly and cleanly drawn in pencil, except the portion specified to be done in ink.

In Stage 2 the answers to the questions, as well as the drawings, should be made on the numbered paper supplied, comprising one sheet of drawing paper with tracing paper and squared foolscap attached. The tracing paper may be detached for the purpose of making the tracing, and must be carefully re-attached.

The value attached to each question is shown in brackets after the question.

You are to confine your answers strictly to the questions asked.

The examination in this subject lasts for four hours.

Stage 2.

Read the General Instructions on pages 3 and 4.

Trace in ink on the tracing paper supplied, the PEDESTAL shown in Example 1 on Diagram Z at the back of the accompanying Diagram Y.

The lines are required to be of uniform and moderate thickness, and as perfectly black and continuous as possible.

The number of marks allotted for the tracing is 30.

Draw either Example 4 or Example 5, Diagram Y, but not both.

It should be drawn on the side of the paper on which the Candidate's number is printed.

Also answer any three, but not more than three, of the questions (g), (h), (i), (k), (1), (m).

Example 4, Diagram Y.

Double Spring-loaded Safety-valve for Boilers. View P is a sectional elevation taken along the line P P4 of figure Q, and :

View Q is a plan with parts removed.

The other figures show details.

Do not draw the views shown, but:

Draw with the parts assembled a sectional elevation for the upper portion, is to be taken along th P5 P6 P7 Ps of figure Q, looking from left to and for the lower portion along the middle line P8 I Draw also a sectional plan, the section being taken th R1 R2 of figure P.

Scale,

Draw on the side containing the Candidate's number.

Alternative Example 5, Diagram Y.

Four-Pole Electric Motor.

Figures S and T are outside views showing the gen arrangement of the Motor, and the other figures show the det requisite for the purposes of this example.

Do not draw the views as shown, but :—

Draw a vertical elevation looking in the direction oppos to that shown in figure S, the upper half being an outs view and the lower half a view with the plate removed, also:

:

Draw a vertical side elevation of the portion of the Mot on the right of line T2 of figure T, the upper half being middle plane section and the lower half an outside view

Scale, 3.

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Break off a sufficient amount of the flange of T1 to get th views on the paper, and draw on the side of the paper containin the Candidate's number.

Questions, only three to be answered.

The sketches in answer to these questions should be drawn freehand on the squared foolscap paper.

(g.) Make sketches and give a description of some construction to provide for the expansion and contraction of a long length of steam pipe.

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