# Technical Drawing - Exam Papers - Ordinary - 2007 - Engineering

### Question 5

(Section A)   (Section B)   (Part A)   (Part B)   (Part C)

Answer SECTION A or SECTION B but not both.

SECTION A

(a) Fig.5(a) shows the elevation and end elevation of a machine casting. Draw an isometric view of the casting with the portion in front of the section plane A-A removed.
Point P is to be the lowest point on the drawing.

(b) Using large freehand sketches illustrate the following:
(i) Splined shaft;
(ii) Keyway;
(iii) Stud.

OR

SECTION B

(a) List six CAD commands necessary to produce the drawing in Fig.5(b).

(b) By means of sketches and a short note, explain the purpose of the following commands:
(i) Mirror;
(ii) Break;
(iii) Extend.

(c) Using a large freehand sketch, draw the object shown in Fig. 5(c) as a wireframe representation.

(d) Draw, full size, the object that would be displayed on a CAD system when the following commands are executed:
(All points (X,Y) are specified using absolute co-ordinates. The origin (0,0) is located at the lower left corner of the display)

• A rectangle is drawn with its lower left corner at (30,30) and its upper right corner at (190,65)
• The upper corners of the rectangle are chamfered 15 x 15
• A line joins the lower ends of the chamfer lines
• A line AB is drawn using the following co-ordinates: A (75,65) B (75,115)
• The line AB is offset 70mm to the right. This new line is indexed CD (point C is on top)
• A circular arc is drawn to pass through points B, C and point E (110,215)
• A 30mm diameter circle is drawn concentric with the arc
• A 16mm diameter circle is drawn with its centre at point (110,195)
• The circle is the subject of a circular (polar) array consisting of a total of 5 items. The centre of the array is located at the centre of the three point arc
• A rectangle is drawn with its lower left corner at (85,78) and its upper right corner at (135,102)