UNIVERSITY OF MALTA
SECONDARY EDUCATION CERTIFICATE
SEC
GRAPHICAL COMMUNICATION
May 2012
MARKING SCHEME
MATRICULATION AND SECONDARY EDUCATION
CERTIFICATE EXAMINATIONS BOARD
PAPER 1
Ellipse / Normal /Tangent
Question No. 1
(a) proper construction of the ellipse, using any recognized method
(b) locating the position of the focus and constructing the tangent to
the ellipse at the given point X1 and at X 2
(c) constructing the normal to the ellipse at the given point Y1 and Y2
(d) locating the centres of the R40 arcs on the normals
(e) completing the outline of the vase
Total marks for question No. 1
Tangential Arcs / Circles in Contact
Question No. 2
drawing the 10 mm radius arc on the given centre
drawing the 6mm radius arc on the given centre
adding 10+105 and 6+105 and drawing two arcs from their respective
centres to intersect each other
drawing the 105 mm radius arc from the centre of the intersected arcs
tangential to the 10mm and 6mm radius arcs
drawing the 45mm radius arc
adding 10+10 and drawing the 20mm radius arc from the 10 radius arc
adding 10 + 45 and drawing the 55mm radius arc to intersect the
20mm radius arc
drawing the 10mm radius arc from the centre of the intersected arcs
tangential to the R10mm and the R45mm arcs
blending the arc of 17mm with the 6 mm radius arc
drawing the 22mm radius arc tangential to the given horizontal line
constructing the 36mm radius arc blending with the radius 22mm arc
neatness and presentation
Total marks for question No. 2
Construction of angles and triangle
Question No. 3
bisecting two chords to locate the centre of the front wheel
completing the wheel
locating by construction the centre of the 12mm radius arc
tangential to the produced line ST and the centre of the front wheel
constructing by compasses the angles PQR and PQT
constructing the triangle PQR
drawing the horizontal line SR
lining in the bicycle by bold lines / neatness and presentation
Total marks for question No. 3
2
4
3
2
2
1
12
1
1
2
1
1
1
1
1
1
1
1
1
13
2
1
2
3
3
1
1
13
Orthographic view
Question No. 4
positioning and locating the end view of the cast iron bracket
locating and drawing the Ø36mm x 50mm top cylinder
drawing of the two horizontal lines representing the Ø 14mm hole
locating and drawing the Ø 14 circle representing the other hole drilled at right angles
drawing of the 10mm base of the bracket / 8mm step and centre lines
locating and drawing the 10mm middle web
drawing of the left and right bottom webs
placing all fillet radii
drawing correctly all hatching lines
N.B. deduct 2 marks for incorrect section lines
neatness and presentation
Total marks for question No. 4
3
1
2
1
1
2
1
1
1
3
1
14
PAPER 2A
True shape and Development
(When the curve marked A is considered as part of the circumference)
Question No. 5 (a)
projecting construction lines from the given points on the rim of the mug
2
(in the plan view) to the circle enclosing the cross in the front elevation
measuring the chordal distances from the plan and transferring points
2
accurately on the given diagram representing the development of the
sticker
drawing vertical construction lines from the marked points on the flat
2
sticker
drawing projection lines from the intersection of the points of the Front
2
onto the respective vertical construction lines measured from the plan
locating and drawing the true profile of the curve marked A
2
Total marks for question 5 (a)
10
Question No. 5 (b)
locating the 13 points of intersection of the Maltese cross
joining the appropriate points of intersections by means of short lines to
form the profile of the elongated Maltese cross marked B
accuracy neatness and presentation
Total marks for question 5 (b)
Total marks for question No. 5 (a) and (b)
4
14
1
2
1
OR
True shape and Development
(When the curve marked A is considered as an ellipse)
Question No. 5 (a)
determining the major axis of the ellipse by measuring the distance from
the right and left edges of the sticker to the curve marked A
(measurement taken from the plan)
determining the minor axis of the ellipse by measuring the distance from
the top and bottom edges of the sticker to the curve marked A
(measurement taken from the front elevation)
drawing the ellipse using an approved method of construction
Total marks for question 5 (a)
Question No. 5 (b)
projecting horizontal construction lines from the points of the cross on
the front elevation to the ellipse on the sticker
joining the appropriate points of intersections by means of short lines to
form the profile of the elongated Maltese cross marked B
accuracy neatness and presentation
Total marks for question 5 (b)
Total marks for question No. 5 (a) and (b)
4
2
2
5
9
2
2
1
5
14
Oblique projection
Question No. 6
drawing a crate of 120mm x 70mm x 35mm
drawing the two (Ø30 and Ø40) concentric front circles (Deduct 0.5 if not in position)
drawing of the Ø 30 circle representing the lens
drawing the two (Ø40 and Ø50) concentric circles
drawing the Ø50mm rear circle touching the front body of the camera
drawing a rectangle 0.5 depth, 12 x 70 x 15 representing the body of the camera
lining in the body of the camera excluding the two chamfers
drawing the two 10mm x 5mm left and right chamfers
locating and drawing the 48mm x 8mm left top button
locating and drawing the 20mm x 8mm x 2mm flash
locating and drawing the three Ø10 lenses
lining in neatly the outline
Total marks for question No.6
Two Point Perspective View
Question No. 7
drawing the whole perspective view within the given crate
constructing an appropriate perspective ratio (diagonal, point M or
intuitive estimate) so that objects that are closer appear bigger
locating and drawing the two uprights
locating and drawing the lower shelf (45mm x 90mm)
locating and drawing the middle shelf
locating and drawing the bricks and oven
locating and drawing the pyramidal part of the canopy
locating and drawing the prismatic part of the chimney
neatness and presentation
Total marks for question No. 7
Polygon of forces
Question No. 1
Force 1 (F1): Angle 0.5; Scaled 0.5; Magnitude 0.5; Arrows
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
1
1
1
1
1
2
2
2
1
1
2
1
16
1
3
2
2
2
2
3
2
1
18
1.5
(however students were penalized only once, full marks given in magnitude below)
Force 2 (F2) Angle 0.5; Scaled 0.5; Magnitude 0.5; Arrows
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
(however students were penalized only once, full marks given in magnitude below)
5
1.5
Force 3 (F3) Angle 0.5; Scaled 0.5; Magnitude 0.5; Arrows
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
1.5
(however students were penalized only once, full marks given in magnitude below)
Force 4 (F4) Angle 0.5; Scaled 0.5; Magnitude 0.5 Arrows
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
1.5
(however students were penalized only once, full marks given in magnitude below)
Measuring (M) F3 (0.5)
F4 (0.5)
Conversion (C) F3 (0.5)
F4 (0.5)
Magnitude (M) F3 (0.5)
F4 (0.5)
Direction (D) F3 (0.5)
F4 (0.5)
Total marks for question No. 1
Computer Programme
Question No. 2
producing the image of the lable by plotting and drawing the :
4 lines representing the CAMERA (0.5 each line) = 2
colour GREEN = 1
3 lines representing the LENS
(0.5 each line) = 1.5
colour RED
= 0.5
3 lines representing VIEWER
(0.5 each line) = 1.5
colour RED
= 0.5
5 lines representing BASE
(0.5 each line) = 2.5
colour BLUE
= 1
2 lines representing the HANDLE (0.5 each line) = 1
colour BLACK = 0.5
Total marks for question No. 2
1
1
1
1
10
3
2
2
3.5
1.5
12
Archimedean Spiral
Question No. 3
dividing accurately the distance AC into equal parts
18 parts
15 parts deduct -2
12 parts deduct -2
dividing the circle into twelve equal sectors
rotating and locating the relevant points onto the correct position of
the radial lines
18 points
12 points deduct -2
an other number of points deduct -3
plotting and drawing the path of the point from A to C
6
4
2
4
2
deduct -1 point for drawing cirve without points
lining in using the proper outline by a smooth curve
Total marks for question No 3
2
14
Safety Sign
Question No. 4 (a)
colouring the given three signs using proper colours
Blue
–
(1 mark)
Black – outer & inner (0.5 + 0.5)
Yellow
–
(1 mark)
Red
–
(1 mark)
Total marks for question No. 3(a)
Question No. 4 (b)
(i) depicting the safety signs in the given circle by drawing the
(i)
goggles
N.B. no instruments used and looks messy: deduct -1 or - 0.5
looks like normal reading glasses:
deduct -1
if words are added:
deduct -2
(ii)
face
(iii) if too much detail in face deduct -1
colouring (b) Blue background
White outlines
N.B. if glasses and face are drawn but no white line deduct -1
if glasses only are drawn but used black line or pencil deduct -0.5
if glasses only are drawn with no need of white lines give
Total marks for question No. 4 (b)
4
4
4
3
2
1
(1 only)
10
Total marks for question No. 4 (a) and (b)
Auxiliary View
Question No. 5
dividing the circle in the end view by an adequate number of parts
projecting horizontally these points onto the circumference of the
semi-circle on the front view
projecting the lines from the front view at the given angle to the
auxiliary view
carefully measuring the widths from the end view and transferring
these widths on the projected lines of the auxiliary view
lining in the shape produced on the left hand side of the card
lining in the shape of the card on the right hand side of the card
completing the auxiliary view by drawing the heart shape by bold lines
and a smooth curve
Total marks for question No. 5
7
14
1
2
3
5
2
2
1
16
True lengths and True shape
Question No. 6 (a)
finding the true lengths of the easel’s legs by adopting a recognized
approved method ( construction shown clear)
(i)
true length of leg AB = 120mm
(ii)
true length of leg AC = 120 mm
(iii) true length of leg AD = 112 mm
(iv)
true length of rod PQ = 47 mm
Total marks for question No. 6 (a)
Question No. 6 (b)
using proper construction to obtain the true angle of AB to the
horizontal 65 degrees
Total marks for question No. 6 (b)
Question No. 6 (c)
method showing how the height of the board is found - 48mm
measuring the length of the board from the plan - 46mm
Total marks for question No.6 (c)
Total marks for question No.6 (a), (b) and (c)
Curve of Intersection and Development
Question No. 7 (a)
dividing the circle in the plan into a number of parts
projecting these point by light lines onto the front and end view
locating the intersecting points from the curve of the front view to the
respective intersecting vertical lines of the end view to obtain the
curves of intersection to complete the view
lining in neatly by bold lines the curves of intersection requested
Total marks for question No. 7 (a)
Question No. 7 (b)
measuring the chordial distances from the plan and transferring these
distances on the given girth horizontal line of the development
by projecting the intersecting lines from the front view, locating the
points to obtain the required lower curve of the surface development
lining in neatly by a bold curve the outline of the development
Total marks for question No. 7 (b)
Total marks for question No. 7 (a) and (b)
8
3
3
3
3
12
1
1
2
1
3
16
2
2
4
1
9
4
4
1
9
18
PAPER 2B
Polygon of forces
Question No. 1
Force 1 (F1): Angle 0.5; Scaled Magnitude 0.5; Arrows 0.5
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
1.5
(however students were penalized only once, full marks given in magnitude below)
Force 2 (F2) Angle 0.5; Scaled Magnitude 0.5; Arrows 0.5
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
1.5
(however students were penalized only once, full marks given in magnitude below)
Force 3 (F3) Angle 1; Scaled Magnitude 1; Arrows 1
deduct: -0.5 if not connected in a polygon
″
-0.5 if magnitude is off by more than 1N
3
(however students were penalized only once, full marks given in magnitude below)
Measuring (M)
Conversion (C)
Magnitude (M)
Direction (D)
F3 ( 1 )
F3 ( 1 )
F3 ( 1 )
F3 ( 1 )
Total marks for question No. 1
4
10
Computer Programme
Question No. 2
producing the image of the lable by plotting and drawing the :
4 lines representing the CAMERA (0.5 each line)
= 2
colour RED
= 2
4
NOTE: 1 mark awarded if used the correct colour but in haphazard lines
3 lines representing the LENS
(0.5 each line)
colour BLUE
=
=
1.5
1.5
NOTE: 1 mark awarded if used the correct colour but in haphazard lines
3 lines representing VIEWER
(0.5 each line)
= 1.5
colour GREEN
= 1.5
NOTE: 1 mark awarded if used the correct colour but in haphazard lines
2 lines representing HANDLE
(0.5 each line)
= 1
colour BLACK
= 1
NOTE: 0.5 awarded if used the correct colour but in haphazard lines
Total marks for question No. 2
3
3
2
12
Archimedean Spiral
Question No. 3
dividing accurately the circle into a number of sectors ( 12 parts )
dividing the distance PQ into the same number of parts ( 12 parts )
NOTE: If the number of parts are not equal to the number of sectors deduct
3
3
-1.5
rotating and locating the relevant points onto the correct position of
the radial lines
9
6
NOTE: If points joined are not mcorresponding deduct -2
lining in using the proper outline by a smooth curve
NOTE: Overall 1mark awarded if the curve is drawn without points
Total marks for question No 3
Safety Sign
Question No. 4 (a)
colouring the given two signs using proper colours
Outer Black
–
(1 mark)
Inner Black
–
(1 mark)
Inner Yellow
–
(1 mark)
Outer Red
–
(1 mark)
Total marks for question No. 3(a)
Question No. 4 (b)
(i) depicting the safety signs in the given circle by drawing the
(i)
Safety boots
N.B. If word are added deduct 2 marks
Colour:
(i)
Blue
–
2 marks
(ii)
White
–
2 marks
Total marks for question No. 4 (b)
2
14
4
4
6
4
10
Total marks for question No. 4 (a) and (b)
14
Auxiliary View
Question No. 5
dividing the front and plan view into an adequate number of parts by
drawing vertical construction lines
projecting these lines at 45 onto the printed X-Y line
carefully measuring the widths from the plan and carefully transferring
these widths on the lines constructed to draw;
(i) the top ellipses at the top representing the disc
(ii) the rectangular base of the scale
(iii) the lower part representing the digital dial of the scale
lining in the complete drawing of the scale by means of neat, bold
lines and smooth curves to produce a neat presentation of the scale
Total marks for question No. 5
True Lengths and True Shape
Question No. 6 (a)
finding the true length of the easel’s legs by adopting a clear
construction which may be easy to follow
(i)
True length of leg AB & AC 120mm,
(ii)
True length of leg AD 112mm
Total marks for question No. 6 (a)
10
2
2
4
3
3
2
16
6
3
9
Question No. 6 (b)
using proper construction to obtain the true length of the sloping line
of the easel’s board
measuring the horizontal line of the easel’s board from the plan
inserting the answers found, in the space provided
Total marks for question No. 6 (b)
Total marks for question No. 6 (a) and (b)
Line of Intersection and Development
Question No. 7 (a)
dividing the circle in the given plan into a number of parts
projecting these point by light lines vertically downwards onto the end
view and onto the front view
drawing horizontal lines from the intersection of these lines with the
sloping face of the front view to the end view to locate and plot the
curve of intersection so as to complete the view
drawing the curve of intersection by a bold neat curve
Total marks for question No. 7 (a)
Question No. 7 (b)
measuring the chordial distances from the plan and transferring these
divisions on the given horizontal line of the development
drawing horizontal projection lines from the front/end view, to locate
the points of the lower curve of the required development
lining in neatly by bold lines the outline of the development
Total marks for question No. 7 (b)
Total marks for question No. 7 (a) and (b)
11
4
2
1
7
16
2
2
4
1
9
4
3
2
9
18