2018 Design & Communication Graphics (D.C.G.) Revision Notes covering the majority of the DCG syllabus through relevant exam solutions. Feel free to use these notes for study purposes only. Encrypted video links will not work through this platform but the notes should be clear enough to assist you in your understanding and comprehension of DCG learning areas. Best of luck to all students doing Irish Leaving Certificate exams this June (2018).
4. • FORMAT:
EXAM DURATION
HIGHER LEVEL = 3 HOURS
ORDINARY LEVEL = 3 HOURS
EXAM PAPER STRUCTURE
THREE SECTIONS IN EXAM PAPER
SECTION A = MIXED TOPIC SHORT QUESTIONS
FOUR SHORT QUESTIONS (ANSWER ANY THREE)
SECTION B = CORE GEOMETRY
THREE LONG QUESTIONS (ANSWER ANY TWO)
SECTION C = APPLIED GRAPHIC
FIVE LONG QUESTIONS (ANSWER ANY TWO)
EXAM GUIDANCE
5. • TIMING:
Higher & ordinary level: 3 hours (180 minutes)
Spend 3 to 5 minutes previewing exam paper at start
Section A: recommended time = 45 minutes max
Section B: recommended time = 65 minutes max (32.5 min/question)
Section C: recommended time = 65 minutes max (32.5 min/question)
Key tip: when studying, get into the habit of doing questions relative to the timing
suggested. When in the exam, have time ques or be vigilant of time during the exam to
remind you to progress from one question to another.
EXAM GUIDANCE
6. • SUGGESTED APPROACH: BE ‘SMART’…
Don’t panic, easy for me to say but really don’t panic. The exam paper will look different
because all of the questions are new and previously unseen. Take a minute to relax and
then confirm to yourself that you are refined in the methods /understanding to
answering such questions. Remember that year on year the face of the questions may
change but the detail is the same, the methods are consistent and there is a logical
sequence to be followed in all cases.
Upon review of exam paper, mark the questions you feel most confident about doing
Do section ‘a’ first and begin with whatever question you feel you can answer best
Move onto section ‘b’ and again begin with your strongest question
Move onto section ‘c’ and once more begin with your strongest question
In all cases, remember to double check what the question is asking you. It is not
uncommon to presume something or overlook something. Be dilligent here.
If all else fails just have a go. Do what you can and remember an auxiliary view here or
there will do no harm
If you have time at the end, spend it by reviewing the work you have done or tidying
up/finishing incomplete questions
Do not leave the exam hall without having attempted the required amount of questions
to the best of your ability.
EXAM GUIDANCE
7. A1 A2 A3 A4 B1 B2 B3 C1 C2 C3
2009 CONIC PERSPECTIVE AXONOMETRIC SOLIDS IN CONTACT OBLIQUE CO-ORDINATE GEOMETRY INTERPENETRATION STANDARD, RISING ETC.
HYPERBOLIC PARABOLOID
AND HYPERBOLOID OF
REVOLUTION
CONICAL SURFACE
DEVELOPMENT WITH CONIC
FOCAL SPHERE ETC.
2010 SKEW LINES AXONOMETRIC CONIC OBLIQUE PERSPECTIVE OBLIQUE CO-ORDINATE GEOMETRY STANDARD, RISING ETC. HYPERBOLIC PARABOLOID
OVEN HOOD STRUCTURE WITH
CYLINDRICAL SURFACE
DEVELOPMENT
2011 AUXILIARY CONIC SKEW LINES SOLIDS IN CONTACT INTERPENETRATION AXONOMETRIC DIMETRIC CONIC STANDARD, FALLING ETC. HYPERBOLIC PARABOLOID ROOF STRUCTURE - USUAL
2012 AXONOMETRIC AUXILIARY ROTATION PERSPECTIVE CONIC INTERPENETRATION CO-ORDINATE GEOMETRY STANDARD, FALLING ETC.
HYPERBOLOID OF
REVOLUTION
ROOF STRUCTURE - USUAL
2013 ORTHOGRAPHIC SOLIDS IN CONTACT INTERPENETRATION SKEW LINES OBLIQUE AXONOMETRIC DIMETRIC PERSPECTIVE AND SKEW LINES STANDARD, FALLING ETC.
SHELL TRANSLATION
STRUCTURE
DIAMOND SUFACE
STRUCTURE, USUAL
2014 ORTHOGRAPHIC OBLIQUE CONIC PERSPECTIVE CO-ORDINATE GEOMETRY AXONOMETRIC TRIMETRIC AUXILIARY STANDARD, RISING ETC.
SHELL TRANSLATION
STRUCTURE
ROOF STRUCTURE - USUAL
2015
OBLIQUE
PLANES/ORTHOGRAPHIC
CONIC
CO-ORDINATE
GEOMETRY/OBLIQUE PLANES
SKEW LINES AUXILIARY/CONIC
AXONOMETRIC/
INTERPENETRATION
PERSPECTIVE
STANDARD, ROAD RISING,
THICKNESS OF STRATUMAND
VERTICAL PROFILING
HYPERBOLIC PARABOLOID
WITH AUXILIARY AND SKEW
LINES
ROOF STRUCTURE - USUAL
2016 DEVELOPMENT ORTHO OBLIQUE CONIC HYPERBOLA ORTHOGRAPHIC/AUXILIARY CO-ORDINATE GEOMETRY CONIC OBLIQUE ORTHO-INTERPENETRATION STANDARD
HYPERBOLOID OF
REVOLUTION
TRANSITION PIECE
DEVELOPMENT
2017 AXONOMETRIC CONIC
OBLIQUE
PLANES/ORTHOGRAPHIC/
SURFACE GEOMETRY
ORTHOGRAPHIC/AUXILIARY CONIC CO-ORDINATE GEOMETRY PERSPECTIVE STANDARD
SHELL TRANSLATION
STRUCTURE
ROOF STRUCTURE - USUAL
2018? CONIC SKEW LINES PERSPECTIVE ORTHOGRAPHIC/AUXILIARY OBLIQUE INTERPENETRATION AXONOMETRIC STANDARD HYPERBOLIC PARABOLOID
ANGULAR & CURVED
STRUCTURE
2018 LEAVING CERTIFICATE: DESIGN & COMMUNICATION GRAPHICS - PREDICTOR MODEL
SECTION A SECTION B SECTION C
EXAM QUESTION TRENDS
JUST A GUESS!
45. A
B
C
D
A
B
C
D
E
B
D
E
F
B
D
E
B
D
A
BC
D
E
F
A
B
C
D
E
Q
Q
R
R
CO-ORDINATE GEOMETRY 2016 HL: TYPE 1 – COMMON LINE
‘AB’ LINE OF INTERSECTION
‘AB’ LINE OF INTERSECTION
‘AB’ LINE OF INTERSECTION
TRUE LENGTH
DIHEDRAL ANGLE ‘ABC’ & ‘ABD’
θ
INCLINATION OF ‘BDE’ TO HP
USING LEVEL LINE METHOD
A GIVEN DIHEDRAL ANGLE
‘REVERSE ENGINEERING’
COMBINING ELEVATION HEIGHTS
BY AUXILIARY VIEW &
APPLY HERE
TAKE DISTANCE ‘Q’ AND
PART C
PART D
PART A
PART B
θ
F
F
47. X Y
A
B
C
A
B
C
A
B
C
A
B
C
D
E
F
D
E
FD
E
F
D
E
F
DIHEDRAL ANGLE
CO-ORDINATE GEOMETRY: TYPE 3 – NO COMMON LINE OR POINT
X2Y2 PERPENDICULAR TO TL OF LOI
MEASUREMENTS TAKEN FROM X1Y1 BACK TO
POINTS IN PLAN VIEW
X1Y1 PARALLEL TO LOI IN
PLAN VIEW
MEASUREMENTS TAKEN
FROM XY TO POINTS IN
ELEVATION
YOU MIGHT HAVE STARTED THIS THE LAST DAY
AFTER TAKING PHOTO OF QUESTION
50. DATUM LINE
IN THIS CASE, USED TO
SHORTEN THE DISTANCES
TAKEN FOR POINTS IN THE
SECOND AUXILIARY VIEW
X2Y2
A
B
C
D
E
F
H
θX1
Y1
X2
Y2
X1
Y1
X Y
V
T
H
A
B
C
D
A B
C
D
E
F
A
B
C
D
E
F
A
B
C
D
E
F
PART A
PART B
PART C
PART D
H
ALSO FOR POINT E
55.
AUXILIARY VIEW 1
AUXILIARY VIEW 1
AUXILIARY VIEW 1
AUXILIARY VIEW 1
AUXILIARY VIEW 2
AUXILIARY VIEW 2
AUXILIARY VIEW 2
DATUM LINE FOR
AUXILIARY VIEW 2
DATUM LINE FOR
AUXILIARY VIEW 2
LEVEL LINE
LEVEL LINE
LEVEL LINE
LEVEL LINE
73. ELLIPSE BY CONCENTRIC
CIRCLES
FIND ELLIPSE GIVEN POINT
ON CURVE AND MINOR
CIRCLE
FIND ELLIPSE GIVEN POINT
ON CURVE AMD MAJOR
CIRCLE
GIVEN POINT ON CURVE,
FIND TANGENT
GIVEN POINT OFF CURVE,
FIND TANGENT(S)
F1 F2
PARABOLA
83. HL 2017
CUT 1.5 X 5 = 7.5MM
FILL 2 X 5 = 10MM
@A 65M TO @B 65M IS LEVEL
@B 65M - @C 50M = FALL 15M
CONTOURS ON SECTION B TO C ABOVE
FORMATION LEVEL, THUS NEED TO BE CUT.
CUT CONE CALCULATION
FALL 15 X 1.5 = 22.5
CONE R = 22.5
@C 50M TO @D 50M IS LEVEL
65
50
99. -CONT. 5M VERT. INT.
-A TO B LEVEL @40M
-B TO C 1 IN 15 RISING
-CUT 1:1 (1x5=5)
-FILL 1:1.5 (1.5x5=7.5)
40M
45M
50M
55M
60M
CUT 1:1 (1x5=5)
TRAVEL 150M AND RISE 10M FROM B TO B1
B1
AREA NEEDS TO BE FILLED TO RISE ROAD AS CONTOURS ARE BELOW FORMATION
LEVEL OF 40M, THUS WE REQUIRE A FILL CONE.
STEP 1
STEP 2
STEP 3
FILL CONE CALCULATION
RISE VALUE @ B1 x FILL RATIO
10M x 1.5 = 15M; THUS CONE R=15M
X1
Y1
X2
Y2
45°
D = 35M
MR. LYSTER: NOTES
40M
35M
30M
25M
20M
Z
SKEW BOREHOLE AT ‘D’
DRILLED IN NORTHERLY
DIRECTION IN PLAN
HL 2009
120. pc
pc pc
pc
pc
SOLIDS IN CONTACT
FIND SPHERE IN POSITION ‘C’ WITH R=20 TO TOUCH CONE ‘A’ AND CYLINDER ‘B’.
R=35 R=25
110
90A
A
B
B
C
SUPPLEMENTARY
SOLIDS IN CONTACT