TECHNICAL DRAWING & DESIGN

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1 MINISTRY OF EDUCATION FIJI SCHOOL LEAVING CERTIFICATE EXAMINATION 2011 TECHNICAL DRAWING & DESIGN COPYRIGHT: MINISTRY OF EDUCATION, REPUBLIC OF THE FIJI ISLANDS

2 2. MINISTRY OF EDUCATION FIJI SCHOOL LEAVING CERTIFICATE EXAMINATION 2011 EXAMINER S REPORT TECHNICAL DRAWING AND DESIGN 1. INTRODUCTION A total of 1472 candidates registered for this examination. The marks achieved ranged from13 to 98. The questions set out in this examination was taken from the Fiji School Leaving Certificate Technical Drawing and Design Syllabus as prescribed by the Ministry of Education, Technical Vocational Education and Training Department and is assumed to be the tool used by teachers in the schools during the academic year The paper consisted of three sections - SECTION A, SECTION B and SECTION C. SECTION A (10 MARKS ) This section was compulsory and contained ten multiple choice questions. Marks ranged from 0 to 10 and most candidates scored between 2 to 7 marks. This showed a below average performance of the candidates. Candidates still lacked the understanding of the basic concepts about the various topics that they are suppose to learn during the two years in which the subject was implemented. Teachers are asked to continue to emphasise these basic concepts in Candidates need to spend time reading the questions thoroughly before making an informed decision on the correct answer. SECTION B This section has seven questions of which candidates were to answer only five questions. Each question was worth 15 marks and the nature of the questions was of problem solving type. SECTION C DESIGN This section had three questions of which candidates were to answer only one question. Most of the candidates scored 4 to 12 marks. This showed that candidates lacked understanding of designing concepts. It is strongly recommended that teachers show the basic-free hand sketching skills in designing while teaching. Candidates need a lot of practise with free-hand sketching in drawing the possible solution and the final solution.

3 3. SUMMARY OF RESULTS FSLC TECHNICAL DRAWING AND DESIGN 2011 SECTION A MULTIPLE CHOICE REPONSES TO EACH QUESTION QUESTION TOPICS COMMENTS 1 PICTORIAL DRAWING CAD A B C D CONIC SECTION A B C D DESIGN AND PROBLEM SOLVING DESIGN AND PROBLEM SOLVING 6 ELLIPSE 7 SCALES PICTORIAL 8 DRAWING 9 HELIX 10 SECTIONING A B C D A B C D A B C D A B C D A B C D A B C D A B C D A B C D Candidates were not able to differentiate between the types of pictorial Drawing. Majority answered A whereas the answer is D Candidates answered this very well. This showed that they had a sound knowledge of this topic. A well answered question showing the understanding of the Design process. This question was also answered well showing clear understanding of the design process A very small percentage of candidates managed to get this question correct showing very poor understanding of the concepts relating to the advantage of CAD Drawing Majority of the candidates managed to get this question correct. Well answered Although well answered, for those who got it wrong, their choice was A. Not answered well. Candidates did not show a good understanding of the content A well answered question indicating a good understanding of Helix. Not well answered. Showing poor knowledge on the topic.

4 4. SECTION B QUESTION 1 CONIC SECTION (15 marks) This question on basic construction of parabola was a popular choice for the candidates. PART A (10 marks) Many candidates did not draw the focal sphere and labelled the vertex, directrix and focal point incorrectly. Candidates did not draw the diagonal for the construction of the parabolic curve. It was also noted that many candidates were not able to name the curve correctly. PART B (5 marks) Many candidates used the wrong method to draw the hyperbolic curve. Some curves drawn were touching the asymptotes which was not correct. Some of the candidates did not name the curve correctly. It is important for teachers to use some practical questions after the students have gone through the theory and the basic concepts of the topic. This will link the students knowledge and understanding from the classroom to real-life situation or from abstract to concrete. QUESTION 2 2 POINT PERSPECTIVE (15 marks) This question was on basic construction of perspective drawing. From the 73% of the candidates that attempted the question, 52% scored between 8-15 marks. A number of them scored the full 15 marks. While applauding the performance of those few, it is important to relook at the reasons why a greater number of candidates are finding difficulty in solving problems of this nature. This question has been a very basic example and yet many candidates were having a lot of difficulties answering it. Most candidates managed to obtain the correct VP1 and VP2 while some guessed the position by just drawing a line to the PP. The height line was not established in most cases, this resulted in inaccuracy of true perspective drawing of the object Parallel lines from the front elevation to the height line was also ignored, candidates failed on the steps of constructing simple perspective drawings. The object contained the sloping edge, some managed to get the edge on the perspective drawing while others assumed the line as parallel to the base.

5 5. QUESTION 3 DEVELOPMENT This question was a simple development of a prism. It was a very basic example and yet many candidates had a lot of difficulties answering the question. Most of them were not able to get the projection line used in development. In most cases, candidates were not able to find the true shape. QUESTION 4 CIVIL ENGINEERING DRAWING (15 marks) Many candidates were able to use the correct scale for the load line. The scale should be an enlarging one and not a reduction scale as most candidates wrote for their scale. Most candidates did not know how to draw the polar polygon and to determine the reactions RI and Rr. Hence, they could not draw the polygon and the force diagram correctly. One area that most candidates failed to show competency in was the analysis of the nature and magnitude of the forces in each of the members stated in the question. It should be made clear to teachers and students that magnitude of the forces and senses shown on the table and stress diagram respectively cannot be correct unless the vector diagram is correctly determined. Teachers need to emphasize on the production of the vector diagram. QUESTION 5 INTERPENETRATION (15 marks) This question was poorly attempted by those candidates who opted for it. The major drawbacks in this question were the projection of the line of intersection and points on the line intersection. Candidates had difficulty in identifying the true length which were given on the base of the plan. This is determined by projecting the T.L. of the line of intersection, its point view that will also be stepped off as chords in the arc, giving the points of the three sides in the development. Most candidates could not project the right lines because the line of intersection was not correctly projected and also a problem to development of prism. The candidates will continue to find difficulty in this area if teachers do not clearly show the procedures on a step by step basis. QUESTION 6 PICTORIAL DRAWING (15 marks) This question was the second most popular choice candidates did quite well and this was an indication of the level of interest shown on the topic. Candidates had shown good visualization skills in order to correctly interpret the orthographic drawings before converting it to its pictorial form. A quick sketch would be preferable for reference.

6 6. (a) Orthographic Drawing End Elevation (3 marks) This is a shaped blocked where the End Elevation had to be drawn. About 66% of the candidates attempted this part of the question and were able to correctly interpret and draw the End Elevation. Difficulties were shown in hidden lines. Majority of the candidates failed to show the hidden lines. Teachers need to emphasize more on this. Candidates showed difficulties in the positioning of the End Elevation. Some showed confusion as it was placed beside the plan. (b) Isometric Drawing (12 marks) All of the candidates that attempted this question were able to correctly interpret the given orthographic drawing and produce the final Isometric Drawing. This was a very simple shaped block with the isometric projection partly drawn. When the term Isometric is used in a question, the candidates must understand that an Isometric scale will not be required to make the final Isometric Drawing. Majority of the candidates failed to show the Hidden Lines on the Isometric Drawing as required by the question. Students need to read and interpret the question well before attempting it. Teachers need to put more focus on this. Overall performance this section was rated as above average. The use of the crate in pictorial drawing is vital because it eases the whole process. This is irrespective of the type of pictorial required, whether it is Isometric, Perspective or Oblique. The technical skill of those few candidates to produce the required view is very much appreciated and is an indication of the power of visualization in converting 2-D to 3-D correctly. QUESTION 7 ENGINEERING DRAWING (15 marks) This question was the least popular choice. The total marks attained by candidates that attempted the question ranged from 0 to 10 marks with only a mere 15% pass rate. This is a clear indication of how the topic has been taught in school together with the level of commitment from the teachers in the teaching of the content. Below is a detailed analysis of the various parts of the question as attempted by the candidates.

7 7. PART A SECTIONAL ELEVATION ASSEMBLED (10 marks) Orthographic drawing Many candidates continued to redraw the views pictorially, The skills to convert from pictorial projection (3D Isometric) to orthographic projection (2D) was lacking. The dimensions were clearly shown on the exploded isometric drawings which were not correctly interpreted by candidates. There was very little knowledge on how to assemble components in an orthographic drawing. This area needs a lot of attention and clarification from teachers. Similarly, the conventions for drawing the nut and bolt, external and internal threads were not well understood by most candidates. The teachers are once again advised to stress the importance of drawing these engineering fasteners in orthographic. Sectional Elevation Most candidates did not realize that the elevation needed to be sectioned and in most cases there were no cross hatching lines drawn. Candidates also have lesser understanding of components that do not need cross hatching lines after being sectioned e.g. in this question there was a pin, and nut & bolt which should have been shown only with outside views. The exercise actually took a lot time to answer because of the skills of having to convert from pictorial to orthographic and simultaneously assembling the pieces together and then sectioned. It is felt that students need to do a lot of practise in this area for a better performance in the future and teachers need to provide this platform for the students in the classroom. Overall performance A majority of the candidates (78%) scored between 0 to 4 marks and is comparative with the comments stated above. Only 20% of the candidates scored between 5 to 7 marks while 2% scored between 8 to 10 marks for this question. The analysis clearly indicates the level at which the content has been dealt with in the schools and is a reminder to teachers to put more emphasis on this during classroom teaching. PART B END ELEVATION (5 marks) Orthographic drawing Many candidates continued to redraw the views pictorially. The skills to convert from pictorial projection (3D isometric) to orthographic projection (2D). The dimensions were clearly shown on the exploded isometric drawings which were not correctly interpreted by candidates.

8 8. There was very little knowledge on how to assemble components in orthographic drawing. This area needs a lot of attention and clarification from teachers. Similarly, the conventions for drawing the nut and bolts, external and internal threads were not well understood by most candidates. The teachers are once again advised to stress the importance of drawing these engineering fasteners in orthographic. Nut & Bolt Candidates should have seen that there were three flat faces of the hexagonal nut & bolt in the elevation and only two in the end elevation. The component was not correctly positioned in the orthographic view this showed that there was lack of emphasis on this skill during interaction in the classroom. Overall performance A majority of the candidates (71%) scored between 0 to 2 marks which is a very low performance from the candidates. Only 29% scored between 3 to 5 marks. The teachers are reminded to ensure that the contents are thoroughly taught so that the questions posed are meaningful to the candidates and they should provide the correct responses accordingly. The overall pass rate (15%) is indicative of the thrust put in by the teachers in the teaching of the content. It will be a great joy to see improvement in the performance of candidates in this particular topic. SECTION C DESIGN A majority of the candidates attempted Question 3 in this section and scored between 5 to12 marks. GENERAL COMMENTS (a) Possible solution 1 and 2 The spaces given were enough for the candidates to draw the free hand sketch of the designs. Majority of the candidates lacked the skill in free-hand sketching and they drew very small drawing. For possible solutions teachers should place emphasis on the following: free hand drawing pictorial drawing adherence to the specification proportionality of the drawing outlook of the structure quality of the pencil work

9 9. (b) (i) Candidates answered this section very poorly where they indicated simple construction. It is strongly recommended for teachers to specify on: the specification of the construction if it can be welded or nailed bolts and nuts can that be used simple joint construction assembling method and dismantle if needed types of material used (ii) It showed that majority of the candidates lacked the understanding of this word Aesthetics and they were not able to answer the question. Teachers need to explain the meaning of the word to their students. This includes: colours shapes functionality type of Finishing used attractiveness in the market (c) Final solution Pencil Rendered or coloured Majority of the candidates were able to draw the final solution well but they needed to in co-operate the ideas from the possible solution to the final solution. Teachers needed to consider this in the final solution to be in pictorial proportional aesthetic appearance incorporating ideas from possible solution rendering meeting the specification guide lines quality of the drawing GENERAL COMMENTS 1. It is encouraging to note that candidates have demonstrated high level of drawing skills with some showing exceptional skills and accuracy. 2. There is still a lacked of knowledge on some basic concepts thus limiting the ability of the candidates to proceed through the question. 3. Time management is of concern as some candidates could not finish the paper. 4. Many candidates failed to read instructions thereby attempting all the seven questions.

10 10. FSLC TECHNICAL DRAWING- MARKING CRITERIA QUESTION MARKING CRITERIA MARK ALLOCATION 1 Conic Section a Construction of focal sphere 1 Label the vertex focus,and Directrix 3 Drawing the Axis and the projection line 2 Marking the digonal 1 Plotting the points 1 Drawing the curves 1 Name the Section 1 Asymptotes b Division of parallel and diagonals 2 Plotting of points 2 Name the Curve 1 2 Perspective Drawing Getting VP! andvp2 on eye level 2 Projection line from SP to Plan 1 Height line 1 Projection line From Elevation 1 Projection line from VPI and VP2 To 2 height line Getting the faces of the shape correctly 8 3 Development of shapes All projection lines 1 Development of shapes 6 Labelling the points 3 True shape 4 Neatness 1 4 Civil Engineering Drawing the Load Line 1 Determine the correct scale 2 Drawing the polar diagram 3 Drawing the link polygon 1 Drawing the CLOSER 4 5 Drawing the force diagram 2 Magnitude of RL and RR 2 Projections lines from plan and elevation 1

11 11. Drawing of end elevation 3 Complete the plan 2 Development of triangular pyramid 3 Development of square prism 3 Plotting of points 2 labeling 1 6 Isometric Drawing Projection line Plan and end elevation 1 Drawing of End Elevation 2 Drawing the isometric crate 2 Slopping edges 2 Shape of the isometric block with hidden 6 lines Drawing the faces 2 7 Engineering Drawing Section A-A Assembled view layout 4 Each component assembled correctly 3 Sectioned lines 1 3flats hexagonal nut shown 2 End Elevation Components assembled correctly 2 Dimension correct 2 All components aligned 1 (b) (i) construction The specification of the construction It can be welded or nailing Bolts and nuts can be used Simple joint construction Assembling method and dismantle if needed Types of material used (ii) Aesthetic Colour Shape Functionality Finishing used Attractive in the market

12 12. to be in pictorial Proportional Aesthetic appearance Incorporating ideas from possible solution Rendering Meeting the specification guide lines Quality of the drawing (b) (i) construction The specification of the construction It can be welded or nailing Bolts and nuts can be used Simple joint construction Assembling method and dismantle if needed Types of material used (ii) Aesthetic Colour Shape Functionality Finishing used Attractive in the market to be in pictorial Proportional Aesthetic appearance Incorporating ideas from possible solution Rendering Meeting the specification guide lines Quality of the drawing (b) (i) construction The specification of the construction It can be welded or nailing Bolts and nuts can be used Simple joint construction Assembling method and dismantle if needed Types of material used

13 13. (ii) Aesthetic Colour Shape Functionality Finishing used Attractive in the market to be in pictorial Proportional Aesthetic appearance Incorporating ideas from possible solution Rendering Meeting the specification guide lines Quality of the drawing THE END

C A R I B B E A N E X A M I N A T I O N S C O U N C I L REPORT ON CANDIDATES WORK IN THE SECONDARY EDUCATION CERTIFICATE EXAMINATION MAY/JUNE 2010

C A R I B B E A N E X A M I N A T I O N S C O U N C I L REPORT ON CANDIDATES WORK IN THE SECONDARY EDUCATION CERTIFICATE EXAMINATION MAY/JUNE 2010 TECHNICAL DRAWING GENERAL PROFICIENCY Copyright 2010 Caribbean