REPORT. Misconception: most of the candidates gave any plastic they know.

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1 REPORT GENERAL OVERVIEW The question paper consisted of 16 questions of which 10 were short general questions which were compulsory and formed part A. Part B was in two sections, section1 consisted of three questions based on tools and materials and the candidates were to choose any two as they carried equal marks. Section two also had three questions based on workshop processes; from which, candidates were to choose two questions. QUESTION 1 This provided candidates with two plastic items (a) Electrical conduits (b) Tooth brush bristles Candidates were to name suitable plastic for each item Expected responses (a) P.V.C (UPVC) (b) Nylon Misconception: most of the candidates gave any plastic they know. QUESTION 2 The question required the candidates to name the part of a try square which is used to test for flatness Back part of the blade. Almost all the candidates gave the correct answer 1

2 QUESTION 3 The question showed a sketch of a process of drilling using pedestal drilling machine a) The question required the candidates to name the process and give a possible hazard. b) To give two safety measures required when the process is carried out. a) Almost all the candidates gave the correct answers b) Almost all the candidates gave the correct answers QUESTION 4 The question required three reasons why the stock of a marking out tool is run against the face side or face edge. EXPECTED RESPONSE The sides are flat, square and straight CANDIDATES RESPONSE Some gave the use of a tool e.g the try square is used to test for squareness, flatness and mark lines at right angles to the true edge. QUESTION 5 Candidates were given a sketch of a marking out tool (mortise gauge) with the parts labeled X and Y. a) Name the tool and state its use. 2

3 b) State a specific material for parts X and Y. EXPECTED RESPONSE a) Mortise gauge: used to mark two parallel lines to a true edge. b) X = plastic, brass, box wood Y= steel (mild steel) a) The correct tool was given, but the use was of a marking gauge. b) Some named the parts, some gave any material they know, some confused Y with X QUESTION 6 The question required the meaning of the term anthropometric EXPECTED RESPONSE Study of human being size in relation to the environment Most of the candidates did not attempt the question at all. Some given answers were not relevant to the question at all e.g explanation of any process. QUESTION 7 The question showed a cutting tool (circular split die). It required candidates to: a) Name the tool and state its use. b) Identify two possible problems that could occur when using the tool. a) Circular split die : for cutting external threads. b) Cutting threads at an angle, broken threads due to lack of lubrication, material twisting 3

4 a) Few got it correct, whereas most of them just wrote: die, split die, tap e.t.c b) Almost all the candidates gave wrong response e.g safety measures, problem with other workshop tools or processes which were not related to the given tool. QUESTION 8 To state three problems associated with poorly seasoned timber. EXPECTED RESPONSE Heavy, hard to work on, easily attacked by insects and fungi, does not take finishes well, promotes rust in metal fasteners, increase defects (split, twist, warp, cup, decay). CANDIDATES RESPONSE Almost all candidates gave the correct responses. QUESTION 9 Showed a sketch of a frying pan. It then required candidates to: a) give a suitable material for the handle b) give two properties that make the material in (a) suitable for the handle a) Bakelite, wood b) Heat resistant/poor conductor of heat, strong stiff and hard etc 4

5 a) Some candidates gave materials which were not specific for the handle of a frying pan e.g metal plastic, copper etc. b) Most candidates gave the correct responses. QUESTION 10 To state two advantages of using a sliding bevel instead of using a meter square. Set to any angle, mark any, angle, blade length easily adjusted, easy to use etc. Most of the candidates gave the correct responses. PART B SECTION 1 QUESTION 11 (a) To state one physical property and one use for each of the materials. (i) Acrylic (ii) Aluminium (iii) Chip board Two woodworking tools shown (P= carpenters mallet, Q=try square) (b) (i) To name each uses of each tool (ii) To state two uses of each tool (c) (i) To sketch a tool used together with tool P (ii) To show how tool Q is tested for accuracy 5

6 (a) (i) Rigid, hard wearing, does not shatter, colored etc Use: car rear light covers, sign posts, air crafts canopies e.t.c (ii) Light in weight, less corrosive, ductile, easily machined e.t.c Use: kitchen utensils, parts of aircrafts, doors and window frames, TV aerials e.t.c (iv) Strong in all directions, porous, easily finished, easily machined e.t.c (v) Use: cabinet making, partitioning, ceiling (b) (i) P = carpenter s mallet/woodworker s mallet Q = Try square (ii) Uses: P= driving chisels, knocking joints in and out Q= Testing squareness, marking lines at right angle to a true edge, checking for flatness. (c) (i) The sketch of a chisel (ii) The sketch of a try square on square piece turned back to front (a) (i) Most gave the correct response (ii) Most gave the correct response (iii) Most gave wrong property and correct use b) (i) P = Most gave the name as wood mallet which is incorrect Q = Most gave the correct response (ii) P = Most gave only one use which was correct Q = Most gave one use which was correct 6

7 c) (i) Most made a correct sketch (ii) Most gave the tool in use not to test the tool. Some gave the wrong method of testing e.g by using steel rule, protractors, set square e.t.c QUESTION 12 Two sketches of hand tools were given (R = odd led calipers labeled X on the joint, 5 = Smoothing plane ) a) (i) To name the tools R and S (ii) To state the use of each tool (iii) To name the part labeled X on tool R b) With notes and sketches to show how tool R is set to 25mm c) With notes and sketches to show the purpose of the cap iron on tool 5 and how it is held to the blade a) (i) R = odd leg calipers S=SMOOTHING PLANE (ii) R=marking lines parallel to a true edge S=making fine surface or finishing end grains (iii) Rivet b) Rule edge against the odd leg, the scribes to point at 25mm on the rule. c) Cap iron and blade, screw holding cap iron and blade. Cap iron curved to curl the shavings to avoid splitting or digging of the blade. (a) (i) Most of the candidates gave the correct responses. 7

8 (ii) Most of the candidates gave the correct use of odd leg calipers, while on smoothing plane they gave the use of a Jack plane e.g to plane to the gauge line, to flatten the surface. (iii) Most of the candidates did not know the part X at all. (b) Most of the candidates did not place the rule edge against the odd leg edge, while others did not point at 25mm on the rule. (c) Almost all the candidates showed the use of a smoothing plane not the use of the cap iron. QUESTION 13 a) To state three different forms of plastics and give one example of each. b) To sketch a pictorial view of the following manufactured boards clearly showing the edge view. (i) Block board (ii) Plywood (3ply) (d) To state the importance of the following properties shown in metal workshop processes. (i) Fusibility (ii) Elasticity (iii) Malleability EXPECTED RESPONSE A) FORM EXAMPLE Powder Sheet Granules Liquid Paste Rod polythene Acrylic Polystyrene PVC Polyester resin Nylon/polypropylene 8

9 Tube Nylon b) (i) Clear sketch of block board Ends in front (ii) Clear sketch of 3ply two edges shown c) (i) Fusibility help metal to be worked in a molten state to form different shapes and forming new materials e.g melting solder to a joint. (ii) Elasticity to help materials to stretch and perform different duties and come to its original size e.g spring for shock absorption. (iii) Malleability: It allows for formation of different items through rolling and hammering of steel eg shaped burglar proofing. (a) Some candidates gave the correct responses while others gave the types of plastics e.g thermo plastics or thermosetting plastics. (b) (i) Most of the candidates made the correct sketches but a few of them did not show proper arrangements of pieces and grains. (ii) Most of the candidates made the correct sketches, but some did not show the crossing of the veneers. (c) (i) Most of the candidates did not know what fusibility is e.g they explained the methods of joining metal. (ii) Most of the candidates gave the definition not the importance (iii) Most of the candidates gave the definition not the importance. 9

10 QUESTION 14 The sketch of a trophy was shown (a) (i) To name a suitable material for making the trophy. (ii)to give two reasons why sand casting is used to make the trophy. (b) Using notes and sketches to explain the process of sand casting the trophy. (c) To state two safety precautions to be observed during sand casting and explaining how to solve each problem. (a) (i) Aluminium, Pewter, zinc, lead, tin (metals with low melting point) plastic. (ii) Low cost, complex shape can easily be done in school workshop. (b) The sketch of cope and drag with sand Pattern: molten metal/plastic is poured into a sand mould etc Sketches: Boxes (drag and cope with runner and riser) pattern (c) (i) Use leather cloths hold the mould using tongs, pouring to be done at lower level, short distance between oven/hearth and the drag etc (ii) Molten material solidifying before filling the pattern Material weak in flowing, air tapped in the molten material, existence of impurities. (13) Solutions Short distance between the oven and box Material should be heated to the correct temperature Constant flow of material to the mould Clean the sand before molding 10

11 (a)(i) Most of the candidates gave the correct responses (ii) Most of the candidates gave the correct responses (b) Most of the candidates explained different processes which were not sand casting. (c) (i) Most of the candidates gave correct responses. (ii) Most of the candidates mentioned the safety precautions not the problems of sand casting. QUESTION 15 The sketch of a dripping tray for a geyser was shown. (a) To state a suitable material for the tray. (b) To use notes and sketches to describe the manufacturing of the tray using the material selected in (a). (c) (i) To use notes and sketches to describe how the outlet on the tray can be made and the drainage pipe fixed. (ii) To use notes and sketches to describe how the tray can be held in position. (a) Non corrosive material: copper, polythene (ld), Perspex, Aluminium, gal vanished sheet metal etc. (b) Handmade (using tools) Marking out (correct tools) Cutting out (correct tools) Bending and joining (correct tools and methods) Holding devices PROCESSES Vaccuum forming, moulding Heat to soften the material 11

12 Create a vacuum/pressing To cool Remove the mould etc (c) (i) Mark to locate the hole, drill, fixing, soldering, brazing, tensol cement, taping and threading. (ii) Making brackets and suspend. Making a stand etc (ii) (a) Most of the candidates gave the correct material except a few who gave wood as the answer. (b) Most of the candidates gave correct steps when producing the tray except the joining part where they used rivers. (c) (i) Most candidates showed how to drill and showed the pipe fixed but they did not show how to fix the drainage pipe to the outlet. Most candidates did not know the dripping tray and its use hence why they even drew a serving tray with handles and not show the appropriate method of holding it in position. QUESTION 16 The outline sketch of a toilet roll holder was given with some parts labeled e.g back, sides and roller holder a) (i) To give three properties of a material suitable for making the toilet roll holder (ii) For each property in (a) (i) to give one reason why the property is suitable. b) (i) If the toilet roll holder was made from 10mm thick wood, to use notes and sketches to design the appropriate joint between the back and the sides. 12

13 (ii) To use notes and sketches to describe how the curves on the sides are cut (c) To use notes and sketches to describe how the holder will be temporarily removed to insert the roll. a) (ii) light in weight, water resistant, tough, easy to clean, non toxic etc. (ii) To mount on wall, to use around damp area, long lasting. b) (i) wood joint (e.g bare face mortice and tenon joint, dovetail, box pin and other appropriate joint. (ii) Cutting the curve with coping saw finish with spoke shave, files or rasp Method of holding c) Slotted sides/ spring loaded holder, lifted up a) (i) Most candidates gave the correct properties of the material required. (ii) Most of the candidates did not match well the properties with suitability. b) (i) Most of the candidates made the appropriate joint for the back and the side except that the quality of their sketches was not good. (ii) Most of the candidates used the correct tool for cutting the curves, but they did not show the method of holding the piece while being cut. c) Most of the candidates showed that the roller holder can be lifted up, while a few said it can be pulled on the sides. 13