Woodwork Paper 1 Questions and Answers - KCSE 2021 Past Papers

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SECTION A (40 marks)
Answer all the questions in this section in the spaces provided.

1. List four functional requirements of a woodwork workshop. (2 marks)
2. State three causes of accidents relating to the use of hand tools in a woodwork workshop. (3 marks)
Explain the cause of each of the following classes of fire:
1. Class A fire (2 marks)
2. Class B fire (2 marks)
Figure 1 shows a vernier calliper reading. (2 marks)

Determine the value of the reading.
State four practices that demonstrate the proper use of a cross-cut saw when cutting timber. (4 marks)
1. State two functions of the knob on a bench plane. (2 marks)
2. Sketch the plan of the head to show the shape of the slots on the following types of screws:
  1. Philips recess (2 marks)
  2. Allen recess (2 marks)
1. Sketch and label a try square. (2 marks)
2. State two uses of a try square. (2 marks)
Figure 2 shows the cutting edge of a chisel.
1. Name the angles labelled a and b. (1 mark)
2. Give the recommended value for each of the angles in 7(a). (2 marks)
Sketch each of the following types of treatment given to the edges of tables: (3 marks)
1. Chamfer
2. Ogee
State four characteristics of varnish applied on a dry wooden surface. (4 marks)
Print the phrase "Practice makes perfect" using the vertical capital letters of uniform 5 mm height and word spacing of 5 mm. (5 marks)

SECTION B (60 Marks)
Answer question II on A3 paper and any other three questions from this section in the spaces provided. Candidates are advised not to spend more than 25 minutes on question 11.

Figure 3 shows a machine drawn in isometric projection.

Draw the following views of the component Full Size in first angle projection: (15 marks)
1. Sectional front elevation along the cutting plane X-X.
2. Sectional plan along the cutting plane Y-Y.
1. State four factors to consider when choosing a finish for a wooden item. (4 marks)
2. Outline the procedure of measuring, marking and fitting a mortise lock on a kitchen cabinet door. (11 marks)
1. State three advantages of plain sawn timber over quarter sawn timber. (3 marks)
2. Figure 4 shows the plan of a curved timber piece.
  
  With the aid of a sketch, outline the procedure of kerf bending to produce the curved piece. (12 marks)
1. State two functions of the cap iron in a jack plane. (2 marks)
2. Figure 5 shows a wooden block with a groove 12 mm wide and 20 mm deep.
  
  Outline the procedure of marking and cutting the groove using a rebate plane. (7 marks)
3. Explain two methods of testing a planed timber face for straightness and flatness. (6 marks)
1. State two uses of a nail punch. (2 marks)
2. Outline the procedure of sharpening a chisel using an oilstone. (5 marks)
3. Describe the following natural adhesives, giving one characteristic of each:
  1. Animal glue (3 marks)
  2. Case-in (3 marks)
  3. Blood glue (2 marks)

MARKING SCHEME

NO	DESCRIPTION	MARKS
	SECTION A
1	Functional requirements of a wood workshop Ventilation Lighting (natural and artificial) Adequate headroom Doors opening outward At least two doors on opposite sides Storage space Any 4x 1⁄2 Causes of accidents related to use of hand tools: knocks on hands Knock on hands injuries due to the tools dropping and hurting the legs or feet injuries due to waste from materials flying into the eyes carelessness failure to use the appropriate tool for a particular task Any 3 x 1 Accept any other correct response	2 marks 3 marks
2	Classes of fire Class A: They are caused when solid, organic materials such as wood, cloth or rubber become heated, ignite and undergo combustion. There are the most common type of fire. Class B: They are caused by flammable, combustible liquid and gases. Such substances include petrol, thinners, alcohol etc. 2 x 2	4 marks
3	Vernier Caliper reading Steel rule reading: 4 main units - 4 x 10 = 40.00 mm 1⁄2 2 sub units 2 = 2.00 mm 1⁄2 1 intermediate 1 x 0.25 = 0.25 mm /1⁄2 Vernier scale reading: 11 units = 0.11 1⁄2 Total = 42.36 mm = 4.236 cm	2 marks
4	Practices that demonstrate proper use of cross-cut saws: Place the thumb against the side of the saw blade when starting the cut. Start the cut by drawing the saw back a few inches of teeth a few times Keep the saw blade at right angles to the work surface. Saw only on the downwards stroke applying pressure evenly Do not force the saw if it binds When nearing the end of the cut, hold the waste side of the wood to prevent the board breaking off unevenly Any 4 x 1	4 marks
5	Functions of the knob in a bench plane: To help apply pressure on the plane when starting to plane To guide or steer the plane when moving it forward To lift the plane during the finishing of planning. Any 2 x 1 Types of slots on wood screws: Philips recess Allen recess 2 x 2	2 marks 4 marks
6	Try square Uses of a try square Checking for flatness Checking for squareness (90° at the corners) Marking out on pieces of wood Any 2 x 1	2 marks 2 marks
7	Cutting edge of a chisel: Grinding angle Sharpening angle 2 x ½ 25° 30° 2 x 1	1 mark 2 marks
8	Sketches of edge treatment to table edges: 2 x 1½marks	3 marks
9	Characteristics of varnish: Resistance to heat, wear, solvents, acids and alkalis Resistance to water and water vapour exchange Easy to clean the surface Any 4 x 1	4 marks
10		5 marks
	SECTION B
11	SECTION Y-Y Correct scale used = 2 Section x-x Correct section (2 parts x1) = 2 Hatching (2 parts x1) = 2 Section y-y Correct section (2 parts x1)=2 Hatching (2 parts x1) = 2 Accuracy = 2 Line work = 1 Neatness = 2 = 15 marks Accept if the solution is drawn with a through hole.	15 marks
12	Factors to consider when choosing a finish for a wooden item: Bleaching Durability Protection Ease of application Appearance Reversibility Safety Ease of rubbing/cleaning Cost Any 4 x 1 Procedure of measuring, making and fitting a mortise lock on a cabinet Measure the required height from the top or bottom of the position of the spindle. Square the level round the edge of the cabinet Measure the lock from the outer edge of the face to the centre of the spindle hole and mark this on both faces of the cabinet Measure the lock vertically from the centre of the spindle hole to the top centre and bottom centre of keyhole and mark the centres on both faces of then/ Hold the lock against the door, sight through the spindle hole to line it up with the spindle cross mark and then mark lightly around the outer edge of the lock Square this outline across the edge of the cabinet Using a mortise gauge, mark the thickness of the lock and bolt on the edge of the cabinet Drill the holes for the spindle and keyholes Drill a series of holes for the lock mortice and clean out with a beveled firmer chisel. Complete the key hole with a pad saw Pit the lock in the mortice, adjust accordingly and screw into position. 11x1	4 marks 11 Marks
13
	Advantages of plain sawn timber over quarter sawn timber It costs less because it is easy to saw Figure patterns resulting from annual rings are more conspicuous It is less susceptible to defects in drying. Has minimum wastage Any 3 x 1 Kerf method of producing curved piece of timber. Select the piece if timber Determine the radius of curvature Determine saw cut positions Mark the positon of saw cuts Cut on the marked positions Set the jig to the required curvature Insert the timber Apply glue to the kerfs Clamp the timber piece to the jig and let dry Any Any 8x1	3 marks 4 marks 8 marks
14	Functions of a cap iron on a jack plane: To break and curl the wood shavings To stiffen the cutting iron To strengthen the blade of plate Any 2 x 1 Set the mortice gauge to the required size. Mark the width of the groove needed. Mark the depth of the groove Set the plough plane to the required width and depth Clamp the piece on the bench vice in order to be steady Make light cuts along the grains of the work piece Make continuous cuts until you attain the required groove depth. Remove the chaff from the groove to the required depth 7 x 1 Methods of testing a planed timber face for accuracy. Using winding sticks (winders) Two short parallel lengths of timber are used simultaneously. Each wind stick is laid across the timber workpiece near each end. The taps of the winders are sighted and any irregularities noted are corrected. One winder may be moved along the length of the board to test intermediate sections. Using a straight edge A long piece of squared timber or other edge is used to check that the face is straight from end to end. It is also usually placed diagonally and viewed against a source of light. Any irregularities are corrected using a smoothing plane. Using a try square Hold the timber piece up to the light and put the try square along the length of the face. The edge of the try square blade may also be held across the work piece to check flatness. Any 2x3	2 marks 7 marks 6 marks
15	Uses of a nail punch: To sink the heads of nails or pins below the surface of timber when the holes are to be filled. Assist in driving nails into awkward positions Used when avoiding bruising the surface of timber with a hammer. Any 2x1 Procedure of sharpening a chisel using an oil stone. Apply enough oil onto the surface of the stone Hold the chisel comfortably with both hands at an angle of approximately 30° Move the tool back and forth in even motions until a honed edge is obtained Reverse the cutter to lay flat on the oilstone and rub up and down to remove any burr Draw the cutter across a piece of waste wood to remove any remaining burrs. 5x1 Animal glue: It is made from hides and bones of animals by boiling them after purification. Characteristics: It is very strong It cures at room temperature 3x1 Casein glue: Made by dissolving casein, a protein obtained from milk in aqueous alkaline solvent. Characteristics: It is used at room temperature It sets and hardens by loss of water (to the wood substance). 3x1 Blood glue/Albumin glue: It is made by extracting albumin protein from animal blood and drying it to powder which is remixed with water for use It is resistant to moisture though not waterproof 2x1	2marks 5 marks 3 marks 3 marks 2 marks