Cambridge Syllabus Notes

Resistant Materials – Tools, Equipment & Processes

Learning Objective

Identify, describe and select appropriate hand tools, power tools, machine tools and shaping processes for the manufacture of resistant‑material components, and apply safe working practices and accurate measurement techniques (AO1‑AO3).

1. Material Families (including woods)

For each family the table lists the key mechanical/physical properties required by the Cambridge IGCSE 0445 syllabus, typical uses and processing considerations.

Material Family	Key Properties (syllabus focus)	Typical Uses	Processing Considerations
Ferrous Metals (e.g., mild steel, stainless steel)	High tensile & compressive strength Good ductility (except some stainless grades) Magnetic (except most stainless) Conducts heat & electricity	Structural frames, brackets, fasteners, gears	Cut with hacksaw, band‑saw or plasma; weldable; machinable; requires deburring after cutting.
Non‑ferrous Metals (e.g., aluminium, copper, brass)	Low density (lightweight) Excellent corrosion resistance (especially aluminium, copper alloys) Non‑magnetic High thermal conductivity	Aerospace components, heat sinks, decorative fittings	Machinable; avoid excessive heat when drilling; can be anodised, plated or painted.
Thermoplastic Plastics (e.g., PVC, acrylic, polycarbonate)	Defined softening/melting point Good impact resistance Can be reheated & reshaped	Electrical housings, protective screens, consumer goods	Cut with fine‑toothed saws or laser; drill with HSS bits at low speed; risk of melting – use coolant or low RPM.
Thermoset Plastics (e.g., phenolic, epoxy resin)	Hard and rigid after cure Heat‑resistant, do not melt High dimensional stability	Insulators, circuit boards, composite laminates	Machining requires carbide tools; avoid high temperatures; usually supplied pre‑formed.
Composites (e.g., carbon‑fiber reinforced polymer, glass‑fiber)	Very high strength‑to‑weight ratio Anisotropic – properties differ with fibre direction Corrosion‑resistant	Aerospace panels, sports equipment, automotive parts	Cut with abrasive wheels or CNC; sand with fine grit; avoid delamination – cut perpendicular to fibres where possible.
Smart Materials (e.g., shape‑memory alloys, piezo‑ceramics)	Change shape or properties in response to temperature, electric field, stress, etc. High functional performance but limited structural strength	Actuators, sensors, adaptive structures	Handle according to manufacturer guidelines; specific heat‑treatment or voltage limits must be observed.
Woods (natural timbers, plywood, MDF, particle board)	Variable tensile & compressive strength (depends on species & grain) Good workability, low density Moisture‑dependent – may swell/shrink Generally non‑conductive	Furniture, prototypes, decorative panels, jigs	Cut with saws, hand tools or CNC; sand to finish; protect from moisture; use appropriate dust extraction.

2. General Safety Overview

Wear appropriate PPE: safety glasses, hearing protection, gloves (where appropriate), dust mask or respirator for fine particles.
Ensure tools are in good condition; guards and safety switches must be functional.
Maintain a clean, well‑ventilated work area; dispose of waste material according to school policy.
Never operate a tool while fatigued or under the influence of alcohol/drugs.

3. Hand Tools

Manually operated tools used for preparation, finishing and small‑scale shaping.

Files & Rasps – Remove small amounts of material; finish edges. Types: flat, round, half‑round, triangular, wood rasps.
Hacksaws – Cut metal, plastic, thin wood or board. Choose blade tooth count: fine (24‑32 tpi) for thin metal, coarse (12‑18 tpi) for wood/board.
Hand Drills (Brace & Bit) – Suitable for softer metals, wood and plastics. Use twist bits for metal, spade or auger bits for wood.
Snips & Shears – Straight‑cut, aviation and tin snips for sheet metal; hand shears for thin plastics and sheet‑metal work.
Marking & Layout Tools – Scribe, centre punch, marking gauge, combination square, dividers.
Measuring Tools – Ruler, steel tape, vernier/digital calipers, depth gauge, micrometre.
Clamping & Securing – C‑clamps, bench vises, spring clamps, wood blocks.

4. Power Tools

Electrically or battery‑driven tools that increase speed and efficiency. Always check guards, use the correct accessory and disconnect power before changing bits.

Power Tool	Primary Use	Typical Materials	Key Safety Considerations
Electric Drill / Impact Driver	Drilling, driving screws, spot‑drilling	Metal, wood, plastics	Secure workpiece, select correct bit, keep hands clear of chuck, use variable speed
Angle Grinder	Cutting, grinding, sanding, deburring	Metal, stone, composites	Use guard, wear face shield, avoid kick‑back, wear hearing protection
Jigsaw	Curved or irregular cuts in sheet material	Wood, thin metal, plastics	Clamp workpiece, use appropriate blade, keep blade straight, wear eye protection
Rotary Tool (e.g., Dremel)	Detail work – sanding, polishing, engraving, drilling small holes	Metal, wood, plastics, ceramics	Use low speed for delicate work, wear eye protection, keep tool tip away from skin
Band Saw (Portable or Bench)	Straight cuts, resawing, cutting large sheets	Metal, wood, plastics	Use blade guard, keep fingers clear, use push sticks for small pieces, wear hearing protection
Bench‑Top Shear	Straight cuts in sheet metal up to 6 mm	Cold‑rolled steel, aluminium, thin brass	Secure sheet, wear gloves, keep hands away from blade

5. Machine Tools

Stationary equipment that provides precise, repeatable operations. All machine tools require a dedicated work area, proper grounding and routine maintenance.

5.1 Lathe

Function: Rotates workpiece for turning, facing, drilling, threading and boring.
Key Components: Headstock (spindle, speed control), tail‑stock (centre, live centre), carriage (cross‑slide, tool post), coolant system.
Typical Operations: Cylindrical turning, taper turning, chamfering, internal/external threading.
Cutting Speed (N): \(N = \dfrac{1000 V}{\pi D}\) where \(V\) = cutting speed (m min⁻¹) and \(D\) = diameter (mm).
Safety: Secure workpiece with chuck or collet, keep hands away from rotating parts, use tool‑post guard, wear safety glasses.

5.2 Milling Machine

Function: Rotating cutter removes material from a stationary workpiece.
Types: Vertical, horizontal, CNC.
Common Operations: Slotting, contouring, face milling, drilling, tapping.
Key Features: Column, table with T‑slots, spindle, speed selector, coolant.
Safety: Clamp or vise workpiece, check cutter sharpness, wear hearing protection, keep loose clothing away.

5.3 Drill Press

Function: Accurate vertical drilling with adjustable speed and depth.
Features: Column, table, spindle, speed selector, depth stop, chuck.
Typical Uses: Drilling precise holes, reaming, tapping, spot‑drilling for alignment.
Safety: Clamp workpiece, keep workpiece below table, wear safety glasses, use appropriate drill speed.

5.4 Bench‑Top Band Saw

Function: Continuous looped blade cuts irregular shapes, resaws stock, and makes straight cuts in thick material.
Suitable Materials: Metal sheets, timber, plastics up to 30 mm thick.
Safety: Blade guard engaged, fingers clear of blade path, use push sticks for narrow pieces, wear hearing protection.

5.5 Additional Machine Tools (Brief Overview)

Planer / Thicknesser: Reduces thickness of sheet material, ensures parallel faces.
Press Brake: Bends sheet metal to precise angles; uses dies and punches.
Surface Grinder: Provides high‑quality flat surfaces; uses abrasive wheels.
CNC Router / Milling Centre: Computer‑controlled multi‑axis machining for complex geometries.

6. Preparation of Materials

Raw stock must be prepared to a known datum, cleaned and securely fixed before any shaping operation.

Identify Market Form: Bar, rod, tube, sheet, plate, extrusion, profile, timber board, plywood, MDF.
Cut to Approximate Size (if required): Use appropriate hand cutting tool – hacksaw for metal, hand saw or portable band‑saw for wood/plastics. This step is part of preparation, not final shaping.
Deburring & Cleaning: Remove flash, burrs, rust or oil with files, sandpaper, abrasive wheels or solvent wipes.
Safety Considerations for Material Preparation:
- Wear safety glasses and gloves when cutting or deburring.
- For resin‑based composites or thermosets, work in a well‑ventilated area and wear a particulate respirator.
- When cutting metal, use low‑speed cuts to minimise sparks; keep a fire‑extinguisher nearby.
- Dust from wood or MDF should be collected with a dust extraction system; avoid inhalation.
- Dispose of waste (metal shavings, plastic off‑cuts, composite dust) according to school waste‑management procedures.
Mark‑out Datum Surfaces: Place the workpiece on a surface plate or a flat reference, use a carbide scribe to establish a primary datum line or plane.
Clamping & Fixturing: Choose a method that prevents movement: bench vise, C‑clamps, magnetic base (for ferrous stock), vacuum table (for sheet plastics), or custom jigs.

7. Measuring, Marking‑out & Testing

Accurate measurement underpins good design and production. The following workflow shows how the tools are used in sequence.

7.1 Measuring Instruments

Instrument	Typical Range	Resolution	Best Use
Steel Ruler / Tape	0–300 mm / 0–5 m	0.5 mm	General layout, long dimensions
Vernier / Digital Calipers	0–150 mm	0.02 mm (vernier) / 0.01 mm (digital)	External dimensions, internal diameters, step‑depths
Micrometre	0–25 mm	0.001 mm	High‑precision thickness, small diameters
Depth Gauge	0–150 mm	0.1 mm	Measuring recesses, hole depths
Set Squares & Combination Squares	0–300 mm	0.5 mm	Checking right angles, marking 45° lines
Dividers	0–200 mm	0.5 mm	Transferring distances, laying out circles

7.2 Step‑by‑Step Mark‑out & Verification Workflow

Establish a datum surface using a surface plate and a carbide scribe.
Mark reference lines with a combination square or marking gauge from the datum.
Transfer dimensions using dividers or a centre punch for hole locations.
Check critical dimensions with vernier/digital calipers or a micrometre before machining.
Adjust the layout if measurements fall outside the acceptable tolerance (see §7.3).
Secure the workpiece in the chosen clamp/fixture, ensuring the datum remains accessible for inspection.
Re‑measure after machining to confirm final dimensions and surface finish.

7.3 Reading Tolerances (Typical IGCSE Values)

±0.1 mm – hand‑filed or manually marked parts.
±0.05 mm – calibrated calipers on machined metal.
±0.01 mm – CNC‑produced components or precision‑ground parts.

7.4 Testing & Inspection Methods

Fit Tests: Interference, clearance and transition fits using gauge blocks or slip gauges.
Surface‑finish Inspection: Visual check, surface‑roughness comparator, or portable profilometer (Ra values).
Mechanical Tests (optional for specialist option):
- Tensile Test: Determines ultimate tensile strength, yield strength and elongation.
- Bend Test: Checks ductility and resistance to cracking under a prescribed bend radius.
- Hardness Test: Brinell, Rockwell or Vickers methods to assess resistance to indentation.

8. Shaping Processes (Common‑Content)

Choose a process based on material, required accuracy, production volume and available equipment.

Process	Principle	Typical Materials	Key Equipment / Tooling	Advantages / Limitations
Bending (Press Brake)	Plastic deformation about a line (crease) using a punch‑die set.	Cold‑rolled steel, aluminium, mild‑steel sheets.	Press brake, V‑die, angle gauge.	Fast for simple angles; limited to sheet thickness < 10 mm; spring‑back may require over‑bending.
Casting (Sand / Permanent Mold)	Molten metal poured into a cavity and solidifies.	Aluminium, zinc, brass, low‑carbon steel.	Furnace, pattern, sand mould, ladle.	Complex shapes, low tooling cost; surface roughness high, dimensional accuracy moderate.
Die‑Casting	High‑pressure injection of molten metal into a steel die.	Aluminium, magnesium, zinc alloys.	Die‑casting machine, hot‑runner system.	Excellent surface finish, high production rate; high die cost, limited wall thickness.
Vacuum Forming	Thermoplastic sheet heated and drawn over a mould by vacuum.	PVC, PET, acrylic sheets.	Vacuum former, heating oven, mould.	Rapid prototyping of simple shapes; limited to thin sheets, lower dimensional accuracy.
Machining (Lathe / Milling / Drilling)	Material removed by a cutting tool driven against a workpiece.	Metals, plastics, composites, wood.	Lathe, milling machine, drill press, CNC centre.	High accuracy, good surface finish; slower for large volumes, tool wear must be managed.
Grinding (Surface / Cylindrical)	Abrasive removal of material to achieve very fine tolerances and surface finish.	Metals, hardened steels, some plastics.	Surface grinder, cylindrical grinder, abrasive wheels.	Produces Ra < 0.2 µm; limited material removal rate; requires coolant and dust extraction.
Sheet Metal Forming (Stamping, Deep‑drawing)	Plastic deformation of sheet using a die set under high pressure.	Steel, aluminium, copper sheets.	Stamping press, deep‑draw die, blank holder.	Very fast for high‑volume production; high tooling cost, limited to sheet‑metal geometries.

Tools and equipment: hand tools, power tools, machine tools