A school receptionist needs a notice board outside the main entrance where parents can read messages about events and term dates. The current notices are pi...

(a) Four functional points [4 marks]

1. Transparent front cover — Notices must be readable through the cover without opening it. A clear, weather-resistant panel (acrylic or polycarbonate) protects printed paper from rain, wind, and direct sunlight while keeping the text and images visible to parents and visitors passing by. [1]
2. Easy notice replacement — School notices change frequently (weekly events, term dates, emergency information). The cover must open to allow staff to pin, staple, or clip new notices onto the backing surface and remove outdated ones quickly. The backing material must accept drawing pins or staples. [1]
3. Capacity for multiple A4 notices — The usable display area must be large enough to show at least six A4 sheets (210 mm x 297 mm) arranged side by side or in a grid. This requires a minimum internal display area of approximately 600 mm x 500 mm. [1]
4. Locking mechanism — An outdoor notice board accessible to anyone could have notices removed or replaced by unauthorised people. A simple lock (cam lock, hasp and padlock, or key-operated catch) restricts access to authorised staff while being quick to open with a key. [1]

(b) Two hinge arrangements [4 marks]

Arrangement 1 — Top-hinged cover with gas strut stay: The transparent cover is hinged along its top edge, swinging upward to open. A gas strut (similar to those on car boot lids) holds the cover open at approximately 90 degrees while staff change notices, preventing it from falling shut. The top-hinge design means rainwater runs off the closed cover naturally, as the hinge is at the highest point. [2]

Arrangement 2 — Side-hinged cover (door style) with magnetic catch: The cover is hinged on one side using two butt hinges, opening like a door. A magnetic catch on the opposite side holds the cover closed when the lock is not engaged. This arrangement provides full access to the notice area from one side, making it easy to reach all corners. A rubber seal runs around the frame to prevent water ingress when closed. [2]

(c) Three design ideas [12 marks]

Idea 1 — Framed box with top-hinged acrylic cover and rubber seal: A rectangular timber or aluminium frame (700 mm x 550 mm x 50 mm deep) encloses a cork-backed display area. A 3 mm acrylic sheet is hinged along the top edge and sealed around the remaining three edges with EPDM rubber strip when closed. A cam lock at the bottom secures the cover. A gas strut holds the cover open for changing notices. The frame is powder-coated for weather resistance and mounted on the wall with concealed brackets. [4]

Idea 2 — Curved-front unit with sliding panel: A wall-mounted case with a curved clear polycarbonate front panel that slides sideways along top and bottom tracks to open. The curved profile sheds rainwater effectively and gives a modern appearance. The sliding mechanism avoids the need for space in front for a hinged door to swing open. The tracks must be precisely aligned to prevent jamming, which adds manufacturing complexity. [4]

Idea 3 — Double-door cabinet with central meeting edge: Two glazed panels, hinged on opposite sides, meet in the centre with a magnetic catch and overlapping lip. A key lock at the meeting edge secures both doors. This design provides wide access to the full notice area by opening both doors simultaneously. A felt or rubber seal runs around the frame perimeter. The double-door arrangement requires two sets of hinges and precise alignment at the central meeting point. [4]

(d) Evaluation and justification [8 marks]

Idea 1 (Top-hinged box) — Strengths: the top hinge positions the seal at the sides and bottom, where driving rain is more likely to enter than at the top; the gas strut holds the cover open hands-free; simple rectangular construction. Weaknesses: the cover, when open, projects above the board and may catch wind.

Idea 2 (Sliding panel) — Strengths: no door swing; curved profile sheds rain well. Weaknesses: sliding tracks are difficult to manufacture accurately and can jam or accumulate debris; the curved polycarbonate is harder to source than flat sheet.

Idea 3 (Double doors) — Strengths: wide access. Weaknesses: the central meeting edge is the weakest point for water ingress; two sets of hinges add cost and weight; alignment of the overlapping lip is critical.

Chosen idea: Idea 1. The top-hinged framed box provides the best combination of weather sealing (the hinge at the top ensures rain runs off the closed surface naturally), ease of access (the gas strut holds the cover open hands-free), and simplicity of construction (a rectangular frame with one set of hinges). The cam lock at the bottom is easy to operate and secure. [8]

(e) Full solution — construction details [12 marks]

The solution is drawn in isometric projection with a cross-section through the seal and a detail of the cover in its open position.

• Frame: Powder-coated aluminium extrusion (25 mm x 25 mm L-profile), mitred and joined at the corners with stainless steel corner brackets and M4 machine screws. External dimensions: 700 mm wide x 550 mm tall x 50 mm deep.
• Backing: 12 mm MDF (680 mm x 530 mm) with a 6 mm cork sheet bonded to the front face using contact adhesive. The cork accepts drawing pins and staples. The MDF-cork sandwich is screwed into the aluminium frame from behind.
• Front cover: 3 mm clear acrylic sheet (680 mm x 530 mm), hinged to the top of the frame with a stainless steel piano hinge (680 mm long). A gas strut (150 N rating) is attached between the frame side and the cover to hold it open at 90 degrees.
• Seal: EPDM rubber strip (5 mm x 10 mm, self-adhesive) runs continuously around the three non-hinged edges of the frame. When the cover closes, it compresses the rubber strip to form a watertight seal.
• Lock: A cam lock (19 mm barrel) is fitted through the bottom rail of the frame. The cam engages with a keep plate on the acrylic cover edge.
• Wall mounting: Two heavy-duty mirror plates (one top, one bottom) screwed to the rear of the frame, fixing into wall plugs with 50 mm coach screws. The board is positioned at 1400 mm from the ground (adult reading height).

(f) Materials [4 marks]

1. Powder-coated aluminium extrusion for the frame. Aluminium is lightweight (reducing the load on wall fixings), completely corrosion-proof in an outdoor environment, and the powder coating provides a durable, coloured finish (school colours can be matched) that resists UV degradation and chipping. Aluminium extrusion can be cut cleanly with a hacksaw and filed to accurate mitres. [2]
2. EPDM rubber strip for the seal. EPDM (ethylene propylene diene monomer) is a synthetic rubber specifically formulated for outdoor weather sealing. It is resistant to UV radiation, ozone, rain, and temperature extremes (-40 to +120 degrees Celsius). It retains its flexibility and compressive recovery over years of repeated opening and closing, maintaining a watertight seal throughout the product's life. [2]

(g) Manufacturing the frame [6 marks]

1. Mark out: Measure and mark the four frame lengths on aluminium extrusion using a scriber and steel rule. Mark 45-degree mitre angles at each end using a combination square. [1]
2. Cut mitres: Clamp the extrusion securely in an engineer's vice and cut each mitre using a hacksaw with a fine-toothed (32 TPI) blade, keeping to the waste side of the scribed line. [1]
3. File smooth: File each mitre face smooth and flat using a flat file, checking the angle frequently with a combination square set to 45 degrees. A smooth, accurate mitre ensures tight corner joints with no gaps. [1]
4. Drill fixing holes: Drill and countersink fixing holes at each corner position for the joining screws, using a pillar drill with a 4 mm twist bit followed by a countersink bit. [1]
5. Assemble frame: Assemble the four lengths into a rectangular frame using stainless steel corner brackets and M4 machine screws. Check squareness with a try square at each corner before tightening fully. [1]
6. Finish: Clean the assembled frame with fine emery cloth to remove filing marks. If the extrusion was not pre-coated, apply a coat of metal primer followed by two coats of exterior spray paint, allowing drying between coats. [1]