Shaping and Forming

This lesson covers the key shaping and forming processes across all material categories, as required by AQA GCSE D&T (8552), Section 3.2.5. Shaping and forming convert raw materials into the desired product shape. Understanding these processes — how they work, what they are used for, and their advantages and limitations — is essential for both the exam and the NEA.

---

Bending

Bending involves applying a force to a material to change its shape from flat or straight to curved or angled.

Bending Metals

Method	Process	Material	Application
Cold bending (using a vice and hammer)	Metal is clamped in a vice and hammered over a former	Mild steel, aluminium, copper	Simple brackets, right-angle bends in bar and sheet
Using a folding bar (sheet metal)	Sheet metal is clamped between two bars and bent by hand	Thin sheet metal (up to ~1.6 mm)	Sheet metal boxes, enclosures, trays
Press brake	A machine presses sheet metal into a V or U die	Steel, aluminium sheet	Precise bends in sheet metal production; batch and mass production
Tube bender / pipe bender	A mechanical device bends tube around a former	Copper, steel tube	Plumbing pipes, bicycle frames, roll cages

Bending Polymers

Method	Process	Material	Application
Line bending (strip heater)	A narrow heating element softens thermoplastic along a line; the sheet is then bent over a former	Acrylic, HIPS, polypropylene	Phone stands, menu holders, simple boxes, display stands
Hot air gun bending	A hot air gun softens a wider area of thermoplastic for free-form bending	Acrylic tube, polypropylene sheet	Curved shapes where a straight bend is not required

Bending Timber

Method	Process	Material	Application
Steam bending	Timber is steamed in a steam box to make it pliable, then bent around a former and clamped until dry	Ash, oak, beech (hardwoods with long grain)	Chair backs, boat ribs, walking sticks (e.g. Thonet bentwood chairs)
Laminate bending (kerf bending not needed if laminating)	Thin veneers are glued together and clamped over a curved former	Any timber veneer	Curved furniture (e.g. Eames lounge chair shell), architectural elements

AQA Exam Tip: Line bending is one of the most commonly examined forming processes. Know the steps: (1) Mark the bend line, (2) Place the thermoplastic sheet over the strip heater, (3) Heat evenly, turning regularly, until the sheet becomes soft and floppy along the line, (4) Bend over a former to the required angle, (5) Hold until cool. Also know that ONLY thermoplastics can be line-bent (thermosetting polymers cannot be reheated).

---

Vacuum Forming

Vacuum forming is a process for shaping thermoplastic sheet material over a mould using heat and vacuum pressure.

The Process

1. A mould (pattern) is placed on the platform of the vacuum forming machine.
2. A thermoplastic sheet (e.g. HIPS, ABS, PETG) is clamped above the mould.
3. The sheet is heated until it becomes soft and pliable (drapes slightly).
4. The platform is raised so the mould pushes into the softened sheet.
5. A vacuum pump removes the air between the sheet and the mould, pulling the softened plastic tightly around the mould.
6. The plastic is allowed to cool and harden in its new shape.
7. The formed shape is removed from the mould and trimmed to the final size.

Key Points

Feature	Detail
Suitable materials	Thermoplastics only: HIPS, ABS, PETG, acrylic, PVC, polypropylene
Mould requirements	Must have draft angles (slightly tapered sides) so the formed plastic can be removed; no undercuts
Typical products	Packaging trays, chocolate box inserts, yoghurt pots, seed trays, bath panels, signage
Production volume	Suitable for one-off, batch, and mass production
Advantages	Relatively cheap tooling, fast process, good for large surface areas
Limitations	Limited to relatively simple shapes; thin areas where plastic stretches over sharp corners; only one surface has mould detail

---

Injection Moulding

Injection moulding is the most widely used manufacturing process for producing high-volume polymer products.

The Process