Scales of Production: One-Off, Batch, Mass, Continuous

This lesson covers the four scales of production used in manufacturing, as required by AQA GCSE D&T (8552), Section 3.2.7. Understanding scales of production is essential because the production volume determines the manufacturing methods, tooling, materials, and costs. This is a topic tested every year in the Paper 1 exam.

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The Four Scales of Production

The diagram below compares the four scales of production, showing how unit cost decreases and automation increases as volume rises:

graph LR
    A["**One-Off**\n1 product\nHighest unit cost\nHand tools"] --> B["**Batch**\n10s — 1000s\nModerate cost\nJigs & templates"]
    B --> C["**Mass**\n1000s — millions\nLow unit cost\nProduction lines"]
    C --> D["**Continuous**\n24/7 non-stop\nLowest unit cost\nFully automated"]

Scale	Also Known As	Quantity	Description
One-off	Jobbing, bespoke, prototype	1 (or very few)	A single, unique product made to a specific customer's requirements
Batch	—	Tens to thousands	A specific quantity of identical products made together, then the equipment is reconfigured for a different product
Mass	Repetitive, line production	Thousands to millions	Large quantities of identical products made continuously on production lines
Continuous	Process production	24/7, non-stop	Materials flow continuously through automated processes; the line runs non-stop

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One-Off (Jobbing) Production

One-off production creates a single, unique product. Each product is made individually and may be completely different from the next.

Feature	Detail
Quantity	1 (or a very small number)
Labour	Highly skilled craftspeople who can perform many different tasks
Equipment	General-purpose hand tools and machines (not specialised)
Flexibility	Very high — each product can be different
Unit cost	Very high (all costs borne by a single product)
Lead time	Long — each product is made from scratch
Quality	Can be very high (craftsperson's skill and attention to detail)

Examples of One-Off Production

Product	Why One-Off
Bespoke wedding dress	Custom-designed and fitted to one individual
Prototype of a new product	Testing a design before committing to mass production tooling
Commissioned piece of furniture	Made to the customer's exact specifications and room dimensions
Competition racing car	Unique design optimised for specific racing conditions
Architectural model	One-off representation of a specific building design

AQA Exam Tip: One-off production is associated with high cost per unit, high skill level, general-purpose tools, and maximum flexibility. If the exam gives you a scenario involving a custom or unique product, one-off is the correct scale.

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Batch Production

Batch production makes a specific quantity (a "batch") of identical products. After the batch is complete, the equipment is reconfigured (set up) for a different product or a new batch of the same product.

Feature	Detail
Quantity	Typically tens to thousands per batch
Labour	Semi-skilled workers performing repetitive tasks; some skilled workers for setup
Equipment	Combination of general-purpose and some specialised machines; jigs, fixtures, and templates ensure consistency
Flexibility	Moderate — can switch between products, but setup time is needed
Unit cost	Moderate (setup costs spread across the batch)
Lead time	Moderate — setup time plus production time
Quality	Consistent within a batch (jigs and templates ensure accuracy)

Examples of Batch Production

Product	Batch Size
Bakery producing different types of bread	200 loaves of white, then switch to 200 wholemeal, then 100 sourdough
Clothing manufacturer producing seasonal collections	500 of one design, then reconfigure machines for the next design
Furniture company producing a range of tables	50 dining tables, then switch to coffee tables
Printed circuit board (PCB) assembly	1,000 boards for one product, then change to another
School workshop producing identical projects	A class of 30 students making the same product

Jigs, Fixtures, and Templates