Issue 01 · The Sales Pitch · Brochures & Manuals
The Exploded Diagram
The workshop manual invented a way of drawing that has since been borrowed by furniture makers, software documentation and everyone who has ever assembled a flat pack.
What the drawing is doing
An exploded view separates every component of an assembly along a common axis, holding each part in the position it occupies relative to its neighbours but with air between them. You can see the order of assembly and the orientation of every piece in a single image.
It is a genuinely clever solution to a hard problem, which is how to show three-dimensional sequence on a flat page without a series of steps. And it is almost entirely unimprovable: modern CAD renderings of the same idea are prettier and no clearer.
The draughtsman as author
These drawings were made by hand, on a board, by people who understood the assembly well enough to decide what could be simplified and what could not. That editorial judgement is why the good ones work and the bad ones do not.
A poor exploded diagram shows everything at equal weight and becomes unreadable. A good one suppresses fasteners into a single representative bolt, breaks the axis where a sub-assembly deserves its own cluster, and uses line weight to separate foreground from background.
None of that is drawing skill. It is editing, done with a pen, and it is why the best workshop manual illustrations are credited in some publishers' colophons and treated as authored work.
Why the genre peaked and stopped
Hand-drawn technical illustration was expensive and slow, and it survived as long as it did because there was no alternative. Photography cannot do it, because a photograph of a disassembled gearbox is a photograph of a mess.
Once CAD models existed the drawings could be generated from the design data, which is faster, more accurate and less legible. A generated explosion has no editorial hand in it, so nothing is suppressed and everything is drawn at the same weight.
The result is that a manual from 1972 is often genuinely easier to follow than the equivalent for a car built in 2012, which is not a nostalgic claim. It is a consequence of removing the illustrator.
Where the style went
The visual language escaped the workshop entirely. Flat-pack furniture instructions, model kit sheets, appliance manuals and a great deal of software onboarding all use the same grammar of separated components on an implied axis.
It has become one of those design conventions so successful that it reads as neutral rather than as a style, which is the highest compliment available to an information designer. the Design Museum has run exhibitions on exactly this kind of invisible design work.
Duncan Ashby, February 2026
Next piece: Why the Car Is Always on a Hill