Studio Matrx Monthly · Volume 1 · Issue 2 · July 2026
Amogh N P
✦ In loving memory of Amogh N P — Architect · Designer · Visionary ✦
A model-maker's desk from above — a metal scale rule, a set square and a pencil laid over flat cut card templates of walls and a floor plan on a green cutting mat, warm daylight, no people, no legible text.
Unit IIModel Making

Scale & Templates

Reducing reality — and reading a drawing into flat pieces.

≈ 50 min + scale exercisesByAmogh N P· Architect & interior designer

Scale is the single most important concept in the course — the ratio between a model dimension and the real one; 1:20 means the model is one-twentieth of full size. Learn to convert real to model dimensions, to choose a scale for the purpose (detail must be earned by scale), and to read plans and sections and unfold them into flat cutting templates — mastering the two precision issues that separate a good model from a sloppy one: grain, and the board-thickness problem.

Learning objectives

By the end of this lesson, you will be able to — mapped to the course outcomes for Model Making:

1
CO2 · Apply

Convert real dimensions to model dimensions at any scale.

2
CO2 · Analyse

Choose a model scale for the purpose, matching detail to scale.

3
CO2 · Apply

Read plans, sections and elevations and unfold them into cutting templates.

4
CO2 · Understand

Account for grain direction and material thickness at joints.

The one skill to own

Scale & choosing it

Converting real to model dimensions, the scale rule, and choosing a scale for the purpose with detail earned by scale.[1, 4]

Scale: the one skill to own real: 1 m (1000 mm) ÷ scale factor 1:20 → 50 mm 1:50 → 20 mm 1:100 → 10 mm Beware the trap: 1:20 is a LARGER scale than 1:100 — bigger model, more detail. 1:100 reduces MORE. real dimension ÷ scale factor = model dimension
DiagramModel scale — real dimension divided by the scale factor gives the model dimension; 1 metre becomes 50mm at 1:20
Choose a scale for the purpose 1:100 massing, whole plan no furniture detail 1:20 — the interior room furniture, fittings, materials 1:5 — a detail (a stair) Detail must be EARNED by scale A 1:100 model showing a drawer pull is dishonest — the pull would be 0.15 mm. A 1:20 sofa reduced to a plain block is under-committed. Match detail to scale.
DiagramChoosing a scale for the purpose — massing at 1:100, a whole interior room at 1:20, a detail at 1:5; detail must be earned by scale

The one skill to own

A model scale states the ratio between a model and the real dimension: 1:20 means one unit on the model equals twenty in reality — the model is 1/20th of full size. The conversion: REAL DIMENSION ÷ SCALE FACTOR = MODEL DIMENSION (in consistent units, then to mm for cutting). So 1 m becomes 50 mm at 1:20, 20 mm at 1:50, 10 mm at 1:100. Beware the beginner trap: 1:20 is a LARGER scale (bigger model, more detail) than 1:100. The scale RULE carries several ratios on its faces so you read model dimensions straight off a drawing — but learn the arithmetic too. Try the scale converter below.[1, 4]

Real → model

Try it — the scale converter

Enter a real dimension (or pick a common object) and a scale to read the model dimension in millimetres.

Scale converter · real → model dimension

Model dimension

150 mm

3000 mm ÷ 20 = 150 mm

Remember: 1:20 is a LARGER scale than 1:100 (bigger model, more detail) — and account for board thickness at every joint.

Unfolding, grain, thickness

Templates & precision

Reading drawings into flat cutting templates (nets), grain direction, and accounting for material thickness at joints.[1, 2, 3]

Unfold the drawing into a flat NET □ floor (plan) wall wall opening fold up … then folded into the box Cut openings IN THE FLAT — far more accurate than cutting an assembled box.
DiagramUnfolding a room's plan, walls and ceiling into a flat cutting template or net, then folding it back into the box
The board-thickness problem Exact lengths, butted → oversize the overlap adds one board-thickness per joint Mitre 45° → clean corner both edges cut to 45° hide the thickness The thickness also represents a real dimension: 5 mm foamboard = 100 mm wall at 1:20 (fine) · 250 mm at 1:50 (thick) · 500 mm at 1:100 (absurd). Choose a sensible thickness for the scale.
DiagramThe board-thickness problem — butting walls at exact length makes the room oversize; compensate or mitre the corners

Card has grain too

Sheet materials have a directional GRAIN — the fibre direction in card and mount board, the wood grain in balsa and basswood. Material bends easily ALONG the grain and resists bending across it, and cuts cleaner WITH the grain. For clean straight cuts and parts that must stay flat, orient long edges thoughtfully to the grain; for a curved or rolled piece, roll ACROSS the grain so it curves willingly. Ignoring grain gives ragged cuts and warped, bowing walls.[1]

Myth vs reality

At a glance

AspectOne sideThe other
1:20 vs 1:100Myth: 1:20 is smaller than 1:100Reality: 1:20 is larger — bigger model, more detail
Detail at any scaleMyth: add as much as you likeReality: below a size a feature is unbuildable
Wall lengthsMyth: cut every wall to exact lengthReality: compensate for board thickness at joints
Material thicknessMyth: it doesn't matterReality: it offsets joints AND represents a real thickness
GrainMyth: only a woodwork concernReality: card warps and cuts ragged if ignored
Vocabulary

Key terms

Scale

The ratio of a model dimension to the real one; 1:20 means the model is one-twentieth of full size.

Scale conversion

Real dimension ÷ scale factor = model dimension (1 m → 50 mm at 1:20).

Scale rule

A ruler carrying several ratios on its faces, to read model dimensions straight off a drawing.

Net / template

The flattened pattern of all a model's faces, laid out flat for cutting before assembly.

Grain direction

The fibre direction in card and wood — it bends and cuts more willingly one way.

Board-thickness problem

Butting walls at exact length makes a room oversize; compensate for thickness at each joint.

Apply it

Making task

Take a real room (say 3.6 × 4.2 m, 3.0 m ceiling, with a 0.9 × 2.1 m door) and, at 1:20, build a full conversion sheet — the model length of every wall, the ceiling height, and the door opening, in millimetres. Then draw the flat net (floor plus four walls) as cutting templates with the door opening marked, and note how much you would shorten or mitre each corner to solve the board-thickness problem for 5 mm foamboard.

Check your understanding

Self-assessment

1. At 1:20, a real 3.0 m ceiling height becomes a model height of —

2. Which scale is LARGER — 1:20 or 1:100?

3. The 'board-thickness problem' means that if you cut every wall to its exact scaled length —

In a nutshell

Recap

Scale is the ratio of model to real; convert with real ÷ scale factor = model (1 m → 50 mm at 1:20) — and 1:20 is larger than 1:100.
Choose a scale for the purpose: massing at 1:100, a whole interior room at 1:20 — and detail must be earned by scale.
Read plans, sections and elevations, then unfold them into flat cutting templates (nets); cut openings in the flat before assembly.
Mind grain direction — card and wood bend and cut more willingly one way, and warp if it is ignored.
Account for material thickness at every joint (the board-thickness problem), and choose a thickness that represents a sensible real dimension.
The evidence

References & further reading

  1. [1]Nick Dunn, Architectural Modelmaking, 2nd ed., Laurence King, 2014 (scale, materials, drawing-to-model translation).
  2. [2]Megan Werner, Model Making, Princeton Architectural Press, 2011 (developing parts from drawings).
  3. [3]Criss B. Mills, Designing with Models, 3rd ed., Wiley, 2011 (templates and parts from process drawings).
  4. [4]Maureen Mitton & Courtney Nystuen, Residential Interior Design: A Guide to Planning Spaces, 3rd ed., Wiley, 2016 (human-dimension data for accurate scaling).

Further reading

  • Nick Dunn — Architectural Modelmaking.
  • Criss B. Mills — Designing with Models.
  • Mitton & Nystuen — Residential Interior Design.

Sources gathered and fact-checked June 2026. Published values vary by source, sample and method — treat as indicative and confirm against the cited standard before structural use.

A

The author

Amogh N P

Architect, interior designer, and creative polymath. Studio Matrx began in his notebooks — his vision of design made honest, useful, and open to everyone. Its Academy is written and taught in his memory, and free, forever.

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