Isometric rendered drawing of your final design

Do Now · 5 min

From Term 1 L13 — answer in your folio:

1. Isometric horizontal lines are drawn at ___ degrees.
2. What are the 3 steps of the Y method?

I Do · ~10 min Teacher demonstration

Teacher models an isometric rendered bridge drawing on the board — 7 steps:

1. Y method — vertical line, then two 30° lines outward.
2. Build a bounding box that fits the whole bridge (450 × 200 × 150 mm real → scale to paper).
3. Mark the 4 corners of the deck. Connect.
4. Sketch in truss members on the visible side.
5. Light construction lines only at this stage.
6. Outline the final edges with darker pencil.
7. Render with 3 tones — highlight top (light), mid-tone side facing us, shadow under-deck.

We Do · ~15 min Guided practice

Together we render a simple isometric box using the 3-tone technique:

• Top face — lightest, barely touched
• Left side — medium, even strokes
• Right side — darkest, firm pressure, even direction

You Do · ~35 min Independent pair work

Your isometric rendered drawing (30 min).

1. Use isometric dot paper (take one from the pile).
2. Use Y method to start the bounding box.
3. Build up your truss on the visible side.
4. Show the deck and the far-side truss as parallel lines.
5. Render with 3 tones (HB or 2B pencil).
6. Label members in technical lettering: TOP CHORD, BOTTOM CHORD, VERTICAL, DIAGONAL, DECK.
7. Add a title: bridge name + scale (approx 1:5 on isometric paper).

Differentiation

Exit Ticket · 5 min

1. Which face of your bridge is the LIGHTEST (highlight)?
2. What is the 30/120 rule in one sentence?

📚 Resources for this lesson

• Term 1 L13 recap — isometric drawing
• Isometric dot paper (printable)
• Example isometric bridge (on hub)

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