Year 7 Technology · 2026
Week 6 · Lesson 12

Top chord + vertical members

Week 6 · 75 minutes · Year 7 Technology (Mandatory) · Bridge It

TE4-3DP

🎯 Learning intentions

  • I can build a top chord parallel to my base chord.
  • I can position and glue vertical members accurately.
  • I can use a template jig to keep my frame square.

✅ Success criteria

  • My folio has a photo of my in-progress truss with top chord and verticals in place.
  • My verticals are straight (90° to chords) — checked with a ruler or set square.
  • All joints are clean (no big glue blobs visible).

Do Now · 5 min

Quality check on your Lesson 11 base chord. Is it:

  1. Straight when viewed from above? (Sight along it like aiming a pencil)
  2. Flat when viewed from the side?
  3. All joints dry and firm?

Write in your folio: "My base chord ___ (passed / passed with notes). Notes: ___."

I Do · ~10 min Teacher demonstration

Teacher models adding verticals to the chord.

  1. Lay base chord flat on work surface.
  2. Mark vertical positions along the chord using pencil + ruler (every 60 mm on the exemplar).
  3. Hold vertical perpendicular using a set square or a pre-cut template jig.
  4. Apply small PVA drop at joint.
  5. Tape vertical to hold while drying.
  6. Repeat for each vertical.
  7. Then — measure the top chord length, cut, dry-fit, glue on top of all verticals.
Key rule: 90° verticals are non-negotiable. A tilted vertical multiplies errors up the whole truss.

We Do · ~15 min Guided practice

Class practice: everyone dry-fits (no glue yet) 2 verticals onto their chord. Teacher walks and checks angles. Once approved, you glue.

You Do · ~35 min Independent pair work

Complete top chord + verticals for truss #1 (35 min).

  1. Mark all vertical positions along base chord.
  2. Cut verticals to correct length (check your drawing from L08).
  3. Glue verticals one by one using template jig.
  4. Once all verticals are firmly set, add the top chord on top.
  5. Check squareness — every 4 corners of every rectangle should be 90°.
  6. Take photo 2 for journal. Caption: "L12 – Top chord and verticals done on truss 1."
  7. Clean up: cap glue, return tools, newspaper into recycling.

Differentiation

🪜Support

Pre-cut verticals (all 60 mm). Pre-marked chord. Pair works with Ms Gao's jig.

🎯Core

Cut, measure, and glue with partner.

🚀Extension

Use double-layer verticals (lamination) at the most loaded positions (middle of bridge).

Exit Ticket · 5 min

  1. What angle should every vertical meet the chord?
  2. Which Term 1 lesson does this 90° rule remind you of?
  3. Photo taken for journal? (yes/no)

📚 Resources for this lesson

Before you leave Quick check-in

🚩 Stuck or confused?

Click this button to flag to Ms Gao that you need a 1-to-1 next lesson. Your message is copied — paste it into a Google Classroom private comment.

📄 Export journal so far

Save your journal as a .txt file to upload to Google Classroom for Ms Gao's Friday review.

📓 Open journal + export