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← 4.1 Methods of joining sheet metal

Allowing metal for the seam

Metal Technology · Grade 10 · about 40 minutes

Why a seam consumes metal, how much to add at each edge, and what happens to an article marked out without an allowance.

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  • 6 sections of explanation, worked examples and diagrams
  • 1 practice task with hints and worked answers
  • A quiz that marks itself as you go
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Other lessons in this sub-strand

  1. Why sheet metal has to be joined
  2. What makes a joint a good one
  3. The butt joint
  4. The lap joint
  5. The grooved seam
  6. Other seams and where each is used
  7. Allowing metal for the seam
  8. How a rivet holds
  9. Rivet types and sizes
  10. Setting a rivet
  11. Rivet spacing and edge distance
  12. Pop rivets
  13. Bolts, nuts and screws in sheet
  14. Self-tapping and machine screws
  15. How soft soldering works
  16. Flux and preparing the surfaces
  17. Making a soldered joint
  18. Choosing a joining method
  19. Safety in sheet-metal joining
  20. A joining task: making a tray