Riveted joints: the distance from the centre of a rivet hole to the nearest free edge of the plate is called what?

Introduction / Context:
Basic terminology of riveted joints is foundational in machine design and fabrication. Correctly identifying geometric parameters helps ensure adequate strength and prevents failures like tearing at the edges or shear-out.

Given Data / Assumptions:

• We consider a flat plate with rivet holes near a free edge.
• Standard nomenclature is used for riveted joint dimensions.

Concept / Approach:
Key distances include: pitch (centre-to-centre spacing of adjacent rivets along a row), back pitch or gauge (distance between parallel rows), and margin (also called edge distance), which is from the hole centre to the nearest free edge. Adequate margin prevents tearing along the edge under load.

Step-by-Step Solution:

Verification / Alternative check:
Texts in machine design consistently define margin as the edge distance, commonly specified as a multiple of plate thickness to avoid tearing failures.

Why Other Options Are Wrong:

• Pitch: centre-to-centre spacing of adjacent rivets, not to the edge.
• Back pitch (gauge): spacing between rows, not to the plate edge.
• Gauge: often synonymous with back pitch; not edge distance.
• None of these: incorrect because the correct term is listed.

Common Pitfalls:
Mixing up pitch and margin; using too small an edge distance that leads to tearing or poor hole quality after drilling.

Final Answer:
Margin (edge distance)