Definition
A rivet set is a hardened steel tool with a shaped end that matches the contour of a rivet head, used in the rivet gun to drive solid rivets without damaging the manufactured head. The opposite end is shaped to fit the rivet gun. Different rivet sets are used for different rivet head styles (universal, brazier, countersunk) and rivet diameters.
Plain English
A small steel attachment that fits into a rivet gun. It has a shaped tip that cups over the rivet head so the gun can hammer the rivet into place without flattening or marking the head.
Context Anchor
Seen in aircraft sheet-metal repair and solid rivet installation, especially when selecting tools before driving rivets in skin or structural parts.
Derivation
From rivet (a metal fastener) and set (a tool shaped to receive or form something). The set is the part that 'sets' the rivet head as the gun drives it.
Why Pilots Care
Using the wrong rivet set, or one in poor condition, can deform the rivet head, damage the surrounding skin, or produce a weak joint. Proper rivet set selection is part of producing an airworthy repair.
Intuition Check
Do not read set here as a collection of tools. In this term, a rivet set is one specific shaped tool used to drive a rivet.
Example Sentence 1
Before riveting the skin patch, the technician selected a rivet set that matched the universal head of the AN470 rivets.
Example Sentence 2
Using the correct rivet set ensures the rivet head forms properly without damaging the surrounding metal.