This is arguably the most critical digit because it defines strength and corrosion resistance. In the standard format, the first digit after the dash represents the .
Solid shank rivets are permanent fasteners consisting of a shank and a head, commonly used for high structural strength in aircraft skins and frames. : nas523 rivet code pdf
NAS523-6-4-6 = A solid, universal head rivet made of Aluminum 5056, 1/8" in diameter, 3/8" long. This is arguably the most critical digit because
The code tells you the nominal length, but the PDF tells you the acceptable tolerance (+/- .010 inches). When installing a rivet for a hydraulic reservoir or a wing spar, that .010 matters. : NAS523-6-4-6 = A solid, universal head rivet
NAS523 Rivet Identification Guide | PDF | Rivet | Sheet Metal. NAS523 Solid Rivet Specifications | PDF - Scribd
Let’s break down a real-world example:
Boeing and Airbus do not give away NAS523, but their Standard Overhaul Practices manuals (e.g., Boeing D6 series) contain extensive excerpts from NAS523. If you have access to MyBoeingFleet or Airbus World, search "Rivet Identification."