First Article Inspection for Fasteners: FAI and PPAP Without the Theater
First Article Inspection is the contract moment between design intent and production reality. Done well, it prevents a year of quality disputes; done as theater, it is a PDF nobody reads.
What a useful FAI contains
Measurement against the drawing, balloon-numbered to every callout, with actual values — pass/fail summaries without numbers prove nothing. For fasteners add the functional tests the drawing implies: thread gaging (Go/No-Go), torque-preload sample data, hardness per class, and coating thickness with salt-spray reference lots.
PPAP levels in automotive supply
- Level 1: part submission warrant only — for trivial changes.
- Level 3: full package — dimensional results, material and performance test results, process capability (Cpk on key characteristics), control plan. The norm for new fastener part numbers.
- Level 5 with on-site review: safety-critical hardware.
What distinguishes a good supplier
The FAI should flag marginal characteristics honestly — a Cpk of 1.12 on head height is information, not failure. Topprecision issues FAI/PPAP packages with raw data attached, and walks customer SQEs through any characteristic below 1.33 before the warrant is signed.
