Had an inspector tear apart my rivet work on a Cessna 172 last month and it still bugs me

So this FAA mechanic did a spot check on a rudder I was working on and said I was leaving too much gap between the rivets. He counted 5 that were like 1/32 off from the spec. I argued that it still holds fine but he said it invites corrosion later on. Now I'm double checking every single row but part of me thinks it's overkill on older airframes that already have dents everywhere. What do you guys think - is that level of perfection really worth the extra time or was he just being picky?

2 comments

2 Comments

angelas7819d ago

You said "it still holds fine" but that's the thing with corrosion, right? It's not gonna show up tomorrow, it's gonna show up in five years when you're not the one looking at it anymore. How long have you been working on Cessnas? Because that 1/32 gap might be okay on a 40 year old airframe that's already got some pitting, but on a cleaner plane that moisture can sit and creep under the edge of the head. Was the inspector known for being a stickler or did he have a reputation for letting things slide when it actually mattered?

elizabeth_ramirez18d ago

Hear me out though. I've been doing sheet metal on Cessnas for about 12 years now. Not a ton but enough. That 1/32 gap with a solid rivet job from the factory is actually tighter than a lot of field repairs I've seen pass inspection. The corrosion thing you're worried about is real, but it depends on the gap shape. If it's a straight line gap with no burrs, moisture doesn't wick in like you think. It pools on the surface, not under the head. A flush rivet with a tiny gap actually lets water run off faster than a tight one that traps debris. I get your point about a stickler inspector, but in my experience the guys who fail you for that are usually compensating for other stuff they missed. Five years out, the plane will be fine if the sealant was applied right under the head.