Rivet Mil-Spec, or is it?!?!

I riveted my left leading edge over the past couple of days. I ended up drilling out about 10 rivets overall that I wasn't happy with. I also used 4 oops rivets as some of the holes got a little big.

So this led me to an interesting observation. I was looking at the mil-spec for a 3/32 rivet. The max hole tolerance is .103. I measured my untouched dimpled holes and they were literally already at the max tolerance. I reamed them with a #40 reamer and dimpled with a standard cleaveland dimple die on a c-frame. So since they're already starting at max tolerance, anytime I drill out a 3/32 AN426 rivet, the hole is going to be out of spec.

What I typically do is just use a longer rivet, plump it a bit with a squeezer, and then set it with a bigger shop head. I'm wondering if I should start match drilling with a #41 bit and see if that helps.

Anywho, I thought it was an interesting observation.

#41

I always wondered about that too, but there's a lot of Vans flying so I quit worrying about it.
I often ho 1/2 size up for that reason. I prefer a bit more shop head.
You might find after deburring a Vans hole, it's just about perfect for a dimple. #41 is pretty close. Too small and the hole can crack so test first.

I always appreciate your insight Larry. Your builder blog is one of my go to sites when I'm scratching my head...or banging it on the wall trying to figure something out. Such a learning curve....