[RBR]

Guys,

RV-8 pre-punched flaps.

The plans call for the upper and lower skins to be riveted together using flush rivets. During mock up and before match drilling, I was very happy with the fit. Having now dimpled both skins, the top skin does not nest perfectly over the lower skin dimples. This is along the spanwise row of rivets on the lower surface, just forward of the 'rear spar'. Despite putting an edge roll into the upper skin (Cleveland tool), I can get my finger nail under the skin. The parts are currently being held by just the clecos.

Already done are:

1. Edge roll.
2. TE squeezed so the skins sit flush.
3. All cleco removed apart from the join in question.

What I hope will happen is for the skins to nest correctly when tapped by the rivet gun.

Before I commit to riveting the parts together is there something else I should look for?

Many thanks,

RBR

 

[mcencula]

Should be fine...

...but if you want them to nest together really well, you might consider using a set of the Cleaveland tank dies for the underneath skin. These dimples will be ~.007 inch deeper and allow the dimples in the top skin to nest somewhat better. I've used both methods (with and without tank dies) and the difference is noticeable, yet slight.

If you want to see how they will end up, try dimpling a couple pieces of scrap and see if the gap closes up the way you want. If that's not going to make you happy, then go ahead and spring for the tank dies.