Wing skin gaps

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Joe Parish
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Wing skin gaps

Post by Joe Parish »

Looking for advice on my wing skin gaps. I have a slight twist in my right tank. It is about 1/32. I have virtually no gap between my fuel tank and the top and bottom skins. Moving over to the leading edge I have about 1/32 gap between the LE and bottom skin and between the LE and the top skin is @ .020 and tapers to @ .030 (1/32) at the outboard edge of the skins. Before I clecoed the bottom skins on I ran a string across the lower holes in the spar and it was slightly high in the middle with nothing underneath to support it. I could not get it to drop anymore. That was with top skins, tank and leading edge on. I put the bottom skins on and have removed the leading edge a couple times. I now have the gaps mentioned previously with the gap between the tank and leading edge about 1/32 from the spar to about just over to top to the back side where it closes completely with no gap. Hence the twist. I have no intentions of pulling the tank apart for 1/32 but am looking for options.
My understanding is that the gaps could open up after riveting, wondering if that is what others have seen.
Should I remove a little material from the leading edge skin on the back side where it is tight against the tank skin?
Do the gaps I listed at the top of this post seem ok?
I did recheck for twist in the wing and it seems to be more than the last time I checked but within the 3/32 allowable according to the instructions.
I hope this makes sense? My gut says build on. I wanted to check the gaps before I riveted the leading edge together. Any thoughts?
Joe
N525XC reserved
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captain_john
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Post by captain_john »

Joe, RIVET IT!!!

They will close up after riveting!

Mine did and so did everyone that I know.

What have others found??? Anyone discover the contrary?

8) CJ
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TomNativeNewYorker
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Post by TomNativeNewYorker »

over the years I have used a structural adhesive Hysol EA 9394 for shimming in areas that are not consistent enough in thickness to use ordinary metal shim stock. we refer to it as 'liquid shim'. it is grey in color and gets hard as a rock after cured and easy to drill or grind to shape or for clean up after curing. If you are familiar with JB weld, you could say it is a distant cousing to this stuff, but I am in no way advocating use of JB weld in aeronautical applications. This EA9394 we use has been authorized by engineers for past and present military aircraft I have worked on.



http://www.henkelna.com/cps/rde/xchg/he ... 0000000ISD

Spike
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Post by Spike »

captain_john wrote:Joe, RIVET IT!!!

They will close up after riveting!

Mine did and so did everyone that I know.

What have others found??? Anyone discover the contrary?

8) CJ

Im with John, rivet it.

Spike
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Joe Parish
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Location: Sioux Falls SD

Post by Joe Parish »

Ok Thanks guys. My biggest concern was the lack of a gap on the leading edge and tank skins.
Joe
N525XC reserved
Empennage done
wings done
Fuse in progress
RV-9A

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